ORTHOPEDIC MCQS ONLINE QUESTION BANK H1D

Which of the following is a significant risk factor for a motor nerve palsy following a primary hip replacement:

 

1) Age <50 years

3) Prior hip surgery

2) Female sex

5) Developmental dysplasia

4) Body mass index >30

 

Farrell and colleagues from the Mayo Clinic recently reported a 0.17% rate of motor nerve palsy following 27,000 primary hip arthroplasties.

The important points to remember are:

 

Nerve distribution: peroneal 64%; sciatic 30%; femoral 6%

 

 

Complete nerve palsy 62%; incomplete 38% 87% of patients had a sensory deficit

 

 

Presumptive etiology in 26/47 (hematoma, traction, limb lengthening, laceration) Recovery

 

Complete palsy: full 36%; partial 39%; none 25%

 

Incomplete palsy: full 39%; partial 17%; none 44%

 

 

Leg lengthening is a significant risk factor (conditional logistic regression) Odds ratio 1:1

 

 

Average lengthening 1.7 cm (range: 1.1 cm to 4.4 cm) Significant factors (univariate logistic regression)

 

 

 

 

Developmental dysplasia Post-traumatic arthritis Posterior approach Uncemented arthroplasty

 

 

46% required a walking aid at follow-up Correct Answer: Developmental dysplasia

 

892. (3280) Q2-4124:

 

 

 

slide 1 slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. The most likely diagnosis is:

 

1) Enchondromatosis

3) Multiple hereditary exostoses

2) Eosinophilic granuloma

5) Spondyloepiphyseal dysplasia

4) Fibrous dysplasia

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: Multiple hereditary exostoses

Which of the following statements is true in patients who have an immediate motor nerve palsy following a total hip arthroplasty:

 

1) Sciatic nerve palsy is more common than peroneal nerve palsy.

3) The majority of patients with an incomplete palsy will have a full recovery.

2) The majority of patients with a complete motor palsy will have a full recovery.

5) Prior hip surgery is not a significant risk factor

4) A body mass index of 30 or higher is a significant risk factor.

 

Farrell and colleagues from the Mayo Clinic recently reported a 0.17% rate of motor nerve palsy following 27,000 primary hip arthroplasties.

The important points to remember are:

 

Nerve distribution: peroneal, 64%; sciatic, 30%; femoral, 6%

 

 

Complete nerve palsy, 62%; incomplete, 38% 87% had a sensory deficit

 

 

Presumptive etiology in 26/47: hematoma, traction, limb lengthening, laceration Recovery

 

Complete palsy: full, 36%; partial, 39%; none, 25%

 

Incomplete palsy: full, 39%; partial, 17%; none, 44%

 

 

Leg lengthening is a significant risk factor (conditional logistic regression) Odds ratio -1.1

 

 

Average lengthening 1.7 cm, range -1.1 to 4.4 cm Significant factors (univariate logistic regression)

 

 

 

 

Developmental dysplasia Posttraumatic arthritis Posterior approach Uncemented arthroplasty

 

46% required a walking aid at follow-up

Correct Answer: Prior hip surgery is not a significant risk factor

 

 

894. (3282) Q2-4126:

Which of the following is a significant risk factor for a motor nerve palsy following a primary hip replacement:

 

1) Age <50 years

3) Previous hip surgery

2) Female sex

5) Developmental dysplasia

4) Body mass index greater than 30

 

Farrell and colleagues from the Mayo Clinic recently reported a 0.17% rate of motor nerve palsy following 27,000 primary hip arthroplasties.

The important points to remember are:

 

Nerve distribution: peroneal, 64%; sciatic, 30%; femoral, 6%

 

 

Complete nerve palsy, 62%; incomplete, 38% 87% had a sensory deficit

 

 

Presumptive etiology in 26/47: hematoma, traction, limb lengthening, laceration Recovery

 

Complete palsy: full, 36%; partial, 39%; none, 25%

 

Incomplete palsy: full, 39%; partial, 17%; none, 44%

 

 

Leg lengthening is a significant risk factor (conditional logistic regression) Odds ratio -1.1

 

 

Average lengthening 1.7 cm, range -1.1 to 4.4 cm Significant factors (univariate logistic regression)

 

 

 

 

Developmental dysplasia Posttraumatic arthritis Posterior approach Uncemented arthroplasty

 

 

46% required a walking aid at follow-up Correct Answer: Developmental dysplasia

 

Slide 1 Slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. What is the most likely inheritance pattern of this condition:

 

1) X-linked recessive

3) Autosomal recessive

2) X-linked dominant

5) Sporadic

4) Autosomal dominant

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: Autosomal dominant

 

896. (3284) Q2-4128:

 

 

 

Slide 1 Slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. Which of the following tumor suppressor genes is most likely involved:

 

1) Retinoblastoma (RB)

3) P16INK4A

2) p53

5) EXT1

4) NF1

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: EXT1

 

Slide 1 Slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. The risk of malignancy in this condition is approximately:

 

1. No risk of malignancy

   3) 25%

2. 5% to 10%

   5) 100%

   4) 50%

    

   This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

   Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

    

   In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: 5% to 10%

    

   898. (3286) Q2-4130:

   Which of the following statements is true concerning the nonoperative treatment of moderately displaced fractures (2 mm to 5 mm) that involve >30% of the articular surface (Mason type IIa):

    

   1. Elbow extension loss averages approximately 20° to 30°.

3. More than 80% of patients have no subjective complaints at long-term follow-up.

1. Grip strength is significantly reduced.

5) Proximal radioulnar synostosis occurs in 20% of patients.

4) Patients requiring late radial head excision have significant functional limitations.

 

This long-term follow-up study of 49 patients with Mason type IIa radial head fractures (2 mm to 5 mm displacement, >30% of the articular surface) showed that 82% of patients had no elbow complaints. Only one patient had poor function. The loss of elbow extension was only 3° and the loss of elbow flexion only 2°. The elbow valgus angle averaged 10° in the injured elbow compared to 8° in the noninjured elbow. There was no difference in forearm pronation and only a 2° loss of forearm supination. No difference in elbow strength, grip strength, or forearm circumference was reported. Six of 49 patients (11%) required late radial head excision; two of these patients had no symptoms and four had mild symptoms. The authors recommend nonoperative treatment of Mason type IIa radial head fractures.Correct Answer: More than 80% of patients have no subjective complaints at long-term follow-up.

 

 

Which of the following statements is false following nonoperative treatment of Mason type IIa fractures (2 mm to 5 mm displacement, >30% of the articular surface):

 

1) Proximal radioulnar synostosis is rare.

3) Forearm pronation loss averages 25°.

2) Patients requiring radial head excision have minor functional problems.

5) Elbow strength and forearm circumference are normal.

4) Grip strength is reduced.

 

This long-term follow-up study of 49 patients with Mason type IIa radial head fractures (2 mm to 5 mm displacement, .30% of the articular surface) showed that 82% of patients had no elbow complaints. Only one patient had poor function. The loss of elbow extension was only 3° and the loss of elbow flexion only 2°. The elbow valgus angle averaged 10° in the injured elbow compared to 8° in the noninjured elbow. There was no difference in forearm pronation and only a 2° loss of forearm supination. No difference in elbow strength, grip strength, or forearm circumference was reported. Six of 49 patients (11%) required late radial head excision; two of these patients had no symptoms and four had mild symptoms. The authors recommend nonoperative treatment of Mason type IIa radial head fractures.Correct Answer: Forearm pronation loss averages 25°.

 

 

 

900. (3288) Q2-4132:

Using the technique of homologous recombination in a knockout mouse model in which the receptor activator of nuclear factor-kB ligand (RANKL) or RANK gene is deleted, which of the following conditions will most likely develop:

 

1) Multiple hereditary exostosis

3) Primary osteoporosis

2) Primary hyperparathyroidism

5) Osteopetrosis

4) Secondary osteoporosis

 

The RANKL is the final common denominator of osteoclast activation. Numerous conditions such as bone metastases, multiple myeloma, osteoporosis, hyperparathyroidism, and others result in osteoclast activation. In these conditions, there is an increased expression and release of the RANKL from the surface of the osteoblasts and marrow stromal cells. The RANKL then binds to the RANK receptor on the osteoclast precursor cells, differentiating into active osteoclasts.

 

If one knocks out the RANKL or RANK receptor, then osteoclast precursor cells cannot be activated. As a result, no bone resorption or osteopetrosis occurs.

 

In osteopetrosis, a lack of osteoclasts results in dense bone with virtually no marrow cavity. Correct Answer: Osteopetrosis

 

901. (3289) Q2-4133:

The receptor activator of nuclear factor-kB ligand (RANKL) is expressed on the surface of which of the following cells:

 

1) Osteoclasts

3) Platelets

2) Osteoblasts and marrow stromal cells

5) Vascular endothelial cells

4) Macrophages

 

The RANKL is the final common denominator of osteoclast activation and is expressed on the surface of osteoblasts and marrow stromal cells.

Numerous conditions such as bone metastases, multiple myeloma, osteoporosis, hyperparathyroidism, and others result in osteoclast activation. In these conditions, there is an increased expression and release of the RANKL from the surface of the osteoblasts and marrow stromal cells. The RANKL then binds to the RANK receptor on the osteoclast precursor cells, differentiating into active osteoclasts.

 

Correct Answer: Osteoblasts and marrow stromal cells

 

In transgenic mice, the overproduction of osteoprotegerin (OPG) results in which of the following conditions:

 

1) Multiple hereditary exostoses

3) Secondary hyperparathyroidism

2) Primary hyperparathyroidism

5) Osteopetrosis

4) Primary osteoporosis

 

Osteoprotegerin is a competitive decoy inhibitor that binds the receptor activator of nuclear factor-kB ligand (RANKL), thereby preventing the RANKL from attaching to the RANK receptor on osteoclast precursor cells. The ratio of the RANKL to OPG determines whether osteclast activation occurs.

 

When overproduction of OPG occurs, there is a marked reduction in osteoclast activation. In this scenario, osteopetrosis develops. In osteopetrosis, a lack of osteoclasts results in dense bone with virtually no marrow cavity.

Correct Answer: Osteopetrosis

 

 

903. (3291) Q2-4135:

Which of the following factors are essential for osteoblast differentiation:

 

1) Dihydrofolate reductase

3) Insulin-like growth factor 1

2) Core binding factor alpha 1 (CBFA1 or Runx2)

5) Osteoprotegerin (OPG)

4) Receptor activator of nuclear factor-kB ligand (RANKL)

 

Osteoblasts arise from mesenchymal stem cells. Core binding factor alpha (CBFA1 or Runx2) is a transcription factor that induces most genes that are associated with osteoblast differentiation.Correct Answer: Core binding factor alpha 1 (CBFA1 or Runx2)

 

 

904. (3292) Q2-4136:

Which of the following factors most likely has a role in the production of osteoblastic bone metastases:

 

1) Receptor activator of nuclear factor-kB ligand (RANKL)

3) Osteoprotegerin (OPG)

2) Parathyroid hormone-related protein (PTHrP)

5) Macrophage inflammatory protein (MIP) 1 alpha

4) Endothelin-1

 

Endothelin-1 likely plays a major role in blastic metastases in breast and prostate cancers. Endothelin-1 stimulates bone formation and the proliferation of osteoblasts.

 

The mechanism of bone formation is not nearly as well defined as bone destruction in metastatic bone disease. Correct Answer: Endothelin-1

Which of the following is a marker for osteoclastic activity:

 

1) Serum bone specific alkaline phosphatase

3) Serum type 1 procollagen C-propeptide

2) Serum osteocalcin

5) Serum endothelin-1

4) Urine type 1 collagen cross-linked N-telopeptides

 

The markers of osteoclastic activity are:

 

 

Serum C-terminal telopeptide of type 1 collagen Serum tartrate resistant acid phosphatase

 

 

Urine type 1 collagen cross-linked N-telopeptides Urine C-terminal telopeptide of type 1 collagen

The markers of osteoblastic activity are:

 

 

Serum bone specific alkaline phosphatase Serum osteocalcin

 

 

Serum type 1 procollagen C-propeptide Serum endothelin-1

Correct Answer: Urine type 1 collagen cross-linked N-telopeptides

 

 

906. (4060) Q2-4138:

Which of the following is a marker for osteoblastic activity:

 

1) Serum C-terminal telopeptide of type-1 collagen

3) Urine type-1 collagen cross linked N-telopeptides

2) Serum tartrate resistant acid phosphatase

5) Serum osteocalcin

4) Urine C-terminal telopeptide of type 1 collagen

 

The markers of osteoclastic activity are:

 

 

Serum C-terminal telopeptide of type 1 collagen Serum tartrate resistant acid phosphatase

 

 

Urine type 1 collagen cross-linked N-telopeptides Urine C-terminal telopeptide of type 1 collagen

The markers of osteoblastic activity are:

 

 

Serum bone specific alkaline phosphatase Serum osteocalcin

 

 

Serum type 1 procollagen C-propeptide Serum endothelin-1

Correct Answer: Serum osteocalcin

 

Which of the following is a marker for osteoblastic activity:

 

1) Serum C-terminal telopeptide of type 1 collagen

3) Urine type 1 collagen cross-linked N-telopeptides

2) Serum tartrate resistant acid phosphatase

5) Serum endothelin-1

4) Urine C-terminal telopeptide of type 1 collagen

 

The markers of osteoclastic activity are:

 

 

Serum C-terminal telopeptide of type 1 collagen Serum tartrate resistant acid phosphatase

 

 

Urine type 1 collagen cross-linked N-telopeptides Urine C-terminal telopeptide of type 1 collagen

The markers of osteoblastic activity are:

 

 

Serum bone specific alkaline phosphatase Serum osteocalcin

 

 

Serum type 1 procollagen C-propeptide Serum endothelin-1

 

 

 

 

 

Correct Answer: Serum endothelin-1 908. (3294) Q2-4140:

 

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. The most likely diagnosis is:

 

1) Enchondromatosis

3) Multiple hereditary exostoses

2) Eosinophilic granuloma

5) Spondyloepiphyseal dysplasia

4) Fibrous dysplasia

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: Multiple hereditary exostoses

 

slide 1 slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. What is the most likely inheritance pattern of this condition:

 

1) X-linked recessive

3) Autosomal recessive

2) X-linked dominant

5) Sporadic

4) Autosomal dominant

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: Autosomal dominant

 

910. (3296) Q2-4142:

 

 

 

slide 1 slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. Which of the following tumor suppressor genes is most likely involved:

 

1) Retinoblastoma (RB)

3) P16INK4A

2) p53

5) EXT1

4) NF1

 

This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

 

In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: EXT1

 

slide 1 slide 2

A patientâs upper extremity radiographs are shown in Slide 1 and Slide 2. The risk of malignancy in this condition is approximately:

 

1. No risk of malignancy

   3) 25%

2. 5% to 10%

   5) 100%

   4) 50%

    

   This patient has multiple hereditary exostoses. Note the multiple sessile osteochondromas on the humerus and ulna. A characteristic bowing deformity of the forearm and pseudo-Madelung deformity of the wrist are also present.

   Multiple hereditary exostoses is autosomal dominant. The putative tumor suppressive gene mutation is EXT1, EXT2. The risk of low-grade chondrosarcoma occurring is approximately 10%.

    

   In most patients, the forearm deformity does not cause a major problem and can be treated nonoperatively. Correct Answer: 5% to 10%

    

   912. (3298) Q2-4144:

   Which of the following is an indication for surgery in patients with rheumatoid arthritis of the spine:

    

   1. Posterior atlantodental interval between 14 mm and 16 mm

3. Cervico-medullary angle between 135° and 175°

1. Atlantodental interval >5 mm

5) Posterior atlantodental interval of 13 mm with subaxial subluxation

1. Odontoid migration of 4 mm above McGregorâs line

    

   The review article by Kim and Hilibrand summarized the current indications for decompression and fusion in patients with rheumatoid arthritis and cervical spine disease.

   The indications are:

   1. Progressive neurologic deficit

      1. Myelopathy â wide-based spastic gait, clumsy hands, change in handwriting, difficulty with fine motor control

   2. Severe neck pain with atlantoaxial subluxation, atlantoaxial impaction, or subaxial subluxation

   3. Atlantoaxial subluxation with a posterior atlantodental interval of <14 mm

   4. Atlantoaxial impaction â odontoid migration >5 mm above McGregorâs line

   5. Subaxial subluxation with a sagittal canal diameter <14 mm

   6. Cervicomedullary angle <135°

Correct Answer: Posterior atlantodental interval of 13 mm with subaxial subluxation

 

Which of the following statements is true concerning rheumatoid arthritis:

 

1) Rheumatoid arthritis does not affect life expectancy.

3) Erosion of the odontoid rarely occurs.

2) Men are affected twice as much as women.

5) Rheumatoid arthritis affects approximately 1% of the U.S. population

4) The atlantodental interval is the best prognostic factor for neurologic injury.

 

Rheumatoid arthritis is common and affects 0.5% to 1.5% of the U.S. population. Important points to remember include:

 

 

Women are affected twice as commonly as men. Rheumatoid arthritis reduces life expectancy.

 

Blockade of tumor necrosis alpha can be very effective.

 

The posterior atlantodental interval is more important than the anterior atlantodental interval.

 

A prospective study from Finland showed that over a 20-year period, patients with seropositive rheumatoid arthritis had the following risk of cervical spine disease:

 

 

 

Atlantoaxial subluxation â 23% Atlantoaxial impaction â 26% Subaxial subluxation â 19%

 

Correct Answer: Rheumatoid arthritis affects approximately 1% of the U.S. population

 

 

914. (3300) Q2-4146:

Which of the following is a risk factor for progressive atlantoaxial subluxation in patients with rheumatoid arthritis of the cervical spine:

 

1) Male sex

3) HLA-b27 antigen

2) HLA-dr4 antigen

5) Seronegativity

4) Steroid use

 

In a review article, Kim and Hilibrand list the following as risk factors for progression of atlantoaxial subluxation in rheumatoid arthritis:

 

Male sex

 

 

 

Rheumatoid factor positivity Presence of subcutaneous nodules Rapid loss of carpal height

 

In contrast to the above, HLA-dr4 and HLA-b27 antigens are not significant risk factors. The use of steroids does not appear to be a significant risk factor.

Correct Answer: Male sex

 

Which of the following posterior atlantodental intervals is associated with a very poor neurologic recovery following decompression and fusion:

 

1) <10 mm

3) 11 mm to 13 mm

2) 10 mm to 12 mm

5) 16 mm

4) 14 mm

 

In a review article, Kim and Hilibrand cite the reports of Boden which showed that, when the posterior atlantodental interval was

<10 mm, patients did not experience any neurologic recovery following surgery. In regard to preoperative posterior atlantodental interval, one should remember:

 

<10 mm No recovery

 

>10 mm Recovery of at least one Ranawat grade

 

 

>14 mm Complete recovery Correct Answer: <10 mm

 

916. (3434) Q2-4355:

Osteochondroses of the tarsal navicular or the capitellum in a child is most likely the result of:

 

1) Genetic disorder

3) Benign neoplasm

2) Developmental disorder

5) Vascular insufficiency

4) Repetitive stress

 

The osteochondroses represent disordered growth and function of enchondral ossification under load or stress in a growing child. The causative stress is usually from overuse (eg, pitching). The disordered ossification is often accompanied by deformation of the cartilage and its adjacent interface with bone. In areas where the cartilage is under tension, the term apophysitis is also used.Correct Answer: Repetitive stress

 

 

917. (3445) Q2-4372:

All of the following occur with focal nerve compression except:

 

1) Focal demyelination

3) Conduction block across the site

2) Nerve conduction velocity slowing

5) Small amplitude-short duration motor unit potentials

4) Fibrillation potentials and positive sharp waves

 

With focal nerve compression, focal demyelination is present. The axon remains intact but, with myelin loss, slowing of conduction occurs and a conduction block is possible.

 

Common findings with focal nerve compression include: Focal demyelination

 

 

 

Nerve conduction velocity slowing Conduction block across the site Fibrillation potentials

 

Positive sharp waves

 

High amplitude-long duration motor unit potentials (chronic denervation)

 

In contrast, small amplitude-short duration motor unit potentials are found in myopathy. Correct Answer: Small amplitude-short duration motor unit potentials

Which of the following is typically found on electrodiagnostic testing with denervation of skeletal muscle:

 

1) Complex repetitive discharges

3) Myokymic potentials

2) Myotonic discharges

5) Myotonic discharges and myokymic potentials

4) Positive sharp waves and fibrillations

 

With electrodiagnostic testing, a clinician may find several characteristic features in different disorders: Denervation

 

Fibrillation

 

Positive sharp waves Fasciculations

Neurogenic lesions

 

 

Fasciculations Myokymic potentials

Myopathies

 

 

Complex repetitive discharges Myotonic discharges

Correct Answer: Positive sharp waves and fibrillations

 

 

919. (3447) Q2-4374:

Which of the following factors is crucial for the differentiation of mesenchymal cells to osteoblasts:

 

1) Type X collagen

3) CBAF1/RUNX2

2) Type II collagen

5) Receptor activator of nuclear factor-kB ligand (RANKL)

4) Low level of beta-catenin

 

CBAF1/RUNX2 is a transcription factor that is essential for differentiation of mesenchymal cells to osteoblasts. This transcription factor is expressed during intramembranous bone formation and during hypertrophic phase of enchondral growth.

Cleidiocranial dysplasia is caused by a failure to mineralize the cartilage anlagen. This genetic disorder is caused by a loss of function in CBAF1/RUNX2.

 

Phenotype of cleidocranial dysplasia includes: Short stature

 

Hypoplasia/aplasia of the clavicles

 

 

Delayed ossification and closure of cranial sutures Defects in tooth eruption and extra teeth

Correct Answer: CBAF1/RUNX2

 

Which of the following disorders occurs with a loss of function mutation (heterozygous) in CBAF1/RUNX2:

 

1) Achondroplasia

3) Cleidocranial dysplasia

2) Osteopetrosis

5) Tertiary hyperparathyroidism

4) Primary osteoporosis

 

Cleidocranial dysplasia is caused by a failure to mineralize the cartilage anlagen. This genetic disorder is caused by a loss of function in CBAF1/RUNX2.

 

Phenotype of cleidocranial dysplasia includes: Short stature

 

Hypoplasia/aplasia of the clavicles

 

 

Delayed ossification and closure of cranial sutures Defects in tooth eruption and extra teeth

Correct Answer: Cleidocranial dysplasia

 

 

921. (3449) Q2-4376:

A patient sustains a humeral fracture that results in radial nerve palsy. At which of the following time points would an electrodiagnostic study be performed to check the integrity of the radial nerve:

 

1) Immediately following the injury

3) 14 days following the injury

2) 7 days following the injury

5) 6 to 8 weeks following the injury

4) 21 days following the injury

 

At 6 to 8 weeks following the injury, a clinician should perform an electrodiagnostic study to detect reinnervation. A needle electromyogram will show small amplitude polyphasic motor unit potentials.

 

The following is the typical of sequence of electrodiagnostic findings: Severance of the nerve

 

 

Positive sharp waves and fibrillation potentials at 2 weeks Incomplete nerve injury

 

 

Small amplitude motor unit potentials at 6 to 8 weeks Correct Answer: 6 to 8 weeks following the injury

 

922. (3453) Q2-4381:

Which of the following factors plays a major role in inducing cells to form osteoblasts with resultant intramembranous bone formation:

 

1) Stable beta-catenin

3) Receptor activator of nuclear factor-kB ligand (RANKL)

2) SOX9

5) Type II collagen

4) Osteoprotegerin (OPG)

 

Bone forms from either intramembranous bone formation or enchondral bone formation.

Intramembranous bone formation occurs in the skull, maxilla, mandible, clavicle, and subperiosteal surface of long bones. This is a complex process and is controlled by a signaling pathway called canonical Wnt and sonic hedgehog signaling. Beta-catenin is not degraded, and it enters the cell nucleus to induce genes for bone formation. The two most important transcription factors are CBFA1/RUNX2 and osterix (OSX). Stable beta-catenin drives the process toward intramembranous bone formation.

 

 

Angiogenesis is also important and vascular endothelial factor alpha (VEGF-A) plays an important role in bone formation. Correct Answer: Stable beta-catenin

Which of the following statements is true concerning intraoperative acetabular fractures following uncemented total hip arthroplasty:

 

1) The incidence is highest with an elliptical modular cup design.

3) The incidence is highest with an elliptical monoblock design.

2) The incidence is highest with a true elliptical modular cup design.

5) Plate fixation in addition to augmentation of the cup with screws is often necessary.

4) The location of the fracture is most likely to be anterosuperior.

 

Intraoperative acetabular fractures with uncemented cups are rare. This Mayo Clinic study showed a fracture rate of 3.5% with an elliptical monoblock cup. The rate with the monoblock cup was significantly higher than the elliptical modular and hemispherical modular designs (both <0.5%). The fractures were usually found posterior superior (12/21), direct posterior (posterior wall) (6/21), and much less commonly anterosuperior or medial. If the cup was unstable after the fracture, then it was removed, and another cup with screw fixation was used. All fractures healed uneventfully with no adverse sequelae. The authors recommend under-reaming ≤2 mm regardless of cup design.Correct Answer: The incidence is highest with an elliptical monoblock design.

 

 

924. (3456) Q2-4384:

Which of the following is associated with achondroplasia:

 

1) Heterozygous loss of function mutation, CBF1/RUNX2

3) Parathyroid hormone-related protein (PTHrP) â loss of function mutation

2) Collagen type X mutation

5) PTHrP activating mutation

4) Activating mutation of fibroblast growth factor receptor-3 (FGFR-3)

 

In achondroplasia, an activating mutation of the FGFR-3 is present.

During enchondral growth, the proliferation of the chondrocytes is controlled by fibroblast growth factor (FGF). FGF interacts with a cell surface tyrosine kinase receptor, FGFR-3. An activating mutation causes increased signaling for limitation of cartilage proliferation in the growth plate, resulting in short limbs.

 

The important mutations that cause short stature include: Achondroplasia: Activating mutation of FGFR-3

 

 

 

 

Jansenâs metaphyseal chondrodysplasia: Activating mutation of PTHrP Blomstrandâs chondrodysplasia: Loss of function mutation of PTHrP Cleidocranial dysplasia: Heterozygous loss of function mutation, CBF1/RUNX2 Schmidâs type metaphyseal chondrodysplasia: Type X collagen mutation

 

Correct Answer: Activating mutation of fibroblast growth factor receptor-3 (FGFR-3)

 

 

925. (3458) Q2-4389:

Which of the following is the best diagnostic test to establish the diagnosis of cubital tunnel syndrome:

 

1) Sensory nerve conduction velocity, finger to wrist

3) Mixed nerve conduction velocity, finger to wrist

2) Motor nerve conduction velocity across the elbow

5) Motor conduction, elbow to axilla

4) Motor conduction, Erbâs point to axilla

 

Motor nerve conduction velocity testing across the elbow is the best diagnostic test to establish the diagnosis of cubital tunnel syndrome.Correct Answer: Motor nerve conduction velocity across the elbow

 

Which of the following are typically found following a complete laceration of a peripheral nerve after 3 weeks:

 

1) Fasciculation potentials

3) Myokymic potentials

2) Fibrillation potentials and positive sharp waves

5) Complex repetitive discharges

4) Myotonic discharges

 

A complete laceration of a peripheral nerve is a denervation injury.

With electrodiagnostic testing, a clinician may find several characteristic features in different disorders: Denervation

 

Fibrillation

 

 

Positive sharp waves Fasciculations

Neurogenic lesions

 

 

Fasciculations Myokymic potentials

Myopathies

 

 

Complex repetitive discharges Myotonic discharges

Correct Answer: Fibrillation potentials and positive sharp waves

 

 

927. (3461) Q2-4393:

When the cartilage anlagen is expressed during the process of enchondral ossification, which of the following types of collagen is produced:

 

1) Types I, III

3) Type X

2) Types II, IX, XI

5) Types I, III, X

4) Type I

 

During the time that the cartilage anlagen is formed, the chondrocytes (or mesenchymal cells) produce cartilage-specific collagen. The collagen expression is shifted from the bone collagens (types I, III) to the cartilage collagens (types II, IX, XI).

Important points:

 

Type I: Major bone collagen

 

Types II, IX, and XI: Major cartilage collagens

 

 

Type X: Major collagen of hypertrophying and mineralizing chondrocytes Correct Answer: Types II, IX, XI

Which of the following is associated with Jansenâs metaphyseal chondrodysplasia:

 

1) Heterozygous loss of function mutation, CBF1/RUNX2

3) Parathyroid hormone-related protein (PTHrP) â loss of function mutation

2) Collagen type X mutation

5) PTHrP activating mutation

4) Activating mutation of fibroblast growth factor receptor-3 (FGFR-3)

 

Parathyroid hormone-related protein (PTHrP) has a specific inhibitory effect on chondrocyte differentiation (inability to hypertrophy). During enchondral growth, the chondrocytes hypertrophy and then mineralize to form bone.

Activating mutations of PTHrP cause a decrease in chondrocyte hypertrophy and result in short stature (Jansenâs metaphyseal chondrodysplasia). Blomstrandâs chondrodysplasia involves a loss of function mutation, resulting in accelerated chondrocyte hypertrophy and short stature.

 

Parathyroid hormone-related protein also affects Indian hedgehog signaling while Indian hedgehog induces PTHrP (self-regulating feedback loop). Indian hedgehog is a positive regulator of chondrocyte proliferation and osteoblastic differentiation in the perichondral ring.

 

Correct Answer: PTHrP activating mutation

 

 

929. (3466) Q2-4403:

Which of the following statements is true concerning anterior cruciate ligament (ACL) tears in children with open physes:

 

1) The pattern of ACL failure is the same as adults.

3) The Lachmanâs test is seldom positive.

2) Associated meniscal tears are uncommon.

5) The pivot shift test is seldom positive.

4) The tear often occurs at the tibial insertion.

 

Although ACL injuries are less common in children than adults, this type of knee injury is becoming more common as children are involved in more athletic activities. Important points to remember include:

 

 

In children, the ACL collagen fibers extend from the ligament to epiphyseal cartilage. Many ACL injuries occur at the tibial insertion.

 

 

Tibial eminence avulsion fractures often accompany ACL injury. Associated meniscal injuries are common.

 

 

The physical examination findings are the same as in adults. Bicycle accidents are a common mechanism of injury.

Correct Answer: The tear often occurs at the tibial insertion.

 

 

930. (3468) Q2-4405:

Which of the following is associated with Schmidâs type metaphyseal chondrodysplasia:

 

1) Type X collagen mutation

3) Activating mutation of fibroblast growth factor receptor-3 (FGFR-3)

2) Heterozygous loss of function mutation, CBF1/RUNX2

5) PTHrP loss of function mutation

4) Parathyroid hormone-related protein (PTHrP) activating mutation

 

Type X collagen mutations result in Schmidâs type metaphyseal chondrodysplasia.

Collagen type X is uniquely expressed by hypertrophic chondrocytes. The extracellular matrix that is formed by the hypertrophic chondrocytes is easily degraded. There are high levels of expression of vascular endothelial growth factor A and marked ingrowth of blood vessels, osteoclasts, and osteoblasts. Hypertrophic chondrocytes are resorbed, and the matrix mineralizes. When defects in type X collagen exist, an interruption of normal longitudinal growth occurs.

 

Correct Answer: Type X collagen mutation

 

Which of the following is the most sensitive electrodiagnostic study to establish the diagnosis of carpal tunnel syndrome:

 

1) Nerve conduction across the finger to wrist segment

3) Motor conduction â wrist to elbow

2) Terminal latency

5) Sensory nerve conduction across the palm wrist segment

4) Mixed conduction â wrist to elbow

 

Sensory nerve conduction across the palm to wrist segment is the most sensitive electrodiagnostic finding in carpal tunnel syndrome.

 

The accuracy of electrodiagnostic testing is good: Sensitivity â 85% to 90%

 

Specificity â 95%

Correct Answer: Sensory nerve conduction across the palm wrist segment

 

 

932. (3497) Q2-4441:

Which of the following is uniquely expressed by hypertrophying chondrocytes during longitudinal growth:

 

1) Stable beta-catenin

3) CBAF1/RUNX2

2) Type X collagen

5) Type II collagen

4) Parathyroid hormone-related protein (PTHrP)

 

Collagen type X is uniquely expressed by hypertrophic chondrocytes. The extracellular matrix that is formed by the hypertrophic chondrocytes is easily degraded. There are high levels of expression of VEGFA and marked ingrowth of blood vessels, osteoclasts, and osteoblasts. The hypertrophic chondrocytes are resorbed, and the matrix mineralizes. When defects in type X collagen are present, then an interruption of normal longitudinal growth occurs.

 

 

Type X collagen mutations result in Schmidâs type metaphyseal chondrodysplasia. Correct Answer: Type X collagen

 

933. (3499) Q2-4445:

Which of the following factors is critical for normal enchondral growth in regard to hypertrophying chondrocytes:

 

1) Stable beta-catenin

3) CBAF1/RUNX2

2) Parathyroid hormone-related protein (PTHrP)

5) Osterix

4) Type X collagen/vascular endothelial growth factor A (VEGFA)

 

Collagen type X is uniquely expressed by hypertrophic chondrocytes. The extracellular matrix that is formed by the hypertrophic chondrocytes is easily degraded. There are high levels of expression of VEGFA and marked ingrowth of blood vessels, osteoclasts, and osteoblasts. The hypertrophic chondrocytes are resorbed, and the matrix mineralizes. When defects in type X collagen are present, then an interruption of normal longitudinal growth occurs.

 

 

Type X collagen mutations result in Schmidâs type metaphyseal chondrodysplasia. Correct Answer: Type X collagen/vascular endothelial growth factor A (VEGFA)

Which of the following cells is primarily affected in patients with Gaucher disease:

 

1) Osteoblast

3) Osteocyte

2) Osteoclast

5) Macrophage

4) Platelet

 

Gaucher disease is caused by an accumulation of glucocerebrosides (glucosylceramide) in macrophages. The specific enzyme deficiency is glucocerebrosidase (acid beta-glucosidase, lysosomal enzyme). The disease inheritance pattern is autosomal recessive.

 

Erlenmeyer flask deformities of the metaphyses are a common bone remodeling condition present in patients with Gaucher disease.

Clinical manifestations include pancytopenia, thrombocytopenia, and specific bone conditions such as osteonecrosis, bone crises, and fractures. Patients often have easy bruising and fatigability.

 

Patients with Gaucher disease are treated by replacement of the deficient enzyme. Correct Answer: Macrophage

 

935. (3514) Q2-4468:

In patients with Gaucher disease, which of the following substances accumulates abnormally in macrophages:

 

1) Dermatan sulfate

3) Keratin sulfate

2) Heparan sulfate

5) Glucocerebrosides

4) Chondroitin sulfate

 

Gaucher disease is caused by an accumulation of glucocerebrosides (glucosylceramide) in macrophages. The specific enzyme deficiency is glucocerebrosidase (acid beta-glucosidase, lysosomal enzyme). The disease inheritance pattern is autosomal recessive.

 

Erlenmeyer flask deformities of the metaphyses are a common bone remodeling condition present in patients with Gaucher disease.

Clinical manifestations include pancytopenia, thrombocytopenia, and specific bone conditions such as osteonecrosis, bone crises, and fractures. Patients often have easy bruising and fatigability.

Patients with Gaucher disease are treated by replacement of the deficient enzyme. The other answer choices refer to patients with mucopolysaccharidoses:

Syndrome Glycosaminoglycans

Hurler syndrome Dermatan sulfate and heparan sulfate Hunter syndrome Heparan and dermatan sulfate Sanfilippo syndrome Heparan sulfate

Morquio syndrome Keratin sulfate Maroteaux-Lamy syndrome Dermatan sulfate

Correct Answer: Glucocerebrosides

 

Which of the following enzyme deficiencies occurs in patients with Gaucher disease:

 

1) Alpha-L-iduronidase

3) Glucocerebrosidase

2) Beta-glucuronidase

5) Homogentisic acid oxidase

4) Acid phosphatase

 

Gaucher disease is caused by an accumulation of glucocerebrosides (glucosylceramide) in macrophages. The specific enzyme deficiency is glucocerebrosidase (acid beta-glucosidase, lysosomal enzyme). The disease inheritance pattern is autosomal recessive.

 

Erlenmeyer flask deformities of the metaphyses are a common bone remodeling condition present in patients with Gaucher disease.

Clinical manifestations include pancytopenia, thrombocytopenia, and specific bone conditions such as osteonecrosis, bone crises, and fractures. Patients often have easy bruising and fatigability.

 

Patients with Gaucher disease are treated by replacement of the deficient enzyme. The other answer choices occur in different conditions:

Syndrome Enzyme

Hurler syndrome Alpha-L-iduronidase

Sly syndrome Beta-glucuronidase Alkaptonuria (ochronosis) Homogentisic acid oxidase

Correct Answer: Glucocerebrosidase 937. (3516) Q2-4470:

Which of the following is the inheritance pattern of Gaucher disease:

 

1) Autosomal recessive

3) X-linked dominant

2) Autosomal dominant

5) Sporadic

4) X-linked recessive

 

Gaucher disease is caused by an accumulation of glucocerebrosides (glucosylceramide) in macrophages. The specific enzyme deficiency is glucocerebrosidase (acid beta-glucosidase, lysosomal enzyme). The disease inheritance pattern is autosomal recessive.

 

Erlenmeyer flask deformities of the metaphyses are a common bone remodeling condition present in patients with Gaucher disease.

Clinical manifestations include pancytopenia, thrombocytopenia, and specific bone conditions such as osteonecrosis, bone crises, and fractures. Patients often have easy bruising and fatigability.

 

Patients with Gaucher disease are treated by replacement of the deficient enzyme. Correct Answer: Autosomal recessive

Which of the following criteria are used to define osteoporosis:

 

1) Low bone mass, inadequate mineralization, normal micro architecture

3) Normal bone mass, normal mineralization, abnormal micro architecture

2) Low bone mass, normal mineralization, abnormal micro architecture

5) Low bone mass, normal mineralization, normal micro architecture

4) Normal bone mass, abnormal mineralization, abnormal micro architecture

 

 

The essential features of osteoporosis include: Low bone mass

 

 

Normal mineralization Abnormal micro architecture

Osteoporosis is defined by the World Health Organization by comparing a patient's bone mineral density (BMD) to that of patients at the time of peak bone mass (T-score).

 

Normal bone mineral density is within 1 SD

 

 

Low bone mass (osteopenia) is between 1 SD and 2.5 SD below mean peak bone mass Osteoporosis is more than 2.5 SD below mean peak bone mass

Correct Answer: Low bone mass, normal mineralization, abnormal micro architecture

 

 

939. (3518) Q2-4472:

A 65-year-old woman has a bone mineral density test. Which of the following T-scores is diagnostic of osteoporosis:

 

1) T-score within 0.5 SD below the mean

3) T-score 1 SD to 2 SD below the mean

2) T-score within 1 SD below the mean

5) T-score more than 2.5 SD below the mean

4) T-score 1 SD to 2.5 SD below the mean

 

 

The essential features of osteoporosis include: Low bone mass

 

 

Normal mineralization Abnormal micro architecture

Osteoporosis is defined by the World Health Organization by comparing a patient's bone mineral density (BMD) to that of patients at the time of peak bone mass (T-score).

 

Normal bone mineral density is within 1 SD

 

 

Low bone mass (osteopenia) is between 1.0 SD to 2.5 SD below individuals at peak bone mass Osteoporosis is more than 2.5 SD below mean peak bone mass

Correct Answer: T-score more than 2.5 SD below the mean

 

 

 

1) CBFA1, COL2A1, and COMP

3) CBFA1, FGFR3

2) COL10A1, FGFR3

5) COL9A2, COMP, and FGFR3

4) COL1A1, VDR, and LRP5

 

 

The essential features of osteoporosis include: Low bone mass

 

 

Normal mineralization Abnormal micro architecture

The causes of osteoporosis are multifactorial; genetic predisposition may be important. The genes associated with the development of osteoporosis include:

 

 

COL1A1 - Collagen 1 alpha 1 (main bone collagen) VDR - Vitamin D receptor

 

LRP5 - Low density lipoprotein receptor related protein The associations of several other genes include:

 

 

CBFA1 - Cleidocranial dysplasia COL2A1 - Achondrogenesis

 

COMP - Multiple epiphyseal dysplasia

 

 

COL10A1 - Schmid metaphyseal chondrodysplasia FGFR3 - Achondroplasia

 

 

COL9A2 - Multiple epiphyseal dysplasia Correct Answer: COL1A1, VDR, and LRP5

 

941. (3520) Q2-4474:

Which of the following dosages are correct in regard to the necessary daily calcium and vitamin D intake in patients between 19 and 50 years of age:

 

1) Calcium 1000 mg; vitamin D 400 IU

3) Calcium 1200 mg; vitamin D 200 IU

2) Calcium 1600 mg; vitamin D 400 IU

5) Calcium 2000 mg; vitamin D 1000 IU to 2000 IU

4) Calcium 1400 mg; vitamin D 400 IU

 

Appropriate amounts of calcium and vitamin D are crucial for good bone health. All therapeutic interventions for patients with osteoporosis require that calcium and vitamin D intake are adequate. The current recommendations for calcium and vitamin D are:

 

 

 

 

Ages 10-19 â Calcium 1000 mg; vitamin D 200 IU Ages 19-50 â Calcium 1200 mg; vitamin D 200 IU Ages 50-79 â Calcium 1400 mg; vitamin D 400 IU

 

 

Osteoporotic patient â Calcium 2000 mg; vitamin D 1000 IU to 2000 IU Correct Answer: Calcium 1200 mg; vitamin D 200 IU

osteoporosis:

 

1) Calcium 1000 mg; vitamin D 400 IU

3) Calcium 1200 mg; vitamin D 200 IU

2) Calcium 1600 mg; vitamin D 400 IU

5) Calcium 2000 mg, vitamin D 1000 IU to 2000 IU

4) Calcium 1400 mg; vitamin D 400 IU

 

Appropriate amounts of calcium and vitamin D are crucial for good bone health. All therapeutic interventions for patients with osteoporosis require that calcium and vitamin D intake are adequate. The current recommendations for calcium and vitamin D are:

 

 

 

 

Ages 10-19â Calcium 1000 mg; vitamin D 200 IU Ages 19-50 â Calcium 1200 mg; vitamin D 200 IU Ages 50-79 â Calcium 1400 mg; vitamin D 400 IU

 

 

Osteoporotic patient â Calcium 2000 mg; vitamin D 1000 IU to 2000 IU Correct Answer: Calcium 1400 mg; vitamin D 400 IU

 

943. (3522) Q2-4476:

Which of the following is the correct daily dietary intake of calcium and vitamin D in a patient older than 65 years of age with osteoporosis:

 

1) Calcium 1000 mg; vitamin D 400 IU

3) Calcium 1200 mg; vitamin D 200 IU

2) Calcium 1600 mg; vitamin D 400 IU

5) Calcium 2000 mg; vitamin D 1000 IU to 2000 IU

4) Calcium 1400 mg; vitamin D 400 IU

 

Appropriate amounts of calcium and vitamin D are crucial for good bone health. All therapeutic interventions for patients with osteoporosis require that calcium and vitamin D intake are adequate. The current recommendations for calcium and vitamin D are:

 

 

 

 

Ages 10-19 â Calcium 1000 mg; vitamin D 200 IU Ages 19-50 â Calcium 1200 mg; vitamin D 200 IU Ages 50-79 â Calcium 1400 mg; vitamin D 400 IU

 

 

Osteoporotic patient â Calcium 2000 mg; vitamin D 1000 IU to 2000 IU Correct Answer: Calcium 2000 mg; vitamin D 1000 IU to 2000 IU

postmenopausal osteoporosis:

 

1) Oral bisphosphonates

3) Subcutaneous parathyroid hormone (PTH)

2) Parenteral bisphosphonates

5) Oral vitamin D supplementation

4) Nasal calcitonin

 

Parathyroid hormone is the only FDA-approved anabolic method for the treatment of osteoporosis. Parathyroid hormone causes bone resorption and bone formation. The net effect is an increase in bone formation.

The indications for PTH therapy include:

 

 

High-risk patients for fracture (bone mineral density, T-score less than -3.0) Patients with refractory osteoporosis

 

Patients who cannot tolerate treatment with other methods The contraindications to PTH therapy include:

 

 

Patients at risk for developing osteosarcoma Pagetâs disease

 

 

Following irradiation of bone Children with open physes

 

 

Patients with hyperparathyroidism Patients with metastatic bone disease

Correct Answer: Subcutaneous parathyroid hormone (PTH)

 

 

945. (3524) Q2-4478:

Which of the following therapies also has a significant analgesic effect in the treatment of women with postmenopausal osteoporosis:

 

1) Oral bisphosphonate

3) Subcutaneous parathyroid hormone

2) Parenteral bisphosphonate

5) Oral vitamin D supplementation

4) Nasal calcitonin

 

Calcitonin is produced by the C cells of the thyroid gland. Although the exact physiologic function of calcitonin is unknown, this hormone has a powerful inhibitory effect on the osteoclast.

 

The effects of calcitonin on the osteoclast include: Flattening of the ruffled border

 

Withdrawal of the osteoclast from the bone surface

Calcitonin can be used as a treatment for osteoporosis. Salmon calcitonin is given intranasally. In addition to inhibiting bone resorption, there is a significant analgesic effect, especially in osteoporotic patients with vertebral fractures.

Correct Answer: Nasal calcitonin

 

 

946. (3525) Q2-4479:

Which of the following complications may occur following bisphosphonate therapy:

 

1) Increase in hip fractures

3) Increase in falls

2) Increase in vertebral fractures

5) Impaired fracture healing

4) Osteonecrosis of the jaw

 

A rare, but significant, skeletal complication of bisphosphonate therapy is osteonecrosis of the jaw. Osteonecrosis of the jaw occurs more commonly in patients with metastatic bone disease who receive monthly treatments and tends to occur following major dental work. Patients should be queried about the condition of their teeth prior to starting bisphosphonate therapy.Correct Answer: Osteonecrosis of the jaw

 

 

947. (3526) Q2-4480:

The mechanism of action of nitrogen-containing bisphosphonates is:

 

1) Toxic analogs of adenosine triphosphate (ATP)

3) Increased production of osteoprotegerin

2) Inhibition of protein prenylation

5) Decreased production of RANK receptor

4) Decreased production of receptor activator of nuclear factor-kB ligand (RANKL)

 

The mechanism of action of nitrogen-containing bisphosphonates is inhibition of protein prenylation. These agents cause programmed cell death of the osteoclast (apoptosis).

The nitrogen-containing bisphosphonates specifically inhibit farnesyl pyrophosphatase and prevent post-translational prenylation of guanosine triphosphate-binding proteins. Nitrogen-containing bisphosphonates disrupt the ruffled border and microtubules of the osteoclast.

 

 

The non-nitrogen containing bisphosphonates (etidronate, clodronate) produce toxic analogs of ATP. Correct Answer: Inhibition of protein prenylation

 

948. (3527) Q2-4481:

Which of the following is the most common adverse effect of bisphosphonate therapy:

 

1) Osteonecrosis of the jaw

3) Fever and myalgia

2) Hypocalcemia

5) Diarrhea

4) Pruritic rash

 

The most common adverse effect of bisphosphonate therapy is fever and myalgia. When taken orally, bisphosphonates must be taken while fasting, with 8 oz of water, and the patient must remain upright for 30 minutes. Because these medications may cause esophageal irritation and possible erosion, they must be used carefully or not at all in patients with disorders of esophageal motility.

 

A rare, but significant, skeletal complication of bisphosphonate therapy is osteonecrosis of the jaw. Osteonecrosis of the jaw occurs more commonly in patients with metastatic bone disease who receive monthly treatments and tends to occur following major dental work. Patients should be queried about the condition of their teeth prior to starting bisphosphonate therapy.

Correct Answer: Fever and myalgia

 

 

 

1) Patients with refractory postmenopausal osteoporosis

3) Patients with bone loss following anti-resorptive therapies

2) Patients at high risk for osteoporotic fractures

5) Men at high risk for osteoporotic fractures

4) Patients with Pagetâs disease

 

Parathyroid hormone is the only FDA-approved anabolic method for the treatment of osteoporosis. Parathyroid hormone causes bone resorption and bone formation. The net effect is an increase in bone formation.

The indications for PTH therapy include:

 

 

High-risk patients for fracture (bone mineral density, T-score less than -3.0) Patients with refractory osteoporosis

 

Patients who cannot tolerate treatment with other methods The contraindications to PTH therapy include:

 

 

Patients at risk for developing osteosarcoma Pagetâs disease

 

 

Following irradiation of bone Children with open physes

 

 

Patients with hyperparathyroidism Patients with metastatic bone disease

Correct Answer: Patients with Pagetâs disease

 

 

950. (3529) Q2-4483:

Diphosphonates are contraindicated in patients with which of the following conditions:

 

1) Pagetâs disease

3) Hypocalcemia

2) Postmenopausal osteoporosis

5) Polyostotic fibrous dysplasia

4) Multiple myeloma

 

The mechanism of action of nitrogen-containing bisphosphonates is inhibition of protein prenylation. These agents cause programmed cell death of the osteoclast (apoptosis).

The nitrogen-containing bisphosphonates specifically inhibit farnesyl pyrophosphatase and prevent post-translational prenylation of guanosine triphosphate-binding proteins. Nitrogen-containing bisphosphonates disrupt the ruffled border and microtubules of the osteoclast.

 

Diphosphonates halt the osteoclast from resorbing bone and increasing the serum calcium level by resorbing bone and releasing the inorganic matrix. Diphosphonates are contraindicated in patients with hypocalcemia because they further lower the serum calcium level.

 

Diphosphonates are used in the treatment of: Pagetâs disease

 

 

Postmenopausal osteoporosis Multiple myeloma

 

 

Metastatic bone disease Polyostotic fibrous dysplasia

Correct Answer: Hypocalcemia

 

 

 

1) Osteoblast activation

3) Osteoclast apoptosis

2) Osteocyte activation

5) Increased production of osteoprotegerin

4) Decreased production of receptor activator of nuclear factor-kB ligand (RANKL)

 

The mechanism of action of nitrogen-containing bisphosphonates is inhibition of protein prenylation. These agents cause programmed cell death of the osteoclast (apoptosis).

The nitrogen-containing bisphosphonates specifically inhibit farnesyl pyrophosphatase and prevent post-translational prenylation of guanosine triphosphate-binding proteins. Nitrogen-containing bisphosphonates disrupt the ruffled border and microtubules of the osteoclast.

 

Diphosphonates halt the osteoclast from resorbing bone and increasing the serum calcium level by resorbing bone and releasing the inorganic matrix. Diphosphonates are contraindicated in patients with hypocalcemia because they further lower the serum calcium level.

 

 

Diphosphonates do not influence RANKL or osteoprotegerin function or production. Correct Answer: Osteoclast apoptosis

 

952. (3531) Q2-4485:

The mechanism of action of nitrogen-containing bisphosphonates is:

 

1) Toxic analogs of adenosine triphosphate

3) Increased production of osteoprotegerin

2) Decreased production of receptor activator of nuclear factor-kB ligand (RANKL)

5) Inhibition of farnesyl pyrophosphatase

4) Decreased production of RANK receptor

 

The mechanism of action of nitrogen-containing bisphosphonates is inhibition of protein prenylation. These agents cause programmed cell death of the osteoclast (apoptosis).

The nitrogen-containing bisphosphonates specifically inhibit farnesyl pyrophosphatase and prevent post-translational prenylation of guanosine triphosphate-binding proteins. Nitrogen-containing bisphosphonates disrupt the ruffled border and microtubules of the osteoclast.

 

Diphosphonates halt the osteoclast from resorbing bone and increasing the serum calcium level by resorbing bone and releasing the inorganic matrix. Diphosphonates are contraindicated in patients with hypocalcemia because they further lower the serum calcium level.

 

 

Diphosphonates do not influence RANKL or osteoprotegerin function or production. Correct Answer: Inhibition of farnesyl pyrophosphatase

 

 

1) White race

3) Low height

2) Low body weight

5) Maternal/paternal history of a hip fracture

4) Glucocorticoid use

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

 

Anticonvulsant, antidepressant use Correct Answer: Low height

 

954. (3533) Q2-4487:

Which of the following are the most significant risk factors for osteoporosis:

 

1) Increasing age, female gender, low body weight

3) Increasing age, black race, male gender

2) Increasing age, female gender, high body weight

5) Male gender, white race, high body weight

4) Male gender, black race, high body weight

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

Anticonvulsant, antidepressant use

Correct Answer: Increasing age, female gender, low body weight

 

 

 

1) White race

3) Low height

2) Low body weight

5) Maternal/paternal history of hip fracture

4) Glucocorticoid use

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

 

Anticonvulsant, antidepressant use Correct Answer: Low height

 

956. (3535) Q2-4489:

Which of the following is a significant risk factor for osteoporosis:

 

1) Black race

3) Low height

2) High body weight

5) High protein intake

4) Glucocorticoid use

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

 

Anticonvulsant, antidepressant use Correct Answer: Glucocorticoid use

 

 

1) Black race

3) Low height

2) High body weight

5) Maternal/paternal history of hip fracture

4) High protein intake

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

Anticonvulsant, antidepressant use

Correct Answer: Maternal/paternal history of hip fracture

 

 

958. (3537) Q2-4491:

Which of the following are significant risk factors for osteoporosis:

 

1) Increasing age, high body weight, female gender

3) Increasing age, low body weight, white race

2) Increasing age low body weight, male gender

5) Female gender, black race, high body weight

4) Female gender, white race, high body weight

 

 

The most important risk factors for osteoporosis are: Increasing age (geriatric patient)

 

 

Female gender Early menopause

 

 

 

White race (fair-skinned individuals) Maternal/paternal history of hip fracture Low body weight

 

 

 

 

Cigarette smoking Glucocorticoid use Excessive alcohol use Low protein intake

 

Anticonvulsant, antidepressant use

Correct Answer: Increasing age, low body weight, white race

 

 

 

1) 10 to 20 years of age

3) 30 to 40 years of age

2) 20 to 30 years of age

5) 50 to 60 years of age

4) 40 to 50 years of age

 

Peak bone mass is achieved when puberty ends, usually between 20 and 30 years of age. Skeletal health is dependent upon peak bone mass because bone mass declines as an individual ages.

The greatest period of bone loss is the time of estrogen withdrawal in women. A decrease in estrogen levels has several consequences, including:

 

 

Decreased renal calcium absorption Decreased calcium absorption

Correct Answer: 20 to 30 years of age

 

 

960. (3702) Q2-7482:

Which of the following is false concerning fibroblast growth factor receptor 3 (FGFR3) physiology and related disorders:

 

1) Autosomal recessive inheritance

3) 70% are new mutations

2) Gain in function mutations

5) Ligand binding results in phosphorylation of the tyrosine kinase domain

4) Receptor is active even without ligand binding

 

I. Important facts concerning FGFR3 physiology and disorders

1. Gain in function mutation results in achondroplasia

   1. Point mutation

   2. Homogenous (single, constant amino acid change)

   3. Receptor is active even without ligand binding

   4. Autosomal dominant

2. Regulates cell growth, proliferation, and differentiation

3. Ligand binding results in phosphorylation of the tyrosine kinase domain

4. Activation of the receptor limits enchondral ossification

    

5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice) Correct Answer: Autosomal recessive inheritance

 

 

1) Autosomal recessive inheritance

3) Majority of patients with achondroplasia have an inherited mutation

2) Loss of function mutation

5) Receptor activation enhances enchondral ossification

4) Receptor is active even without ligand binding

 

I. Important facts concerning FGFR3 physiology and disorders

1. Gain in function mutation results in achondroplasia

   1. Point mutation

   2. Homogenous (single, constant amino acid change)

   3. Receptor is active even without ligand binding

   4. Autosomal dominant

2. Regulates cell growth, proliferation, and differentiation

3. Ligand binding results in phosphorylation of the tyrosine kinase domain

4. Activation of the receptor limits enchondral ossification

    

5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice) Correct Answer: Receptor is active even without ligand binding

 

962. (3704) Q2-7484:

Which of the following is true concerning fibroblast growth factor receptor 3 (FGFR3) physiology and related disorders:

 

1) Autosomal recessive inheritance

3) Majority of patients with achondroplasia have an inherited mutation

2) Gain of function mutation

5) Receptor activation enhances enchondral ossification

4) Heterogeneous disorder with many different mutations

 

I. Important facts concerning FGFR3 physiology and disorders

1. Gain in function mutation results in achondroplasia

   1. Point mutation

   2. Homogenous (single, constant amino acid change)

   3. Receptor is active even without ligand binding

   4. Autosomal dominant

2. Regulates cell growth, proliferation, and differentiation

3. Ligand binding results in phosphorylation of the tyrosine kinase domain

4. Activation of the receptor limits enchondral ossification

    

5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice) Correct Answer: Gain of function mutation

 

1) Autosomal dominant inheritance

3) 70% are new mutations

2) Gain in function mutations

5) Ligand binding results in phosphorylation of the tyrosine kinase domain

4) Receptor activation enhances enchondral ossification

 

I. Important facts concerning FGFR3 physiology and disorders

1. Gain in function mutation results in achondroplasia

   1. Point mutation

   2. Homogenous (single, constant amino acid change)

   3. Receptor is active even without ligand binding

   4. Autosomal dominant

2. Regulates cell growth, proliferation, and differentiation

3. Ligand binding results in phosphorylation of the tyrosine kinase domain

4. Activation of the receptor limits enchondral ossification

    

5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice) Correct Answer: Receptor activation enhances enchondral ossification

 

964. (3706) Q2-7486:

Which of the following is false concerning fibroblast growth factor receptor 3 (FGFR3) physiology and related disorders:

 

1) Autosomal dominant inheritance

3) 70% are new mutations

2) Loss in function mutations

5) Ligand binding results in phosphorylation of the tyrosine kinase domain

4) Receptor activation limits enchondral ossification

 

1. Important facts concerning FGFR3 physiology and disorders

   1. Gain in function mutation results in achondroplasia

      1. Point mutation

      2. Homogenous (single, constant amino acid change)

      3. Receptor is active even without ligand binding

      4. Autosomal dominant

   2. Regulates cell growth, proliferation, and differentiation

   3. Ligand binding results in phosphorylation of the tyrosine kinase domain

   4. Activation of the receptor limits enchondral ossification

       

   5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice) Correct Answer: Loss in function mutations

       

       

      1) Osteogenesis imperfecta

      3) Spondyloepiphyseal dysplasia

      2) Multiple epiphyseal dysplasia

      5) Osteopetrosis

      4) Achondroplasia

       

2. Achondroplasia is the most homogeneous disorder in regard to the point mutation (single amino acid point mutation – arginine to glycine)

   1. The defect is a gain in function of the FGFR3

   2. FGFR3 regulates bone growth by limiting enchondral ossification

   3. The phenotype of achondroplasia is:

      1. Varus knee deformity

      2. Spinal stenosis

          

      3. Atlantoaxial instability Correct Answer: Achondroplasia

 

966. (3708) Q2-7488:

Which of the following is the function of fibroblast growth factor receptor 3 (FGFR3):

 

1) Cartilage cell proliferation and migration (through calcium-dependent proteoglycan binding)

3) Transport of sulfate into cells

2) Regulates bone growth by limiting enchondral ossification

5) Tumor-suppressor gene to control cell growth and differentiation

4) Formation of structural glycoprotein for elastin-containing micro-fibrils

 

Fibroblast growth factor receptor 3 regulates bone growth by limiting enchondral ossification. The other responses refer to:

 

Cartilage oligomeric matrix protein (COMP): Cartilage cell proliferation and migration (through calcium-dependent proteoglycan binding)

 

 

Diastrophic dysplasia sulfate transporter gene (DTDST): Transport of sulfate into cells; needed for proteoglycan production Fibrillin (FBN1): Formation of structural glycoprotein (fibrillin) for elastin-containing micro-fibrils

 

Neurofibromin (NF-1) - tumor suppressor gene to control cell growth and differentiation; negatively regulates the gene RAS o RAS causes cell proliferation

Correct Answer: Regulates bone growth by limiting enchondral ossification

 

 

 

1) Café au lait spots, pseudoarthrosis of tibia, and scoliosis

3) Proximal muscle weakness and calf hypertrophy

2) Cavovarus feet, areflexia, and distal motor wasting

5) Knee varus and spinal stenosis

4) Dolichostenomelia and scoliosis

 

 

The phenotype of achondroplasia includes: Varus knee deformity

 

 

Spinal stenosis Atlantoaxial instability

The other responses:

 

 

 

 

Neurofibromatosis: Café au lait spots, pseudoarthrosis of tibia and scoliosis Charcot-Marie-Tooth disease: Cavovarus feet, areflexia, and distal motor wasting Duchenne muscular dystrophy: Proximal muscle weakness and calf hypertrophy Marfanâs syndrome: Dolichostenomelia and scoliosis

 

Correct Answer: Knee varus and spinal stenosis

 

 

968. (3710) Q2-7490:

In a mouse model, if the gene for fibroblast growth factor receptor 3 (FGFR3) is knocked out, which of the following occurs:

 

1) Marked inhibition of enchondral ossification

3) Marked decrease in sulfate transport into the cells

2) Absence of bilateral clavicles

5) Defects in limb development and patterning (synpolydactyly)

4) Increased vertebral height and long bone length

 

1. Important facts concerning fibroblast growth factor receptor 3 (FGFR3) physiology and disorders

   1. Gain in function mutation results in achondroplasia

      1. Point mutation

      2. Homogenous (single, constant amino acid change)

      3. Receptor is active even without ligand binding

      4. Autosomal dominant

   2. Regulates cell growth, proliferation, and differentiation

   3. Ligand binding results in phosphorylation of the tyrosine kinase domain

   4. Activation of the receptor limits enchondral ossification

   5. Deficiency of the receptor results in elongation of the vertebral column and long bones (knockout mice)

2. The other responses

   1. Runx2 (Cbaf1) deficiency: Cleidocranial dysplasia, absent clavicles

   2. Diastrophic dysplasia sulfate transporter gene (DTDST): Transport of sulfate into cells; needed for proteoglycan production

       

   3. Hoxd-13 deficiency: Defects in development and patterning limb, results in synpolydactyly Correct Answer: Increased vertebral height and long bone length

 

 

1) Mutation in Type I collagen gene

3) Mutation in the sulfate transporter gene

2) Mutation in the fibrillin gene

5) Mutation in fibroblast growth factor receptor 3 gene

4) Mutation in Type IX collagen gene

 

One should remember the important mutations that occur in musculoskeletal conditions:

1. FGFR3 mutation: Achondroplasia

2. Type IX collagen mutation: Multiple epiphyseal dysplasia (MED)

3. WISP3 mutation: Spondyloepiphyseal dysplasia with progressive osteoarthropathy

4. Type II collagen mutation: Stickler syndrome

5. Sulfate transporter gene mutation: Diastrophic dysplasia

6. Fibrillin gene mutation: Marfanâs syndrome

7. Type V collagen mutation: Ehlers-Danlos syndrome

8. Type I collagen mutation: Osteogenesis imperfecta

Correct Answer: Mutation in fibroblast growth factor receptor 3 gene

 

 

970. (3712) Q2-7492:

Which of the following mutations occurs in patients with Ehlers-Danlos syndrome:

 

1) FGFR3 mutation

3) Type V collagen mutation

2) Type II collagen mutation

5) Type IX collagen mutation

4) Sulfate transporter gene mutation

 

 

One should remember the important mutations that occur in musculoskeletal conditions: FGFR3 mutation: Achondroplasia

 

Type IX collagen mutation: Multiple epiphyseal dysplasia (MED)

 

 

WISP3 mutation: Spondyloepiphyseal dysplasia with progressive osteoarthropathy Type II collagen mutation: Stickler syndrome

 

 

Sulfate transporter gene mutation: Diastrophic dysplasia Fibrillin gene mutation: Marfanâs syndrome

 

 

Type V collagen mutation: Ehlers-Danlos syndrome Type I collagen mutation: Osteogenesis imperfecta

Correct Answer: Type V collagen mutation

 

 

 

1) Type II collagen mutation

3) Type I collagen mutation

2) Type V collagen mutation

5) Fibrillin gene mutation

4) Sulfate transporter gene mutation

 

 

One should remember the important mutations that occur in musculoskeletal conditions: FGFR3 mutation: Achondroplasia

 

Type IX collagen mutation: Multiple epiphyseal dysplasia (MED)

 

 

WISP3 mutation: Spondyloepiphyseal dysplasia with progressive osteoarthropathy Type II collagen mutation: Stickler syndrome

 

 

Sulfate transporter gene mutation: Diastrophic dysplasia Fibrillin gene mutation: Marfanâs syndrome

 

 

Type V collagen mutation: Ehlers-Danlos syndrome Type I collagen mutation: Osteogenesis imperfecta

Correct Answer: Sulfate transporter gene mutation

 

 

972. (3714) Q2-7494:

Which of the following mutations occurs in patients with spondyloepiphyseal dysplasia with progressive osteoarthropathy:

 

1) Type IX collagen mutation

3) Type I collagen mutation

2) Type II collagen mutation

5) WISP3 mutation

4) Type V collagen mutation

 

 

One should remember the important mutations that occur in musculoskeletal conditions: FGFR3 mutation: Achondroplasia

 

Type IX collagen mutation: Multiple epiphyseal dysplasia (MED)

 

 

WISP3 mutation: Spondyloepiphyseal dysplasia with progressive osteoarthropathy Type II collagen mutation: Stickler syndrome

 

 

Sulfate transporter gene mutation: Diastrophic dysplasia Fibrillin gene mutation: Marfanâs syndrome

 

 

Type V collagen mutation: Ehlers-Danlos syndrome Type I collagen mutation: Osteogenesis imperfecta

Correct Answer: WISP3 mutation

 

 

 

1) FGFR3 mutation

3) Type II collagen mutation

2) Type IX collagen mutation

5) Type I collagen mutation

4) Type V collagen mutation

 

 

One should remember the important mutations that occur in musculoskeletal conditions: FGFR3 mutation: Achondroplasia

 

Type IX collagen mutation: Multiple epiphyseal dysplasia (MED)

 

 

WISP3 mutation: Spondyloepiphyseal dysplasia with progressive osteoarthropathy Type II collagen mutation: Stickler syndrome

 

 

Sulfate transporter gene mutation: Diastrophic dysplasia Fibrillin gene mutation: Marfanâs syndrome

 

 

Type V collagen mutation: Ehlers-Danlos syndrome Type I collagen mutation: Osteogenesis imperfecta

Correct Answer: Type II collagen mutation

 

 

974. (3716) Q2-7496:

Which of the following is true concerning the genetics of arthritis:

 

1) Siblings have a 27% risk compared to spouses

3) Precocious osteoarthritis is not associated with type V collagen mutation

2) Equal risk in monozygotic twins compared to dizygotic twins

5) Distal interphalangeal joint arthritis is linked to trauma rather than a genetic foci

4) Occurs in all patients with aging hip joints

 

 

One should remember the genetic findings in patients with osteoarthritis: Siblings have a 27% risk compared to spouses

 

 

 

Twice as common in monozygotic twins compared to dizygotic twins Precocious osteoarthritis is associated with type V collagen mutation Does not occur universally in aging hip joints

 

 

Distal interphalangeal joint arthritis linked to a region of chromosome 2q Correct Answer: Siblings have a 27% risk compared to spouses

homeobox-containing gene:

 

1) Achondroplasia

3) Diastrophic dysplasia

2) Turnerâs syndrome

5) Multiple epiphyseal dysplasia

4) Cleidocranial dysplasia

 

There are a set of disorders with a sex-linked inheritance pattern that are most likely caused by a point mutation in the short stature homeobox gene. These disorders include:

 

Turnerâs syndrome

 

 

Langer mesomelic dysplasia Leri-Weill dyschondrosteosis

 

The other responses refer to common disorders with well-documented genetic abnormalities: Achondroplasia: FGFR3

 

 

Diastrophic dysplasia: DTDST (sulfate transporter gene) Cleidocranial dysplasia: CBFA1

 

 

Multiple epiphyseal dysplasia: COMP Correct Answer: Turnerâs syndrome

 

976. (3718) Q2-7498:

A mutation in which of the following genes causes a disturbance in normal limb outgrowth patterning:

 

1) CBFA1

3) COL1A1

2) COMP

5) VDR3

4) P63

 

 

P63 is an important factor in normal limb outgrowth patterning. The other factors are involved with common disorders: CBFA1: Cleidocranial dysplasia

 

COMP: Multiple epiphyseal dysplasia

 

 

COL1A1: Osteogenesis imperfecta (easy to remember type I collagen) VDR3: Osteoporosis (easy to remember vitamin D receptor)

Correct Answer: P63

 

 

 

1) No difference in subsequent osteoporotic fractures

3) Reduction in nonvertebral fractures; no reduction in vertebral fractures

2) Reduction in vertebral fractures; no reduction in nonvertebral fractures

5) Equal death rate in the study and control groups

4) Reduction in vertebral and nonvertebral fractures

 

A large prospective, randomized study showed a reduction in vertebral and nonvertebral fractures when patients were treated with intravenous (IV) zoledronic acid within 90 days of a hip fracture, followed up with annual treatment.

Important points to remember about this study:

 

 

Study: Zoledronic acid (5 mg, IV) within 90 days of hip fracture and then annually (1,000 patients in each group) New fractures: 8.6% vs 13.9% (absolute risk reduction, 5.3%; relative risk reduction, 35%)

 

New fractures

 

  o   Vertebral: 1.7% vs 3.8% (P = .02)

  o   Nonvertebral: 7.6% vs 10.7% (P = .03)

 

  o   Hip: 2.0% vs 3.5% (relative risk 30%, not significant)   o   Divergence of fracture-free survival at 12 months BMD

 

 

  o   12 month: 2.6% vs -1.0%   o   24 month: 4.7% vs -0.7%   o   36 month: 5.5% vs -0.9% Death

 

 

  o   Hazard ratio: -0.72 (0.56 to 0.93 CI, P = .01) Adverse advents

 

  o   Pyrexia: 8.7% vs 3.1%   o   Myalgia: 4.9% vs 2.7%

  o   Bone pain: 3.2% vs 1.0%

Correct Answer: Reduction in vertebral and nonvertebral fractures

 

 

 

1) Decrease in new fractures; no improvement in bone mineral density (BMD)

3) No difference in new fractures; no difference in survival

2) No difference in new fractures; no improvement in BMD

5) No difference in fracture-free survival; no difference in vertebral fractures

4) Decrease in new fractures; survival advantage

 

A large prospective, randomized study showed a reduction in vertebral and nonvertebral fractures when patients were treated with intravenous (IV) zoledronic acid within 90 days of a hip fracture, followed up with annual treatment.

Important points to remember about this study:

 

 

Study: Zoledronic acid (5 mg, IV) within 90 days of hip fracture and then annually (1,000 patients in each group) New fractures: 8.6% vs 13.9% (absolute risk reduction, 5.3%; relative risk reduction, 35%)

 

New fractures

 

  o   Vertebral: 1.7% vs 3.8% (P = .02)

  o   Nonvertebral: 7.6% vs 10.7% (P = .03)

 

  o   Hip: 2.0% vs 3.5% (relative risk 30%, not significant)   o   Divergence of fracture-free survival at 12 months BMD

 

 

  o   12 month: 2.6% vs -1.0%   o   24 month: 4.7% vs -0.7%   o   36 month: 5.5% vs -0.9% Death

 

 

  o   Hazard ratio: -0.72 (0.56 to 0.93 CI, P = .01) Adverse advents

 

  o   Pyrexia: 8.7% vs 3.1%   o   Myalgia: 4.9% vs 2.7%

  o   Bone pain: 3.2% vs 1.0%

Correct Answer: Decrease in new fractures; survival advantage

 

 

 

1) Decreased vertebral fractures, no difference in nonvertebral fracture, and no difference in survival

3) No difference in vertebral and nonvertebral fracture and no difference in survival

2) Decreased vertebral fractures, decreased nonvertebral fracture, and improved survival

5) Decreased fracture rate but no difference in survival or BMD

4) Improved bone mineral density (BMD) but no difference in fracture rate

 

A large prospective, randomized study showed a reduction in vertebral and nonvertebral fractures when patients were treated with intravenous (IV) zoledronic acid within 90 days of a hip fracture, followed up with annual treatment.

Important points to remember about this study:

 

 

Study: Zoledronic acid (5 mg, IV) within 90 days of hip fracture and then annually (1,000 patients in each group) New fractures: 8.6% vs 13.9% (absolute risk reduction, 5.3%; relative risk reduction, 35%)

 

New fractures

 

  o   Vertebral: 1.7% vs 3.8% (P = .02)

  o   Nonvertebral: 7.6% vs 10.7% (P = .03)

 

  o   Hip: 2.0% vs 3.5% (relative risk 30%, not significant)   o   Divergence of fracture-free survival at 12 months BMD

 

 

  o   12 month: 2.6% vs -1.0%   o   24 month: 4.7% vs -0.7%   o   36 month: 5.5% vs -0.9% Death

 

 

  o   Hazard ratio: -0.72 (0.56 to 0.93 CI, P = .01) Adverse advents

 

  o   Pyrexia: 8.7% vs 3.1%   o   Myalgia: 4.9% vs 2.7%

  o   Bone pain: 3.2% vs 1.0%

Correct Answer: Decreased vertebral fractures, decreased nonvertebral fracture, and improved survival

 

 

 

1) Osteonecrosis of the jaw

3) Nausea and vomiting

2) Esophageal irritation and dyspepsia

5) Pruritic rash

4) Pyrexia and myalgia

 

A large prospective, randomized study showed a reduction in vertebral and nonvertebral fractures when patients were treated with intravenous (IV) zoledronic acid within 90 days of a hip fracture, followed up with annual treatment.

Important points to remember about this study:

 

 

Study: Zoledronic acid (5 mg, IV) within 90 days of hip fracture and then annually (1,000 patients in each group) New fractures: 8.6% vs 13.9% (absolute risk reduction, 5.3%; relative risk reduction, 35%)

 

New fractures

 

  o   Vertebral: 1.7% vs 3.8% (P = .02)

  o   Nonvertebral: 7.6% vs 10.7% (P = .03)

 

  o   Hip: 2.0% vs 3.5% (relative risk 30%, not significant)   o   Divergence of fracture-free survival at 12 months BMD

 

 

  o   12 month: 2.6% vs -1.0%   o   24 month: 4.7% vs -0.7%   o   36 month: 5.5% vs -0.9% Death

 

 

  o   Hazard ratio: -0.72 (0.56 to 0.93 CI, P = .01) Adverse advents

 

  o   Pyrexia: 8.7% vs 3.1%   o   Myalgia: 4.9% vs 2.7%

 

  o   Bone pain: 3.2% vs 1.0% Correct Answer: Pyrexia and myalgia

 

981. (3723) Q2-7503:

A 65-year-old woman sustains a hip fracture following a minor fall. Which of the following treatments should be considered:

 

1) A. Hormone replacement therapy

3) Antiresorptive therapy

2) Intermittent parathyroid hormone therapy

5) Calcium and vitamin D supplementation and repeat bone mineral density measurement in 1 year

4) Prophylactic fixation of the contralateral hip

 

This patient has a new fracture. Because the fracture occurred following minor trauma, the physician should assume that this patient has an insufficiency fracture related to her osteoporosis.

Patients who sustain an osteoporotic hip fracture should be treated with antiresorptive therapy to lower the risk of a subsequent hip or vertebral fracture. A recent randomized trial showed the following:

A large prospective, randomized study showed a reduction in vertebral and nonvertebral fractures when patients were treated with intravenous (IV) zoledronic acid within 90 days of a hip fracture, followed up with annual treatment.

Important points to remember about this study:

 

 

Study: Zoledronic acid (5 mg, IV) within 90 days of hip fracture and then annually (1,000 patients in each group) New fractures: 8.6% vs 13.9% (absolute risk reduction, 5.3%; relative risk reduction, 35%)

 

New fractures

 

  o   Vertebral: 1.7% vs 3.8% (P = .02)

  o   Nonvertebral: 7.6% vs 10.7% (P = .03)

  o   Hip: 2.0% vs 3.5% (relative risk 30%, not significant)   o   Divergence of fracture-free survival at 12 months

Correct Answer: Antiresorptive therapy

 

982. (3768) Q2-7550:

Which of the following biomaterials is considered inert:

 

1) Porous tantalum

3) Biodegradable polymeric scaffolds

2) Autologous chondrocytes

5) Cobalt-chromium alloys

4) Calcium sulfate pellets

 

Biocompatibility refers to materials that can be implanted into the body without causing major adverse reactions. Some materials, such as cobalt chromium alloys, are essentially inert; these materials cause no reaction from the body.

 

Other materials might be biocompatible, but they are not inert: Porous tantalum is a metal material that grows into bone.

 

 

Autologous chondrocytes are grown in vitro and then used as filler for cartilage defects. Biodegradable polymeric scaffolds are resorbed and new tissues are laid down upon them.

 

Calcium sulfate pellets are quickly resorbed over a 4- to 6-week period and new bone formation occurs either completely or incompletely.

Correct Answer: Cobalt-chromium alloys

 

 

983. (3769) Q2-7551:

Which of the following materials is biocompatible in bulk form but may cause severe soft tissue reactions and damage in particulate form:

 

1) Freeze-dried allograft

3) Polymethylmethacrylate

2) Fresh-frozen allograft

5) Cobalt-chromium alloy

4) Ultra-high molecular weight polyethylene

 

Ultra-high molecular weight polyethylene is inert in bulk form but may cause severe bone loss when found in a particulate form. Wear debris that is generated at a polyethylene metal articulation is ingested by macrophages and an inflammatory response is generated. Bone resorption often results with aseptic loosening of the involved component.

 

Correct Answer: Ultra-high molecular weight polyethylene

 

 

 

1) Between the femoral head and tapered neck

3) Delamination of high-density polyethylene

2) Screw head and countersunk region of the acetabular component

5) Irradiation of high-density polyethylene in an ambient environment

4) At the interface between a plate and the screw heads

 

Galvanic corrosion is caused by an electrochemical potential that is created between two metals that are located in a conductive environment, such as body fluids.

 

Examples of galvanic corrosion include: Screw heads and a plate

 

 

Femoral head screw and barrel of a dynamic hip screw Interlocking screws and an intramedullary nail

Galvanic corrosion can also occur within a metal if there are impurities (intergranular corrosion). The other responses refer to:

 

Fretting corrosion: Between the femoral head and tapered neck

 

 

Crevice corrosion: Screw head and countersunk region of the acetabular component Oxidative degradation: Delamination of high-density polyethylene

 

 

Oxidative degradation: Irradiation of high-density polytheylene in an ambient environment Correct Answer: At the interface between a plate and the screw heads

 

985. (3771) Q2-7553:

Which of the following describes fretting corrosion:

 

1) Impurities within a metal implant

3) At sites of electrochemical gradients

2) At a surface defect of an implant

5) Free-radical generation during sterilization

4) Relative micromotion under load

 

Fretting corrosion occurs when micromotion exists between two metals in contact. One of the most common examples of fretting corrosion is micromotion between a modular femoral head and the tapered neck junction. Modular components, such as the S-ROM system (DePuy Orthopaedics Inc., Warsaw, Ind), are subject to fretting corrosion at each of the junctions.

 

Techniques to minimize fretting corrosion include:

 

Making sure the head-neck junctions are dry and clean

 

Eliminating micromotion but having an exact fit (ie, not mixing manufacturers) The other responses refer to:

 

 

 

Galvanic corrosion: Impurities within a metal implant Crevice corrosion: At a surface defect of an implant Galvanic corrosion: At sites of electrochemical gradients

 

 

Oxidative degradation: Irradiation of high-density polyethylene in an ambient environment Correct Answer: Relative micromotion under load

 

 

1) Impurities within an implant

3) Relative micromotion under load

2) At sites of an electrochemical potential

5) Differences in oxygen tension causing pH and electrolyte changes

4) Free-radical generation during air sterilization

 

Crevice corrosion occurs at the sites of a surface defect in a metal implant. At these defects, changes in pH and electrolyte concentrations cause corrosion.

Common examples of crevice corrosion include:

 

At the interface between an uncemented acetabular component and the cancellous screws (at the contact point where the head of the screw is countersunk into the acetabular shell)

 

At the interface between a screw head and the plate at the point where the screw head contacts the plate The other responses refer to:

 

 

 

Galvanic corrosion: Impurities within a metal implant Galvanic corrosion: At sites of electrochemical gradients Fretting corrosion: Relative micromotion under load

 

 

Oxidative degradation: Free-radical generation during air sterilization Correct Answer: Differences in oxygen tension causing pH and electrolyte changes

 

987. (3773) Q2-7555:

Which of the following has led to oxidative degradation of ultra-high molecular weight polyethylene (UHMWPE):

 

1) Ram extrusion

3) Sterilization in an ambient environment

2) Compression molding

5) Sterilization with ethylene oxide

4) Direct molding

 

One of the most important examples of corrosion is the breakdown of ultra-high density polyethylene. Wear particles result in osteolysis and bone loss. When UHMWPE is sterilized in air, free radicals are generated and lead to oxidative degradation of the UHMWPE.

 

The other responses refer to:

 

 

 

 

Ram extrusion: Manufacturing method for UHMWPE Compression molding: Manufacturing method for UHMWPE Direct molding: Manufacturing method for UHMWPE Sterilization with ethylene oxide: Alternative

 

Correct Answer: Sterilization in an ambient environment

 

 

 

1) Track teams have the highest incidence of stress fractures.

3) Stress fractures occur in normal bone subjected to abnormal stresses.

2) In military recruits, rates of stress fractures are gender dependent.

5) Stress fractures occur in normal bone subjected to normal stresses.

4) Stress fractures occur in sites of bone resorption due to continued loading.

 

The following are features of stress fractures:

1. Stress fractures most often occur from changes in an athleteâs training program.

   1. Increases in intensity

   2. Increases in duration

       

2. In military recruits, the rates are gender dependent.

   1. Men â 4%

   2. Women â 7%

       

3. Stress fractures occur in normal bone subjected to abnormal stresses.

    

4. Stress fractures occur in sites of bone resorption subjected to continued loading.

    

5. Important to know is the definition of insufficiency fractures â fractures in abnormal bone from normal stresses.

 

Correct Answer: Stress fractures occur in normal bone subjected to normal stresses. 989. (3780) Q2-7562:

Which of the following is a significant risk factor for a stress fracture:

 

1) Testosterone levels in men

3) Training surfaces

2) Age

5) Low calcium intake

4) Menstrual irregularity

 

There are a number of risk factors for stress factors:

1. Menstrual irregularity in women is perhaps the most significant risk factor.

   1. Remember the terrible triad in female patients:

      1. Menstrual irregularity

      2. Eating disorders

      3. Low bone mass

          

2. Increase in frequency and intensity of athletic training or activity

    

3. Changes in athletic training are noted in 80% of athletes surveyed who have stress fractures.

    

4. Decreased tibial width (smaller bone size)

    

5. Factors that have not been found to be statistically significant include:

   1. Testosterone levels in male athletes

   2. Age

      1. Location by age is significant, but not etiology

   3. Training surfaces

   4. Flexibility

       

   5. Low calcium intake Correct Answer: Menstrual irregularity

 

 

1) Flexibility

3) Increase in frequency and intensity of training

2) Training surfaces

5) Testosterone levels in athletes

4) Low calcium intake

 

There are a number of risk factors for stress fractures:

1. Menstrual irregularity in women is perhaps the most significant risk factor.

   1. Remember the terrible triad in female patients:

      1. Menstrual irregularity

      2. Eating disorders

      3. Low bone mass

          

2. Increase in frequency and intensity of athletic training or activity

    

3. Changes in athletic training are noted in 80% of athletes surveyed who have stress fractures.

    

4. Decreased tibial width (smaller bone size)

    

5. Factors that have not been found to be statistically significant include:

   1. Testosterone levels in male athletes

   2. Age

      1. Location by age is significant, but not etiology

   3. Training surfaces

   4. Flexibility

   5. Low calcium intake

 

Correct Answer: Increase in frequency and intensity of training 991. (3782) Q2-7564:

Which of the following statements regarding plain radiographic findings of stress fractures is false:

 

1) Plain radiographs have a low false-negative rate.

3) Only 20% of bone scan positive foci correlate with positive radiographic findings.

2) Periosteal bone formation is a hallmark finding.

5) he âgray cortexâ may occur secondary to cortical resorption.

4) Positive radiographic findings include horizontal or linear patterns of sclerosis.

 

Plain radiographs have a high false-negative rate especially early in the clinical course of stress fracture.

 

Periosteal new bone formation is a hallmark finding.

 

 

Only 20% of bone scan positive foci correlate with positive radiographs. Positive radiographic findings include horizontal or linear patterns of sclerosis.

 

The âgray cortexâ may occur from increased osteoclastic resorption on the cortex.

Correct Answer: Plain radiographs have a low false-negative rate.

 

likely to correlate with the bone scan are:

 

1) Periosteal high signal on T2; normal marrow signal on T1- and T2-weighted images

3) Periosteal high signal on T2; increased signal on T1; and normal signal on T2-weighted images

2) Normal periosteal signal; normal marrow signal on T1- and T2-weighted images

5) Normal periosteal signal; decreased marrow signal on T1; and high signal on T2-weighted images

4) Periosteal high signal on T2; normal signal on T1; and high signal on T2-weighted images

 

In 1995, Fredrickson and colleagues classified stress fractures into four grades based upon bone scans: Grade 1Â Â Â Â Â Small ill-defined cortical area of mildly increased activity

Grade 2     Well-defined cortical area of moderately increased cortical activity Grade 3     Wide, cortical-medullary area of increased activity

Grade 4Â Â Â Â Â Transcortical area of intensely increased activity

In an early stress fracture (grade 1 bone scan criteria), a periosteal high signal on T2-weighted images and a normal marrow signal are present.Correct Answer: Periosteal high signal on T2; normal marrow signal on T1- and T2-weighted images

 

 

1. (3784) Q2-7566:

   A patient with stress fracture has a transcortical area of intense uptake on the technetium bone scan. Which of the following findings would most likely be present on the magnetic resonance imaging (MRI) scan:

    

   1) Normal periosteal signal; normal marrow signal on T1; high marrow signal on T2

   3) Normal periosteal signal on T2; low marrow signal on T1; high marrow signal on T2

   2) Normal periosteal signal; low marrow signal on T1; high marrow signal on T2

   5) High periosteal signal on T2; low marrow signal on T1; normal marrow signal on T2

   4) High periosteal signal on T2; low marrow signal on T1; high marrow signal on T2

    

   In 1995, Fredrickson and colleagues classified stress fractures into four grades based upon bone scans: Grade 1Â Â Â Â Â Small ill-defined cortical area of mildly increased activity

   Grade 2     Well-defined cortical area of moderately increased cortical                     activity

   Grade 3Â Â Â Â Â Wide, cortical-medullary area of increased activity Grade 4Â Â Â Â Â Transcortical area of intensely increased activity

    

   In a grade 4 stress fracture, the corresponding MRI will show: High periosteal signal on T2-weighted images

    

    

   Low signal on T1-weighted images, often with a liner low signal line representing the fracture line High signal on T2-weighted images, often with a liner low signal line representing the fracture line

   Correct Answer: High periosteal signal on T2; low marrow signal on T1; high marrow signal on T2

    

    

2. (3785) Q2-7567:

   A patient has a defined area of moderately increased activity in the femoral shaft consistent with a stress fracture (grade 2 by bone scan criteria). Which of the following is the corresponding finding on the magnetic resonance imaging scan:

    

   1) Normal periosteal signal; normal marrow T1 signal; high marrow T2 signal

   3) High periosteal signal; high marrow T1 signal; normal marrow T2 signal

   2) Normal periosteal signal; high marrow T1 signal; high marrow T2 signal

   5) High periosteal signal; normal marrow T1 signal; high marrow T2 signal

   4) High periosteal signal; normal marrow T1 signal; high marrow T2 signal

    

   In 1995, Fredrickson and colleagues classified stress fractures into four grades based upon bone scans: Grade 1Â Â Â Â Â Small ill-defined cortical area of mildly increased activity

   Grade 2     Well-defined cortical area of moderately increased cortical                     activity

   Grade 3Â Â Â Â Â Wide, cortical-medullary area of increased activity Grade 4Â Â Â Â Â Transcortical area of intensely increased activity

   Correct Answer: High periosteal signal; normal marrow T1 signal; high marrow T2 signal

    

    

3. (3786) Q2-7568:

   Which of the following treatment methods is used for the majority of patients with a stress fracture:

    

   1) Rest and protected weight-bearing

   3) Plate fixation with bone grafting

   2) Rest and electrical stimulation

   5) Intramedullary rod fixation

   4) Plate fixation without bone grafting

    

   The majority of stress fractures are treated with rest and protected weight-bearing. When the patient rests, strain on the affected bone is reduced and formation exceeds resorption, leading to bone healing.

   Electrical stimulation and ultrasound have not been shown to increase the rate of healing. For most stress fractures, surgery is not necessary.

   Correct Answer: Rest and protected weight-bearing

    

    

4. (3787) Q2-7569:

   Which of the following stress fractures most often requires internal fixation:

    

   1) Second metatarsal

   3) Sacrum

   2) Femoral shaft

   5) Tension-sided femoral neck

   4) Compression-sided femoral neck

    

   The majority of stress fractures are treated with rest and protected weight-bearing. When the patient rests, strain on the affected bone is reduced and formation exceeds resorption, leading to bone healing.

    

   A tension-sided femoral neck stress fracture is most at risk for progression to a complete fracture and displacement. Correct Answer: Tension-sided femoral neck

    

5. (3788) Q2-7570:

   Which of the following stress fractures is the most prone to nonunion and require surgical intervention:

    

   1) Proximal posteromedial compression

   3) Anterior tibial cortex tension

   2) Distal posteromedial compression

   5) Medial malleolus

   4) Femoral shaft compression

    

   The majority of stress fractures are treated with rest and protected weight-bearing. When the patient rests, strain on the affected bone is reduced and formation exceeds resorption, leading to bone healing.

   An anterior tibial tension stress fracture is most prone to not healing. This fracture typically occurs in the anterior cortex and appears as a horizontal lucency â the dreaded black line.

    

   Many patients with this fracture will not heal nonoperatively and will require intramedullary rod fixation. Correct Answer: Anterior tibial cortex tension

6. (3789) Q2-7571:

   Which of the following activities predisposes a patient to an anterior tibial cortex stress fracture:

    

   1) Long-distance running

   3) Military recruits following long marches

   2) Repetitive jumping or leaping

   5) Playing tennis

   4) Gymnastics

    

    

   Repetitive stresses from jumping or leaping is a risk factor for anterior tibial cortex stress fractures. Correct Answer: Repetitive jumping or leaping

    

7. (3794) Q2-7577:

Which of the following properties is false concerning articular cartilage:

 

1) Avascular (no blood vessels)

3) Alymphatic (no lymphatic vessels)

2) Aneural (no nerve fibers)

5) Self-renewing (maintenance and restoration of extracellular matrix)

4) Moderate friction on cartilage-on-cartilage motion Important properties of articular cartilage include:

 

Avascular (no blood vessels)

 

 

Aneural (no nerve fibers) Alymphatic (no lymphatic vessels)

 

Very low friction on cartilage on cartilage motion

 

 

Self-renewing (maintenance and restoration of extracellular matrix) With aging, loss of ability to maintain the extracellular matrix

Correct Answer: Moderate friction on cartilage-on-cartilage motion

 

 

1000. (3795) Q2-7578:

Which of the following statements is true concerning chondrocytes:

 

1) Chondrocytes represent 10% to 15% of the cartilage volume.

3) Chondrocytes form an intricate network of cell-to-cell contact within the extracellular matrix.

2) Chondrocytes lack an endoplasmic reticulum and Golgi apparatus.

5) Chondrocytes respond to growth factors and anabolic stimuli.

4) Chondrocytes do not decrease their synthetic ability with aging.

 

 

There are several important points to remember about chondrocytes: By cartilage volume, the cells only represent about 1%.

 

Chondrocytes are synthetic machines producing the extracellular matrix.

 

Intracellular organelles

 

 

Endoplasmic reticulum Golgi apparatus

 

 

Chondrocytes do not have cell-to-cell contact in the extracellular matrix. With aging, chondrocytes lose their synthetic abilities.

 

Chondrocytes respond to a number of stimuli:

 

 

Increase matrix production after sensing degradation of the matrix Sense loads and increase matrix production

 

Respond to growth factors and anabolic stimuli

Correct Answer: Chondrocytes respond to growth factors and anabolic stimuli.

 

Which of the following is the proper sequence (or order) of the classes of macromolecules in articular cartilage in regard to the percentage of dry weight of the components (highest to lowest):

 

1) Collagen, proteoglycans, noncollagenous proteins/glycoproteins

3) Proteoglycans, noncollagenous proteins/glycoproteins, collagen

2) Proteoglycans, collagen, noncollagenous proteins/glycoproteins

5) Noncollagenous proteins/glycoproteins, collagen, proteoglycans

4) Collagen, noncollagenous proteins/glycoproteins, proteoglycans

 

 

Articular cartilage has three principal classes of macromolecules: Collagen – 60%

 

Proteoglycans – 25% to 35%

 

Noncollagenous proteins/glycoproteins – 15% to 20%

Correct Answer: Collagen, proteoglycans, noncollagenous proteins/glycoproteins

 

 

1002. (3797) Q2-7580:

Which of the following articular cartilage collagens form cross-banded fibrils:

 

1) Types VI and X

3) Types II, IX, and XI

2) Types I, III, and V

5) Types II, VI, IX, X, and XI

4) Types II, VI, and X

 

The three articular cartilage collagens that form cross bands are types II, IX, and XI. Of particular note:

 

Type XI binds to type II.

 

 

Type IX binds to the cross-banded fibrils in the superficial layer. Type VI attaches to the matrix around the chondrocytes.

 

Type X is near the calcified layer and is probably involved in mineralization of the calcified layer.

Correct Answer: Types II, IX, and XI

 

 

1003. (3798) Q2-7581:

Which of the following molecules binds with type II collagen and may aid in the stabilization of the type II collagen network in articular cartilage:

 

1) Transforming growth factor beta

3) Biglycan

2) Decorin and fibromodulin

5) Cartilage oligomeric protein (COMP)

4) Anchorin CII

 

Decorin and fibromodulin bind to type II collagen and likely stabilize the type II collagen network. The other responses refer to:

 

Biglycan: Binds with type VI collagen

 

 

Anchorin CII: Helps attach chondrocytes to the collagen fibrils COMP: Binds to chondrocytes

Correct Answer: Decorin and fibromodulin

 

A high collagen concentration and a low proteoglycan concentration is found in which of the following zones of articular cartilage:

 

1) Superficial zone

3) Middle (radial or deep) zone

2) Transitional zone

5) Tidemark zone

4) Calcified cartilage zone

 

 

The superficial zone has a number of important characteristics: Thinnest articular cartilage layer

 

Two layers:

 

Most superficial – fine collagen fibrils (lamina splendens)

 

 

Deep layer – flattened fibroblast-like chondrocytes (parallel to joint surface) Forms a cartilage skin

 

Important chemical properties:

 

 

High collagen and low proteoglycan concentration Fibronectin and water concentrations are highest in this zone

 

Great tensile stiffness and strength

 

 

Seals off the cartilage from the immune system Correct Answer: Superficial zone

 

1005. (3800) Q2-7583:

A high concentration of fibronectin and water is found in which of the following articular cartilage zones:

 

1) Superficial zone

3) Middle (radial or deep) zone

2) Transitional zone

5) Tidemark zone

4) Calcified cartilage zone

 

 

The superficial zone has a number of important characteristics: Thinnest articular cartilage layer

 

Two layers:

 

Most superficial – fine collagen fibrils (lamina splendens)

 

 

Deep layer – flattened fibroblast-like chondrocytes (parallel to joint surface) Forms a cartilage skin

 

Important chemical properties:

 

 

High collagen and low proteoglycan concentration Fibronectin and water concentrations are highest in this zone

 

Great tensile stiffness and strength

 

 

Seals off the cartilage from the immune system Correct Answer: Superficial zone

 

 

1) Superficial zone

3) Middle (radial or deep) zone

2) Transitional zone

5) Tidemark zone

4) Calcified zone

 

 

The superficial zone has a number of important characteristics: Thinnest articular cartilage layer

 

Two layers:

 

Most superficial – fine collagen fibrils (lamina splendens)

 

 

Deep layer – flattened fibroblast-like chondrocytes (parallel to joint surface) Forms a cartilage skin

 

Important chemical properties:

 

 

High collagen and low proteoglycan concentration Fibronectin and water concentrations are highest in this zone

 

Great tensile stiffness and strength

 

 

Seals off the cartilage from the immune system Correct Answer: Superficial zone

 

1007. (3802) Q2-7585:

Which of the following statements is true concerning the transitional zone of articular cartilage:

 

1) Cells are ellipsoid shaped and parallel to the articular surface.

3) The chondrocytes have a high concentration of organelles such as rough endoplasmic reticulum and Golgi apparatus.

2) The extracellular matrix has a high water and a low proteoglycan content.

5) The collagen fibers are perpendicular to the surface and resist shear stresses.

4) The extracellular matrix has the largest diameter collagen fibers and the highest concentration of proteoglycans.

 

The transitional zone lies between the superficial and middle zones of the articular cartilage. The following important points should be remembered:

 

The chondrocytes have a high concentration of synthetic organelles such as rough endoplasmic reticulum and Golgi apparatus.

 

The collagen fibers are larger than in the superficial zone.

 

The proteoglycan concentration is higher than the superficial zone.

Correct Answer: The chondrocytes have a high concentration of organelles such as rough endoplasmic reticulum and Golgi apparatus.

 

 

 

1) Superficial zone

3) Middle (radial or deep) zone

2) Transitional zone

5) Tidemark zone

4) Calcified cartilage zone

 

The chondrocytes in the calcified cartilage zone show the least metabolic activity. In contrast, the chondrocytes of the other areas are very active:

 

Superficial zone

 

Fine collagen fibrils (lamina splendens)

 

 

High collagen and low proteoglycan concentration Fibronectin and water concentrations are highest in this zone

 

Transitional zone

 

The chondrocytes have a high concentration of synthetic organelles such as rough endoplasmic reticulum and Golgi apparatus.

 

The collagen fibers are larger than in the superficial zone.

 

The proteoglycan concentration is higher than the superficial zone.

 

Middle (radial or deep) zone

 

 

Largest diameter collagen fibrils Highest proteoglycan content

Correct Answer: Calcified cartilage zone

 

 

1009. (3804) Q2-7587:

Which of the following molecules causes the expression of matrix metalloproteinases that can degrade the articular cartilage extracellular matrix:

 

1) Insulin-dependent growth factor I

3) Interleukin I

2) Transforming growth factor beta

5) Bone morphogenetic protein 7

4) Bone morphogenetic protein 2

 

Interleukin I has the potential to increase expression of matrix metalloproteinases that can dissolve the extracellular matrix. The other responses are anabolic factors:

 

 

 

 

Insulin-dependent growth factor I Transforming growth factor beta Bone morphogenetic protein 2 Bone morphogenetic protein 7

 

Correct Answer: Interleukin I

 

 

1010. (3805) Q2-7588:

Which of the following resist tensile and shear deformation forces in articular cartilage:

 

1) Biglycan

3) Glycosaminoglycans

2) Type II collagen fibers

5) Tidemark

4) Anchorin II

 

Type II collagen fibers resist tensile and shear deformation forces in the articular cartilage.

 

In contrast, the glycosaminoglycan aggregates resist articular cartilage compression and fluid flow. Correct Answer: Type II collagen fibers

 

 

1) Biglycan

3) Glycosaminoglycan aggregates

2) Type II collagen fibers

5) Tidemark

4) Anchorin II

 

Type II collagen fibers resist tensile and shear deformation forces in the articular cartilage.

 

In contrast, the glycosaminoglycan aggregates resist articular cartilage compression and fluid flow. Correct Answer: Glycosaminoglycan aggregates

 

1012. (3807) Q2-7590:

Which of the following stimulates aggrecan core protein and glycosaminoglycan synthesis:

 

1) Static compression within the physiologic range

3) Cyclic intermittent hydrostatic pressure and compressive strain

2) Chronic compressive loads outside the physiologic range

5) Tumor necrosis factor

4) Interleukin I and matrix metalloproteinases

 

Cyclic compressive loads have the ability to stimulate matrix synthesis â aggrecan core protein and the glycosaminoglycans. The other responses are catabolic toward the cartilage â break the cartilage down:

 

 

Tumor necrosis factor Interleukin I

 

Matrix metalloproteinases

 

 

Chronic compressive loads outside the physiologic range Static compression (eg, putting a patient in a cast)

Correct Answer: Cyclic intermittent hydrostatic pressure and compressive strain

 

 

1013. (3808) Q2-7591:

Which of the following are characteristic of osteoarthritis:

 

1) Synovial proliferation, cysts/erosions on both sides of the joint

3) Asymmetric joint space loss, subchondral sclerosis and cysts, osteophyte formation

2) Synovial proliferation, periarticular osteopenia, symmetric joint space loss

5) Periarticular erosions, preservation of the articular surface

4) Subluxation, bone fragmentation, dissolution of the articular surfaces

 

The characteristic findings in osteoarthritis are:

 

 

 

Asymmetric loss of the joint space Subchondral sclerosis and cysts Osteophyte formation

 

As the cartilage degenerates, progressive bone remodeling occurs. The other responses refer to other synovial proliferative disorders:

 

Pigmented villonodular synovitis: Synovial proliferation, cysts/erosions on both sides of the joint

 

Rheumatoid arthritis: Synovial proliferation with lymphocytic infiltration, periarticular osteopenia, symmetric joint space loss

 

 

Charcot neuropathy: Subluxation, bone fragmentation, dissolution of the articular surfaces Gout: Periarticular erosions, soft tissue masses, preservation of the articular surfaces

Correct Answer: Asymmetric joint space loss, subchondral sclerosis and cysts, osteophyte formation

 

 

 

1) Constant collagen, decreased proteoglycan, constant water

3) Decreased collagen, decreased proteoglycan, decreased water

2) Constant collagen, decreased proteoglycan, increased water

5) Constant collagen, constant proteoglycan, increased water

4) Decreased collagen, decreased proteoglycan, increased water

 

The cause of osteoarthritis is unknown. From a chemical standpoint, one of the earliest findings is a decrease in the proteoglycan and an increase in the water content. One should remember:

 

Constant type II collagen content

 

 

Decreased proteoglycan concentration and decreased chain length Increased water content

The decreased proteoglycan content results in increased permeability of the cartilage. A reduction of the stiffness makes the articular cartilage less able to bear loads.

Correct Answer: Constant collagen, decreased proteoglycan, increased water

 

 

1015. (3810) Q2-7593:

Which of the following is characteristic of the second stage of osteoarthritis:

 

1) Reduction in proteoglycan concentration

3) Formation of type I collagen

2) Decrease in water content

5) Reduction in interleukin I levels

4) Chondrocyte proliferation

 

The cause of osteoarthritis is unknown. From a chemical standpoint, one of the earliest findings is a decrease in the proteoglycan and an increase in the water content. One should remember:

 

Constant type II collagen content

 

 

Decreased proteoglycan concentration and decreased chain length Increased water content

In the second stage, there is a cellular response â chondrocyte proliferation. Clusters of chondrocytes producing new matrix are visible.

In this stage, there is nitric oxide and interleukin I production. These are catabolic factors that increase matrix metalloproteinase activity. Degradative enzymes break down types IX and XI collagen, which may compromise the stability of the type II collagen framework.

 

Correct Answer: Chondrocyte proliferation

 

 

 

1) Increased interleukin I levels

3) Formation of type I collagen

2) Decrease in water content

5) Reduced chondrocyte proliferation and synthesis

4) Increased proteoglycan concentration

 

The cause of osteoarthritis is unknown. From a chemical standpoint, one of the earliest findings is a decrease in the proteoglycan and an increase in the water content. One should remember:

 

Constant type II collagen content

 

 

Decreased proteoglycan concentration and decreased chain length Increased water content

In the second stage, there is a cellular response â chondrocyte proliferation. Clusters of chondrocytes producing new matrix are visible.

In this stage, there is nitric oxide and interleukin I production. These are catabolic factors that increase matrix metalloproteinase activity. Degradative enzymes break down types IX and XI collagen, which may compromise the stability of the type II collagen framework.

 

Correct Answer: Increased interleukin I levels

 

 

1017. (3812) Q2-7595:

Which of the following is characteristic of the second stage of osteoarthritis:

 

1) Decrease in water content

3) Increased nitric oxide production

2) Decreased proteoglycan synthesis

5) Production of type I collagen

4) Reduced matrix metalloproteinase production

 

The cause of osteoarthritis is unknown. From a chemical standpoint, one of the earliest findings is a decrease in the proteoglycan and an increase in the water content. One should remember:

 

Constant type II collagen content

 

 

Decreased proteoglycan concentration and decreased chain length Increased water content

In the second stage, there is a cellular response â chondrocyte proliferation. Clusters of chondrocytes producing new matrix are visible.

In this stage, there is nitric oxide and interleukin I production. These are catabolic factors that increase matrix metalloproteinase activity. Degradative enzymes break down types IX and XI collagen, which may compromise the stability of the type II collagen framework.

 

Correct Answer: Increased nitric oxide production

 

 

1018. (3813) Q2-7596:

Which of the following is characteristic of the third and final stage of osteoarthritis:

 

1) Decreased water content

3) Reduced interleukin I levels

2) Increased proteoglycan content

5) Reduced chondrocyte proliferation and function

4) Reduced nitric oxide levels

 

In the last stage of osteoarthritis, there is reduced chondrocyte proliferation and function, which may be secondary to reduced ability to respond to anabolic factors (down regulation). There may be accumulation of molecules that bind to the anabolic factors (and keep the factors from the chondrocytes) such as decorin and insulin-dependent growth factor binding protein.

 

Correct Answer: Reduced chondrocyte proliferation and function

 

Three years ago, a patient underwent successful resection of a third web space neuroma. She now presents with identical symptoms in the same location. She requests surgery because all attempts at conservative care have failed. Recommended treatment includes:

 

1) Phenol injection

3) Deep transverse metatarsal ligament resection

2) Electrical ablation of the nerve

5) Tarsal tunnel release

4) Resection of a stump neuroma

 

The recurrence rate of a previously resected neuroma is approximately 15%. The deep transverse metatarsal ligament is involved in the pathogenesis of a primary, but not a recurrent, neuroma. None of the present symptoms suggests tarsal tunnel syndrome, although this may exist concurrently with a neuroma. Phenol has ablative neural properties, but it cannot be injected due to the local effect on tissue necrosis.Correct Answer: Resection of a stump neuroma

 

 

 

1020. (301) Q3-416:

A 72-year-old woman presents for treatment of a painful hallux valgus deformity. On examination of the foot, crepitus is present to range of motion of the hallux. Pain upon compression of the joint is also present. The hallux valgus angle is 45° and the intermetatarsal angle is 20°. The recommended surgical procedure is:

 

1) Arthrodesis of the hallux metatarsalphalangeal (MP) joint

3) Distal metatarsal osteotomy and distal soft tissue release

2) Proximal first metatarsal osteotomy and distal soft tissue release

5) Arthrodesis first MP joint and distal soft tissue release (Lapidus procedure)

4) Resection arthroplasty MP joint (Keller procedure)

 

In the presence of metatarsalphalangeal joint arthritis, either resection arthroplasty or arthrodesis is recommended. However, with this degree of intermetatarsal deformity, a resection arthroplasty may lead to a high recurrence rate of hallux valgus deformity.Correct Answer: Arthrodesis of the hallux metatarsalphalangeal (MP) joint

 

 

 

1021. (302) Q3-417:

Resection of the tibial sesamoid may result in which deformity of the hallux:

 

1) Hallux extensus

3) Hallux varus

2) Hallux valgus

5) Supination deformity

4) Cock-up deformity

 

The abductor hallucis muscle attaches to the tibial sesamoid and resection without repair of the abductor and medial capsule may lead to hallux valgus. Hallux varus may occur after resection of the fibular sesamoid, and a cock-up extension hallux deformity occurs after resection of both sesamoids or with a rupture of the volar plate.Correct Answer: Hallux valgus

 

 

 

1022. (303) Q3-418:

Arthrodesis of the ankle in a 34-year-old woman should be performed with the ankle positioned in:

 

1) 10° plantarflexion, neutral rotation

3) Neutral dorsiflexion, 5° valgus

2) 10° dorsiflexion, 5° external rotation

5) 10° plantarflexion, 5° internal rotation

4) 10° plantarflexion, 15° external rotation

 

Although the woman may wish to wear shoes of varying height, there is sufficient plantarflexion occurring through the transverse tarsal joint to permit the wearing of high-heel shoes. Any plantarflexion of the fusion will cause arthritis of the transverse tarsal joint, particularly the talonavicular joint. Dorsiflexion of an ankle arthrodesis is associated with a calcaneus position and heel pain. The ankle should be fused in a similar position for both male and female patients.Correct Answer: Neutral dorsiflexion, 5° valgus

 

 

A 27-year-old male athlete presents with a 2-month history of pain along the posteromedial ankle. Swelling is present posteriomedially. The pain is exacerbated with resisted plantarflexion and inversion of the foot. This condition is likely to be associated with:

 

1) Rheumatoid arthritis

3) Seronegative arthritis

2) Repetitive trauma

5) Stress fracture

4) Gout

 

The presence of posterior tibial tendonitis in a young individual should raise the concern for seronegative arthritis. Although a stress fracture of the medial malleolus may be present, pain is not exacerbated with resisted inversion.Correct Answer: Seronegative arthritis

 

 

 

1024. (305) Q3-420:

A 23-year-old collegiate athlete presents for evaluation of recurrent ankle pain associated with ankle sprains. Upon examination, pain is present along the lateral ankle, an anterior drawer test is negative, and marked instability is apparent with inversion stress of the ankle. Stress radiographs are normal. The most likely cause of the patientâs symptoms is:

 

1) Stress fracture of the navicular bone

3) Recurrent dislocation of peroneal tendons

2) Peroneus brevis tear

5) Subtalar instability

4) Osteochondral lesion of the talus

 

Subtalar instability is not common, although a component of instability may be present in conjunction with ankle instability. If symptoms are suggestive of ankle instability but cannot be verified upon clinical or radiographic examination, then subtalar instability is likely to be present. The clinical diagnosis of subtalar instability is difficult.Correct Answer: Subtalar instability

 

 

 

1025. (306) Q3-421:

A 46-year-old nurse presents for treatment of pain in the heel. The pain has been present for 6 months and increases upon rising from bed and after sedentary periods. The pain is focal and reproduced with pressure over the proximal medial heel. The initial treatment most likely to be associated with relief of symptoms is:

 

1) Semi-rigid orthotic support

3) Achilles tendon stretching exercises

2) Stiff sole shoe with heel wedge

5) Physical therapy modalities

4) Cortisone injection

 

With the exception of physical therapy and a rigid orthotic support, most of the treatment alternatives would be helpful in the initial treatment of plantar fasciitis. Achilles stretching combined with a soft, gel-type heel cushion is consistently the most successful modality.Correct Answer: Achilles tendon stretching exercises

 

 

A 72-year-old man presents for evaluation and treatment of pain and limited motion in his arthritic ankle and subtalar joint. The foot is plantigrade with respect to the leg. Radiographs demonstrate ankle arthritis, an absent joint space, no malalignment of the tibiotalar joint, and a normal subtalar joint. The most reliable surgical procedure consistent with maintaining increased activity and patient function is:

 

1) Total ankle replacement

3) Supramalleolar tibial closing wedge osteotomy

2) Supramalleolar tibial opening wedge osteotomy

5) Ankle arthroscopy

4) Ankle arthrodesis

 

Ankle replacement is a treatment alternative that is widely recommended today, although it is still not as reliable as an ankle arthrodesis in terms of predictability and absence of complications. One must consider the option of arthrodesis and replacement carefully with each patient.Correct Answer: Ankle arthrodesis

 

 

 

1027. (308) Q3-423:

A 37-year-old construction worker presents for evaluation and treatment of a painful stiff foot. He has noticed the stiffness for approximately 12 years, and particularly feels the stiffness when he is working on uneven ground surfaces. Upon clinical and radiographic examination, he is noted to have a calcaneonavicular coalition without any peritalar arthritis. Your recommended treatment is:

 

1) Triple arthrodesis

3) Resection of the coalition

2) Subtalar arthrodesis

5) Calcaneocuboid and talonavicular arthrodesis

4) Calcaneal osteotomy

 

Although arthrodesis has proved reliable with respect to managing tarsal coalition in the adult, resection of a calcaneonavicular coalition should be performed whenever possible. This procedure is preferable to a triple arthrodesis. A subtalar arthrodesis would be applicable as treatment for a middle facet coalition in the adult.Correct Answer: Resection of the coalition

 

 

 

1028. (309) Q3-424:

A 28-year-old male runner presents for treatment of a painful lesion under the first metatarsal head (located more toward the medial aspect of the metatarsophalangeal joint). The lesion is associated with painful callosity to palpation, normal hallux function, and a normal position of the first metatarsal. Attempts to relieve the pressure with orthoses and shoe modifications have not been successful. The ideal treatment is:

 

1) Arthrodesis of the first metatarsophalangeal joint

3) Resection of the tibial sesamoid

2) Dorsal wedge osteotomy of the distal first metatarsal

5) Proximal first metatarsal osteotomy

4) Plantar shaving of the tibial sesamoid

 

Planing or shaving of the sesamoid is a reliable procedure for treatment of a specific focal keratosis beneath the tibial sesamoid. Resection of the tibial sesamoid is a reasonable alternative, although it should be used only for pathology of the sesamoid itself. In this individual, the position of the first metatarsal is normal. Since no plantarflexion is present, an osteotomy is not indicated.Correct Answer: Plantar shaving of the tibial sesamoid

 

 

A 29-year-old football player twisted his foot 1 year ago, and he recalls pain and swelling of the midfoot at the time of the injury. No definitive treatment was provided at that time. Although he returned to athletic activity, he has experienced constant pain and occasional swelling. The pain is present upon passive pronation and abduction of the midfoot, and radiographs demonstrate that there is a 2.5-mm gap between the base of the first and second metatarsal and medial and middle cuneiform. Initial management should include:

 

1) Medial to middle column tarsometatarsal arthrodesis

3) Delayed open reduction and internal fixation

2) Cortisone injection to the midfoot

5) A rigid orthotic support and a stiff-soled shoe

4) Physical therapy modalities aimed at mobilization of the midfoot

 

The patientâs history and clinical findings indicate an injury to the tarsometatarsal joint complex, specifically between the middle and the medial columns. Although surgery may become necessary, initial treatment should consist of support. Physical therapy will worsen foot pain and injection is not indicated.Correct Answer: A rigid orthotic support and a stiff-soled shoe

 

 

 

1030. (311) Q3-426:

A 44-year-old man has a 2-year history of pain in his hallux. The pain is accompanied by limited range of motion, pain on passive dorsiflexion of the hallux, and difficulty with athletic activities. Radiographs demonstrate that the plantar two-thirds of the joint is normal, with osteophytes of the dorsal surface of the joint. He has been unsuccessful with shoe wear modifications, and he requests surgery. The ideal procedure for him would be:

 

1) Resection arthroplasty

3) Osteotomy of the first metatarsal

2) Implant arthroplasty

5) Arthrodesis of the metatarsophalangeal joint

4) Cheilectomy of the hallux

 

Preservation of the joint and maintaining range of motion are important to any active individual. Any procedure, such as resection or implant arthroplasty, is contraindicated in this age group. Arthritis has not progressed to the degree that arthrodesis is necessary.Correct Answer: Cheilectomy of the hallux

 

 

 

1031. (312) Q3-427:

A 32-year-old woman with a history of diabetes presents with a 1-month history of painless swelling in the foot. The foot is swollen, warm, and erythema is present in the midfoot. She has no fever and her blood sugars are normal. Radiographs demonstrate the presence of fracture and dislocation of the tarsometatarsal joint. There are no new periosteal bone formations, and complete dorsal dislocation of the metatarsals on the cuneiforms is noted. The ideal treatment is:

 

1) Open reduction and internal fixation

3) Tarsometatarsal arthrodesis

2) Bedrest, limb elevation, and cast immobilization

5) Weight-bearing total contact cast

4) Midfoot biopsy followed by organism-specific antibiotics

 

If there is a contraindication to performing surgery, nonoperative methods of treatment for an acute Charcot neuroarthropathy may be acceptable. This patientâs midfoot is dislocated and is likely to result in a worsening deformity over time, with ulceration and infection possible. Open reduction with internal fixation has not proven sufficient in patients presenting with the symptoms indicated in the scenario. Arthrodesis is most likely to yield a satisfactory outcome.Correct Answer: Tarsometatarsal arthrodesis

 

 

A 54-year-old woman presents with a 1-year history of medial foot and ankle pain. She does not recall an episode of trauma, and she has had no change in her daily living activities. Her foot is changing shape; it is flatter than the opposite foot. On clinical examination she has a unilateral flatfoot deformity, an inability to perform a single heel rise, and weak inversion strength. The subtalar joint is flexible. Following an initial period of support of the foot, surgery is recommended. The ideal procedure is:

 

1) Subtalar arthrodesis

3) Repair torn spring ligament

2) Triple arthrodesis

5) Flexor digitorum longus transfer with calcaneal osteotomy

4) Posterior tibial tendon repair

 

This patient has a rupture of the posterior tibial tendon. Repair of the tendon will not work because there is a degenerative elongation of the tendon that will not heal. Because the foot is flexible, arthrodesis is not necessary. Flexor digitorum longus transfer with calcaneal osteotomy is a reliable procedure for treatment of Stage II posterior tibial tendon insufficiency.Correct Answer: Flexor digitorum longus transfer with calcaneal osteotomy

 

 

 

1033. (314) Q3-429:

The anatomic structure responsible for the development of an interdigital neuroma is:

 

1) The intermetatarsal bursa

3) The deep transverse metatarsal ligament

2) The interosseous tendon

5) The bifurcation of the lateral plantar nerve

4) The third metatarsal head

 

The deep transverse metatarsal ligament passes between the undersurface of the metatarsal heads and connects the volar plate to the adjacent soft tissue structures. The common digital nerve becomes irritated under the sharp edge of the distal portion of the ligament, resulting in nerve swelling and formation of the neuroma.Correct Answer: The deep transverse metatarsal ligament

 

 

 

1034. (315) Q3-430:

A 14-year-old boy with a painful flatfoot deformity presents for evaluation and treatment. He has had pain of the midfoot associated with thickening, callosity, and shoe wear. Shoe wear modifications, orthoses, and restriction of activity have not been successful. On examination, he has a very flexible flatfoot deformity. The hindfoot and midfoot are passively correctable, the subtalar and transverse tarsal joints are mobile, and callosity is present over the talar head. The recommended treatment is:

 

1) Arthrodesis of the subtalar joint

3) Lateral column lengthening osteotomy through the neck of the calcaneus

2) Triple arthrodesis

5) Resection of the symptomatic accessory navicular bone and advancement of the posterior tibial tendon

4) Medial displacement calcaneal osteotomy with flexor digitorum longus tendon transfer

 

It is unusual for an adolescent to require surgical correction of a flatfoot deformity, however, when the deformity is markedly symptomatic, surgery is a reasonable treatment option. Arthrodesis should not be considered as treatment of the flexible flatfoot in the adolescent. There is no indication of an accessory navicular bone being present. Lateral column lengthening (Evans Procedure) is a reliable procedure in this age group. The most common correction in kids with severe flexible pes planus is a lateral column lengthening. This is because most children, such as in this case, have severe forefoot abduction with significant talo-navicular uncoverage. (The description stated that the patient had a callus under the talar head, which means the talus is protruding beyond the navicular medially.) Medial slide calcaneal osteotomy would only correct the heel valgus, whereas a lateral column lengthening has the potential to correct both heel valgus and forefoot abduction.Correct Answer: Lateral column lengthening osteotomy through the neck of the calcaneus

 

 

A 23-year-old woman with juvenile rheumatoid arthritis presents for treatment of painful forefoot deformity. Painful hallux valgus is present and is associated with dislocation of the lesser metatarsophalangeal joints. The recommended surgical treatment is:

 

1) Bunionectomy, first metatarsal osteotomy, and arthroplasty of the lesser metatarsophalangeal joints

3) Arthrodesis hallux metatarsophalangeal joint and resection of the lesser metatarsal heads

2) Resection arthroplasty (Keller procedure) of the first metatarsophalangeal joint and arthroplasty of the lesser metatarsophalangeal joints

5) Resection of all of the metatarsal heads

4) Bunionectomy, first metatarsal osteotomy, and resection of the lesser metatarsal heads

 

The gold standard surgical treatment for rheumatoid patients with severe forefoot deformities is first metatarsophalangeal fusion with second through fifth metatarsal head resections.Correct Answer: Arthrodesis hallux metatarsophalangeal joint and resection of the lesser metatarsal heads

 

 

 

1036. (317) Q3-432:

The most common complication following triple arthrodesis in the adult patient is:

 

1) Malunion of the arthrodesis

3) Ankle instability

2) Nonunion of the arthrodesis

5) Transverse tarsal arthritis

4) Ankle arthritis

 

Each of the possible answers may occur following triple arthrodesis. In numerous studies, ankle arthritis is the complication most likely to occur regardless of the underlying disease process.Correct Answer: Ankle arthritis

 

 

 

1037. (318) Q3-433:

A pantalar arthrodesis is described as a:

 

1) Subtalar and tibiotalar arthrodesis

3) Ankle and triple arthrodesis

2) Tibiotalocalcaneal arthrodesis

5) Ankle arthrodesis and transverse tarsal arthrodesis

4) Triple arthrodesis and transverse tarsal arthrodesis

 

A pantalar arthrodesis is the combination of an ankle and triple arthrodesis. It should not be confused with an ankle and subtalar arthrodesis (tibiotalocalcaneal).Correct Answer: Ankle and triple arthrodesis

 

 

 

1038. (319) Q3-434:

A 23-year-old woman with a bilateral leg and foot deformity presents for evaluation. She has weakness in the foot and ankle, giving way of the ankle, and difficulty with exercise activities. She mentions that both her brother and uncle have similar problems and deformities with their limbs. On examination, she has a cavovarus foot deformity and muscle weakness. The most likely combination of muscle loss is:

 

1) Anterior tibial and intrinsic muscles

3) Peroneus brevis, anterior tibial, and intrinsic muscles

2) Peroneus longus, peroneus brevis, and intrinsic muscles

5) Peroneus longus, extensor hallucis longus, and intrinsic muscles

4) Posterior tibial, anterior tibial, and peroneus longus muscles

 

By history, this patient has hereditary sensorimotor neuropathy (Charcot-Marie-Tooth disorder). Historically referred to as peroneal muscular atrophy, this condition initially affects the peroneus brevis, followed by the intrinsic and anterior tibial muscles. Other patterns of deformity and muscle loss are occasionally present.Correct Answer: Peroneus brevis, anterior tibial, and intrinsic muscles

 

 

A 63-year-old woman presents for evaluation and treatment of a painful bunion deformity. She has a moderate hallux valgus deformity. Pain and crepitus are present with range of motion of the hallux metatarsophalangeal joint. The hallux valgus deformity measures 25° and the intermetatarsal angle is 14°. The recommended surgical procedure is:

 

1) Distal metatarsal osteotomy

3) Distal soft tissue release and proximal metatarsal osteotomy

2) Proximal metatarsal osteotomy

5) Distal soft tissue release and first metatarsal cuneiform arthrodesis

4) Metatarsophalangeal joint arthrodesis

 

Although resection arthroplasty (Keller procedure) may be a reasonable alternative, arthrodesis of the hallux metatarsophalangeal joint is required in the presence of arthritis. Other alternatives, such as osteotomies, are impractical.Correct Answer: Metatarsophalangeal joint arthrodesis

 

 

 

1040. (321) Q3-436:

The nerve commonly associated with painful heel syndrome is the:

 

1) Medial plantar nerve

3) First branch of the lateral plantar nerve

2) Lateral plantar nerve

5) Deep peroneal nerve

4) Calcaneal nerve

 

The first branch of the lateral plantar nerve (occasionally referred to as the nerve to the abductor digiti quinti) is occasionally involved in pathologic painful heel syndrome and plantar fasciitis.Correct Answer: First branch of the lateral plantar nerve

 

 

 

1041. (322) Q3-437:

A 63-year-old woman with diabetes has had an ulcer under the plantar aspect of the foot for 3 months. The ulcer extends from the inferior aspect of the heel pad toward the midfoot. Nonoperative measures have failed to heal the ulcer. The amputation that is most likely to be successful is a:

 

1) Midfoot amputation with a skin graft

3) Below the knee amputation

2) Symeâs amputation

5) Transverse tarsal amputation

4) Transmetatarsal amputation

 

A foot salvage amputation, including the transarticular ankle amputation (Symeâs amputation), will not work in the presence of a disrupted heel pad (with or without ulceration) and infection of the heel.Correct Answer: Below the knee amputation

 

 

 

1042. (323) Q3-438:

A 56-year-old man has a painful flatfoot deformity. Attempts at orthotic support and bracing of the foot have not been successful. On examination, the forefoot is abducted, the heel is fixed in valgus, and the subtalar joint is rigid. The operation that is most likely to correct the foot deformity is:

 

1) Flexor digitorum longus transfer into the navicular

3) Transverse tarsal arthrodesis

2) Calcaneus osteotomy

5) Lateral column lengthening calcaneus osteotomy

4) Triple arthrodesis

 

By history and physical examination, this patient has a Stage III flatfoot deformity. Due to the rigidity, only an arthrodesis will correct this abnormality. Although a transverse tarsal arthrodesis (Chopartâs arthrodesis) may adequately correct the deformity, a triple arthrodesis will correct all of the components including heel valgus, forefoot abduction, and midfoot pronation.Correct Answer: Triple arthrodesis

 

 

A 54-year-old woman with a 10-year history of diabetes presents for treatment of a non-healing ulcer that has been present under the plantar aspect of her second metatarsal for 9 months. The ulcer is 1.5 cm in diameter, is associated with mild serous drainage, and has shown no radiographic changes. She has normal circulation to the forefoot. The recommended treatment is:

 

1) Osteotomy second metatarsal

3) Shoe wear modification

2) Resection of the second metatarsal head

5) Orthotic shoe support and shoe modification

4) Total contact cast

 

Management of the non-infected plantar neuropathic ulcer is nonoperative, with the exception of refractory recurrent ulceration. In this case, surgery may be indicated. The most reliable means of healing the ulcer is with the use of a total contact cast that permits immediate ambulation and protection for the rest of the foot. Shoe modifications are required following healing of the ulcer but are insufficient as part of the initial treatment program.Correct Answer: Total contact cast

 

 

 

1044. (325) Q3-440:

A patient presents for treatment in your emergency department following an injury that he sustained 4 hours earlier. His foot was run over by a piece of heavy industrial equipment. On examination, he has pain in the foot, a displaced fracture of the second metatarsal, a 3-cm area of severe contusion over the forefoot, and numbness of the dorsal surface of the foot. The next examination that you recommend is:

 

1) Measurement of compartment pressures in the foot

3) Computerized axial tomography of the midfoot

2) Magnetic resonance imaging of the tarsometatarsal joint

5) Laser Doppler flowmetry

4) Doppler evaluation of the foot pulses

 

Because of his history, this patient may have a compartment syndrome of the foot. Although other studies may be relevant as part of his evaluation, a compartment syndrome mandates emergency treatment. Vascular evaluation, including laser Doppler flowmetry is unreliable in diagnosing compartment syndrome. Imaging studies may be performed as part of the surgical work-up, but they are not indicated at this time.Correct Answer: Measurement of compartment pressures in the foot

 

 

 

1045. (326) Q3-441:

A 63-year-old woman presents for treatment of pain and a burning/tingling sensation along the medial aspect of the foot and hallux. She underwent a tarsal tunnel release 12 months ago, but she has not experienced much symptomatic relief. Upon clinical examination, she has a positive percussion test (Tinel sign) along the course of the distal tibial nerve and pain upon pressure of the tarsal canal. There are no other pertinent clinical findings and a magnetic resonance image does not reveal any pathologic lesion. The next course of treatment is:

 

1) Multiple cortisone injections

3) Repeat release of the tarsal tunnel, specifically of the medial plantar nerve

2) Implantation of a peripheral nerve stimulator

5) Nerve desensitization with peripheral nerve stimulation

4) Multiple sessions of physical therapy

 

This patient presents with symptoms of a tarsal tunnel syndrome, specifically involving the medial plantar nerve. Because she did not experience any initial pain relief from her surgery, one may suspect that an inadequate release was initially performed.

Cortisone injection and physical therapy have no role in the management of a recurrent tarsal tunnel syndrome, although desensitization treatments with neuroleptic medication and manual massage are beneficial following surgery. It is important to rule out a sympathetically mediated pain syndrome prior to embarking on repeat surgery.Correct Answer: Repeat release of the tarsal tunnel, specifically of the medial plantar nerve

 

 

 

 

 

 

Slide 1

For 3 years, a 23-year-old female gymnast has experienced recurrent ankle sprains associated with a sense of instability of the hindfoot. Upon examination, a positive anterior drawer test is present and stress radiographs are taken. She has attempted rehabilitation numerous times. She is unable to compete with her current symptoms. The recommended treatment is:

 

1) Reconstruction of subtalar instability with the peroneus brevis tendon

3) Reconstruction of ankle instability with the split peroneus brevis (Evans procedure)

2) Reconstruction of ankle instability with an anatomic repair (Brostrom procedure)

5) Arthroscopic evaluation of ankle joint followed by reconstruction with split peroneus brevis tendon

4) Reconstruction of ankle instability with the split peroneus brevis (Chrisman-Snook procedure)

 

For athletes, particularly those involved in activities that require repetitive proprioceptive and balance activities of the foot and ankle, an anatomic repair (Brostrom procedure) with addition of the extensor retinaculum (Gould modification) is the only procedure that will allow this individual to return to athletic activity. Surgeons must not sacrifice the peroneal tendon, or part thereof, since this may unnecessarily weaken the foot.Correct Answer: Reconstruction of ankle instability with an anatomic repair (Brostrom procedure)

 

 

 

1047. (328) Q3-443:

 

 

 

Figure 1

A 31-year-old recreational soccer player presents for evaluation of chronic ankle pain during physical activity. He reports a severe inversion ankle sprain that occurred 1 year ago and notes that he was treated with cast immobilization. Upon examination, he does not demonstrate laxity of the ankle ligaments and pain is present along the anterior medial ankle. A radiograph is presented. The recommended treatment is:

 

1) Ankle arthrotomy and excision of loose body

3) Retrograde drilling and bone graft

2) Ankle arthrotomy and ankle synovectomy

5) Arthroscopic debridement and drilling

4) Osteochondral autograft procedure

 

This patient has an osteochondral defect of the talus. According to most classification systems, the grade of the defect is not severe. Retrograde drilling of the defect through the sinus tarsi is possible for a posteromedial lesion of the talus for which the cartilage surface is intact. An autogenous osteochondral bone graft is indicated for a severe lesion with bone loss or following failure of previous attempts at arthroscopic drilling. The ideal procedure is arthroscopic debridement and drilling of the subchondral bone.Correct Answer: Arthroscopic debridement and drilling

 

 

 

 

 

 

Figure 1 Figure 2

A 43-year-old woman has had a 2-year history of ankle pain. Her ankle pain is associated with swelling, decreased activities, and limited range of motion. Upon examination, diffuse warmth and swelling of the ankle are noted. Radiographs and a clinical picture are presented. The most likely diagnosis is:

 

1) Rheumatoid arthritis

3) Septic arthritis

2) Gout

5) Pigmented villonodular synovitis (PVNS)

4) Synovial sarcoma

 

Although pigmented villonodular synovitis (PVNS), infection, or gout may cause inflammatory changes on both sides of the ankle joint, the most likely cause of this inflammatory arthropathy is rheumatoid arthritis. Note the cystic changes, the synovial hypertrophy, and the joint inflammation.Correct Answer: Rheumatoid arthritis

 

 

 

1049. (330) Q3-445:

A 25-year-old football player sustained an injury to his ankle 2 months ago. He has ankle pain upon dorsiflexion and external rotation. A radiograph demonstrates widening of the tibiofibular syndesmosis and a 3-mm space between the medial talus and the medial malleolus. The recommended treatment is:

 

1) Open reduction and internal fixation of a high fibula fracture

3) Repair of the high ankle sprain with syndesmosis screw

2) Reconstruction with peroneus brevis followed by aggressive rehabilitation of the ankle

5) Ankle arthroscopy, synovectomy, and repair of the deltoid ligament

1. Arthrodesis of the tibiofibular syndesmosis

    

   It is imperative that any diastasis of the tibiofibular joint is repaired to prevent the late sequelae (e.g., arthritis), particularly in the athlete. Arthroscopy is not sufficient, other than evaluation for additional joint pathology, and syndesmosis arthrodesis would rarely be indicated for this condition. There is no evidence of a high fibula fracture, although this must be a concern and should always be considered.Correct Answer: Repair of the high ankle sprain with syndesmosis screw

    

    

    

   1050. (331) Q3-446:

   A patient presents for surgical treatment of a third web space neuroma. She inquires as to the potential for complications from the procedure. You inform her that the recurrence rate following excision is approximately:

    

   1) 2%

   3) 15%

   2) 5%

2. 35%

4) 25%

 

The reported recurrence rate following excision of a primary interdigital neuroma is approximately 15%. The recurrence rate should always be communicated to the patient preoperatively.Correct Answer: 15%

 

 

While he is working, an industrial worker sustains a puncture wound to the plantar aspect of his foot. He suspects the wound was caused by a sharp protruding nail that penetrated his sneaker. The most likely organism to be responsible for a subsequent infection is:

 

1. Staphylococcus aureus

3) Staphylococcus epidermidis

2) Pseudomonas aeruginosa

5) Enterobacter

4) Streptococcus viridans

 

Although one must be concerned about the possibility of a Pseudomonas infection, the most common organism following puncture injury is staphylococcus aureus. Unless in the setting of diabetes or immune compromise, anaerobic infection rarely occurs.Correct Answer: Staphylococcus aureus

 

 

 

1052. (333) Q3-448:

A 54-year-old woman sustained an injury to her knee 16 months ago. She describes the injury as a dislocation, and she was treated with ligament reconstruction. She has plantarflexion and inversion strength, absent ankle dorsiflexion, and weak eversion. She desires an improvement in the function of the ankle and the ability to comfortably ambulate. The ideal treatment for her is:

 

1) Ankle arthrodesis in a neutral position

3) Neurolysis of the common peroneal nerve

2) Intramembranous transfer of the posterior tibial tendon

5) Dorsal transfer of the peroneus brevis and longus tendons

4) Nerve graft of the common peroneal nerve

 

Following peroneal nerve injury, varying degrees of plantarflexion weakness may be present. In the patient with an intact and strong posterior tibial muscle, an intramembranous transfer to the dorsum of the foot may yield positive results with possible active dorsiflexion. Although neurolysis or nerve graft may be considered for selected patients, it is unlikely to yield a satisfactory result at this time following injury.Correct Answer: Intramembranous transfer of the posterior tibial tendon

 

 

 

1053. (334) Q3-449:

A 61-year-old man has been treated for type I diabetes for 6 years and presents for evaluation and treatment of an ulcer on the plantar aspect of the forefoot. The ulcer has been present for 4 weeks. The ulcer does not appear infected, claw toe deformities are present, and a posterior tibial pulse is palpable. An important screening test for this patient is:

 

1) Doppler ultrasound

3) Combined technetium-indium scan

2) 128-MHz tuning fork examination

5) Transcutaneous oxygen measurements

4) Semmes-Weinstein monofilament testing

 

Although vascular evaluation of all patients with diabetes is important, this patient has a neuropathic plantar ulcer and it is important to assess the extent of neuropathy. The Semmes-Weinstein monofilament is a first-rate screening tool.Correct Answer: Semmes-Weinstein monofilament testing

 

 

The most common complication following medial subtalar dislocation with incarceration of the talus in the extensor brevis muscle is:

 

1) Avascular necrosis talus

3) Tarsal tunnel syndrome

2) Ankle arthritis

5) Peroneal tendonitis

4) Subtalar joint arthritis

 

A medial peritalar dislocation is easy to reduce even when the head of the talus is incarcerated in the extensor brevis muscle. Following reduction, stiffness and arthritis of the subtalar joint occurs. Ankle arthritis and tarsal tunnel syndrome may occur following lateral subtalar dislocation.Correct Answer: Subtalar joint arthritis

 

 

 

1055. (336) Q3-453:

 

 

 

Figure 1

A patient sustained a fracture of the calcaneus 9 months ago. The fracture was treated with non-weight bearing and cast immobilization. The patient experiences constant pain and is unable to work. On examination, he has limited inversion, eversion motion of the foot, and lateral foot pain. Radiographs are presented. The recommended treatment is:

 

1) Physical therapy aimed at increasing subtalar joint motion

3) Triple arthrodesis

2) Nonsteroidal anti-inflammatory medication and orthotic treatment

5) Subtalar arthrodesis

4) Osteotomy of calcaneus and debridement of peroneal tendonitis

 

In the presence of stiffness of the subtalar joint, physical therapy modalities are unlikely to improve the foot function. For the young active worker, an early subtalar arthrodesis is the most reliable procedure to return him to work and an active lifestyle. A triple arthrodesis is contraindicated in the absence of painful transverse tarsal arthritis.Correct Answer: Subtalar arthrodesis

 

 

 

 

 

 

 

Figure 1

A 44-year-old woman presents with chronic pain in the region of the forefoot. She is unable to wear a shoe with a heel and she has pain in the region of the second toe. On examination, she has swelling of the second toe and painful inflammation of the metatarsophalangeal joint. A clinical picture of her foot is presented. Your initial treatment consists of:

 

1) Rigid shoe and a toe splint

3) Semirigid orthotic support

2) Cortisone injection

5) Nonsteroidal anti-inflammatory medication and physical therapy treatments

4) Night splinting of the second toe

 

This patient has idiopathic synovitis of the second metatarsophalangeal (MP) joint. This may be associated with hallux valgus or a long second metatarsal, leading to attritional changes in the volar plate and secondary instability of the MP joint. Immobilization of the toe with limitation of dorsiflexion is required. Although cortisone injection may be effective, toe support must be the initial form of treatment.Correct Answer: Rigid shoe and a toe splint

 

 

 

1057. (338) Q3-455:

The most reliable clinical finding of an acute compartment syndrome of the foot is:

 

1) Absent pulses

3) Diminished sensation along the dorsal foot surface

2) Diminished sensation along the plantar medial foot

5) Pain upon passive dorsiflexion of the toes

4) Marked tense foot swelling and pain

 

The most reliable clinical finding of an acute compartment syndrome of the foot is pain upon passive dorsiflexion of the toes. Decreased sensation does not occur commonly and is a late finding, along with changes in perfusion to the foot.Correct Answer: Pain upon passive dorsiflexion of the toes

 

 

 

1058. (339) Q3-456:

A 9-year-old girl presents for treatment of a calcaneus deformity of the foot that has progressively worsened over the past 3 years. She has a history of poliomyelitis. Upon examination, she has poor plantarflexion, neutral varus and valgus of the hindfoot, and strong dorsiflexion. The preferred treatment for this deformity is:

 

1) Posterior transfer of the posterior tibial tendon to the fibula

3) Posterior transfer of the posterior tibial and peroneal tendons to the calcaneus

2) Posterior transfer of the anterior tibial tendon to the calcaneus

5) Ankle arthrodesis in slight plantarflexion

4) Pantalar arthrodesis

 

A calcaneus deformity is ideally treated with posterior transfer of the anterior tibial tendon to the calcaneus. In the presence of calcaneovalgus deformity (which is not present in this child), posterior transfer to the fibula is a better procedure to prevent continued valgus deformity of the ankle.Correct Answer: Posterior transfer of the anterior tibial tendon to the calcaneus

 

 

 

 

 

 

Figure 1

A 54-year-old woman presents for treatment of leg weakness. She is unable to walk up stairs. She recalls an injury to her ankle while playing tennis 1 year ago. Upon examination, she has poor plantarflexion strength, but excellent dorsiflexion and inversion strength. A magnetic resonance image of her leg is presented. The recommended treatment is:

 

1) Transfer of the flexor hallucis longus muscle to the calcaneus

3) Transfer of the anterior tibial tendon to the distal Achilles tendon

2) Repair of the Achilles tendon

5) Transfer of the posterior tibial and peroneus brevis tendons to the calcaneus

4) Transfer of the anterior tibial tendon to the calcaneus

 

This patient sustained a rupture of the Achilles tendon that went untreated for 1 year. She has symptomatic weak plantarflexion that may be improved by tendon transfer. Achilles repair is not possible due to the size of the defect. Although transfer of the peroneus brevis muscle or the flexor digitorum longus muscle has been described for correction of plantarflexion weakness, the flexor hallucis longus muscle is stronger and a better transfer.Correct Answer: Transfer of the flexor hallucis longus muscle to the calcaneus

 

 

 

1060. (341) Q3-458:

 

 

 

Figure 1

A 19-year-old collegiate lacrosse player presents for treatment of acute pain along the lateral aspect of the foot. The pain developed during a preseason game 1 week ago. A radiograph is presented. The treatment that will return the athlete to playing competitively with the least likelihood of complications is:

 

1) Open reduction and internal fixation

3) Cast immobilization and non-weight bearing

2) Open reduction and bone grafting

5) Percutaneous screw fixation

4) Removable boot immobilization, weight bearing, and pool therapy

 

To rapidly return the competitive athlete to full function, percutaneous screw fixation of an acute fracture or a stress fracture of the fifth metatarsal at the junction of the metaphysis and diaphysis is preferred treatment. Although nonoperative treatment is associated with fracture healing, the limited function and requirement for immobilization, and possibly limited weight bearing, makes this alternative less appealing in the athlete.Correct Answer: Percutaneous screw fixation

 

 

 

 

 

 

Figure 1

A 19-year-old woman presents for treatment of a painful hallux valgus deformity. In addition to the foot deformity, she has spastic hemiplegic cerebral palsy. A clinical picture of her foot is presented. The recommended treatment is:

 

1) Distal metatarsal osteotomy

3) Distal metatarsal and proximal hallux phalangeal osteotomy

2) Proximal metatarsal osteotomy

5) Arthrodesis hallux metatarsophalangeal (MP) joint

4) Tendon transfer of the adductor hallucis to the abductor hallucis

 

In patients with spasticity, arthrodesis of the hallux metatarsophalangeal joint is the only reliable means of controlling the hallux and preventing recurrent deformity.Correct Answer: Arthrodesis hallux metatarsophalangeal (MP) joint

 

 

 

1062. (343) Q3-460:

The most common complication of arthrodesis of the proximal interphalangeal (PIP) joint is:

 

1) Claw toe deformity

3) Hammer toe deformity

2) Mallet toe deformity

5) Instability of metatarsophalangeal (MP) joint

4) Curly toe deformity

 

With arthrodesis of the proximal interphalangeal joint (PIP), the long flexor tendon that remains intact flexes the toe at the metatarsophalangeal (MP) joint and also at the distal interphalangeal (DIP) joint, thus the development of a mallet toe deformity.Correct Answer: Mallet toe deformity

 

 

 

 

 

 

Figure 1

A 59-year-old woman presents for treatment of a painful hallux valgus deformity. She has a prominent bunion, normal motion of the hallux metatarsophalangeal (MP) joint, and painful callosity under the second MP joint. Radiographs of the foot are presented. The recommended treatment is:

 

1) Arthrodesis of the hallux MP joint

3) Soft tissue release and proximal metatarsal osteotomy

2) Soft tissue release and distal metatarsal osteotomy

5) Resection arthroplasty of the hallux MP joint

4) Soft tissue release and arthrodesis metatarsocuneiform joint

 

This patient has probable instability of the metatarsocuneiform joint manifested by the overload phenomenon of the second metatarsal. Although this is not a sufficient indication for performing an arthrodesis of the metatarsocuneiform joint (modified Lapidus procedure), other findings of second metatarsal overload, including thickening of the cortex of the second metatarsal and instability of the first metatatarsocuneiform joint, should be looked for in addition to hypermobility of the first ray.Correct Answer: Soft tissue release and arthrodesis metatarsocuneiform joint

 

 

 

1064. (345) Q3-464:

In surgical correction of the adult acquired flatfoot deformity, a medial translational calcaneal osteotomy is often performed in conjunction with additional soft tissue correction medially. One of the proposed biomechanical effects of the osteotomy associated with improvement in the arch of the foot is:

 

1) Weakening the peroneus brevis tendon

3) Tightening the lateral plantar ligament

2) Tightening the plantar fascia

5) Medial shift of the Achilles tendon

4) Depression of the first metatarsal axis

 

The medial shift of the calcaneus effectively moves the Achilles tendon, thereby increasing the medial torque on the subtalar joint. The valgus deforming force of the Achilles on the heel is neutralized. The plantar fascia is lengthened, not tightened, by the medial shift of the calcaneus.Correct Answer: Medial shift of the Achilles tendon

 

 

One year ago, a patient underwent a triple arthrodesis for management of a severe foot deformity. Although the deformity of her foot is notably improved since the surgery, she has not walked comfortably and the pain is worse than it had been prior to surgery. Upon clinical examination, she is noted to have a fixed supination deformity of the forefoot and callosity under the base of the fifth metatarsal. The recommended management of this problem is:

 

1) Semirigid orthotic shoe support

3) Calcaneal osteotomy

2) Bracing with a dynamic ankle foot orthoses

5) Revision triple arthrodesis

4) Excision of the base of the fifth metatarsal

 

This patient underwent a triple arthrodesis that resulted in malunion as demonstrated by the location of the callosity and the fixed forefoot deformity.

 

 

A calcaneus osteotomy will not correct the midfoot deformity. Nonoperative treatment will not be sufficient in long-term management.

Correct Answer: Revision triple arthrodesis

 

 

1066. (347) Q3-467:

A 28-year-old woman presents for treatment of pain and swelling in the foot. She had twisted her ankle 2 months ago and her initial treatment consisted of limited activity, crutches, and immobilization. Because she has not been able to wean off the crutches, she has pain in the foot radiating to the ankle and distal lateral leg. She has constant pain in the foot and the swelling appears worse than at the time of her injury. Clinically, there are multiple areas of tenderness in the foot and ankle that appear swollen and sensitive to examination. The study that would be most helpful to clarify this diagnosis is:

 

1) Magnetic resonance imaging examination of the ankle

3) Ultrasound examination of the ankle ligaments

2) Weight-bearing radiographs of the ankle and foot

5) Computerized axial tomography scan of the ankle and subtalar joint

4) Technetium bone scan

 

This patient appears to have an acute sympathetically mediated pain syndrome. Previously referred to as reflex sympathetic dystrophy, it is essential to make an early diagnosis and initiate treatment. While a lumbar sympathetic block has both diagnostic and therapeutic value, a bone scan is an excellent imaging study for screening and diagnostic purposes in this patient.Correct Answer: Technetium bone scan

 

 

 

1067. (348) Q3-468:

A 52-year-old man presents for evaluation and treatment of a painful flatfoot deformity. While playing tennis 2 years ago, he felt a tearing sensation in his foot and ankle. Since that time, he notes that the arch of his foot has become progressively flatter.

Upon examination, he has a flatfoot inability to perform a single heel rise and weak inversion strength. He desires to have this deformity corrected. At surgery, the posterior tibial tendon is grossly normal in appearance. The most likely source of his deformity is:

 

1) Rupture of the Achilles tendon

3) Rupture of the plantar fascia

2) Rupture of the peroneus longus tendon

5) Rupture of the inferolateral long plantar ligament

4) Rupture of the spring ligament

 

A rupture of the spring ligament, the talonavicular capsule, or the deltoid ligament should be looked for in the patient with an acquired flatfoot following trauma. Intratendinous tear of the posterior tibial tendon is also possible.Correct Answer: Rupture of the spring ligament

 

 

A 27-year-old man sustained an injury to his foot 2 ½ years ago when a forklift crushed his foot. He sustained a fracture dislocation of the midfoot and was treated with open reduction and internal fixation. His current complaints are burning in the foot associated with numbness over the dorsal foot surface. On examination, he has severe focal sensitivity over the dorsal foot, particularly in the first web space radiating proximally to the ankle. Radiographs demonstrate mild arthritis and anatomic reduction of the tarsometatarsal and midfoot joints. The prognosis for relief of his foot pain at this stage is:

 

1) Excellent with neuroleptic medication and physical therapy

3) Good with treatment for a sympathetically mediated pain syndrome

2) Fair regardless of the treatment provided

5) Good with biofeedback and job modification

4) Excellent following tarsal tunnel release

 

This patient sustained a crush injury to the foot, and although the dislocation was apparently treated with anatomic reduction, he experiences focal neuritis. It is unlikely that he has a sympathetically mediated pain syndrome, although this should always be considered. The outcome, regardless of treatment, must be guarded for this post-traumatic crush syndrome.Correct Answer: Fair regardless of the treatment provided

 

 

 

1069. (350) Q3-472:

A 34-year-old woman presents for treatment of pain in the hallux. She notes pain upon weight bearing and wearing high-heel shoes. Upon examination, the range of motion of the hallux metatarsophalangeal (MP) joint is 10° dorsiflexion and 30° plantarflexion, with pain upon passive dorsiflexion. Radiographs demonstrate osteophytes over the dorsal surface of the metatarsal head, maintenance of the joint space, and a metatarsal declination angle of 10°. The first metatarsal is elevated above the second metatarsal at the level of the metatarsal neck by 4 mm. The ideal procedure to correct this problem and alleviate pain is:

 

1) Plantarflexion osteotomy first metatarsal neck

3) Dorsiflexion osteotomy first metatarsal neck

2) Plantarflexion osteotomy first metatarsal base

5) Arthrodesis hallux MP joint

4) Cheilectomy first metatarsal and dorsiflexion osteotomy hallux proximal phalanx

 

This patient has mild hallux rigidus with a normal alignment of the first metatarsal. The average elevation of the first metatarsal above the second metatarsal at the level of the metatarsal neck is 7.5 mm, thus, 4 mm is within normal limits. Arthrodesis is not indicated for mild rigidus and osteotomy is indicated only for severe elevation of the first metatarsal. Cheilectomy combined with osteotomy of the proximal phalanx (the Moberg osteotomy) is the preferred procedure.Correct Answer: Cheilectomy first metatarsal and dorsiflexion osteotomy hallux proximal phalanx

 

 

 

1070. (351) Q3-473:

A patient experienced a nondisplaced fracture of the medial and middle cuneiforms. His nonoperative treatment consisted of cast immobilization for 2 weeks with no weight bearing permitted, followed by ambulation as tolerated. He presents for treatment 1 week later with severe swelling in the foot, stiffness of the toes, and limited motion of the hindfoot. The fracture of the cuneiforms appears healed. The ideal management of the stiffness and swelling of the foot is:

 

1) Application of an intermittent foot pump compression device

3) Removable stirrup brace and anti-inflammatory medication

2) Continued cast immobilization and weight bearing as tolerated

5) Cast immobilization with frequent changes to monitor swelling

4) Deep friction massage combined with acupuncture treatments

 

Patients who develop swelling of the foot and ankle following trauma and surgery can be effectively treated with application of an intermittent foot pump device. The bladder of the foot pump can be inserted into either a removable boot or cast, or applied to the foot in combination with other methods of rehabilitation. The foot pump is an effective device for decreasing swelling of the foot in association with acute trauma.Correct Answer: Application of an intermittent foot pump compression device

 

A 31-year-old woman presents for treatment of pain in the hallux. She has been experiencing the pain for 2 years. She notes limited motion of the hallux with pain in the joint, particularly when wearing high-heel shoes. She is unable to toe off with running activities. Upon examination, the motion in the hallux metatarsophalangeal (MP) joint is limited in dorsiflexion and radiographs demonstrate mild arthritis of the joint. She requests surgery to correct this disorder. The recommended treatment is:

 

1) Arthrodesis hallux MP joint

3) Plantarflexion osteotomy of the first metatarsal base

2) Plantarflexion osteotomy of the first metatarsal neck

5) Dorsal cheilectomy metatarsal head

4) Dorsiflexion osteotomy of the metatarsal neck

 

Cheilectomy is the ideal treatment for correction of mild hallux rigidus. Although elevation of the first metatarsal rarely occurs (metatarsus primus elevatus) as the cause for hallux rigidus, osteotomy of the metatarsal should not be used as the treatment for correction of hallux rigidus with normal alignment of the first metatarsal.Correct Answer: Dorsal cheilectomy metatarsal head

 

 

1072. (353) Q3-475:

A 17-year-old woman presents for evaluation of a painful hallux valgus deformity. She is unable to wear shoes comfortably, has pain with athletic and daily activities, and notices that the deformity is gradually worsening. Upon clinical examination, she has generalized ligamentous laxity, with motion of the hallux metatarsophalangeal (MP) joint 75° dorsiflexion and 25° plantarflexion. Motion of the first metatarsal is approximately 8° to 10° of combined dorsiflexion and plantarflexion. There is no pain to range of motion of these joints. The hallux valgus angle is 28° and the 1-2 intermetatarsal angle is 12°. The recommended treatment is:

 

1) Arthrodesis of the first metatarsocuneiform joint (Lapidus)

3) Distal metatarsal osteotomy

2) Proximal metatarsal osteotomy

5) Arthrodesis of the hallux MP joint

4) Resection arthroplasty of the MP joint

 

This adolescent has symptomatic hallux valgus, and surgery is warranted. The motion at the metatarsophalangeal and talometatarsal joints is normal, and there is no evidence of hypermobility despite her generalized ligamentous laxity. Therefore, the modified Lapidus procedure is not indicated. With this deformity, a distal metatarsal osteotomy is ideal.Correct Answer: Distal metatarsal osteotomy

 

 

 

1073. (354) Q3-476:

An 82-year-old woman presents for treatment of a painful second toe deformity. The toe is subluxated at the metatarsophalangeal (MP) joint, and a fixed claw toe deformity is present. Despite severe hallux valgus, and the hallux under riding the second toe, the hallux and bunion are not symptomatic. The procedure that will ideally correct this deformity is:

 

1) Resection arthroplasty hallux, MP, and proximal interphalangeal joint (PIP) arthroplasty second toe

3) Proximal metatarsal osteotomy first metatarsal, MP, and PIP arthroplasty second toe

2) Arthrodesis hallux MP joint, MP, and PIP arthroplasty second toe

5) MP and PIP arthroplasty second toe with flexor to extensor tendon transfer

4) Amputation second toe at the MP joint level

 

This elderly patient has a symptomatic second toe deformity only, and surgery to the hallux should be avoided if possible. This is a common clinical problem, and although patients do not readily accept amputation of the toe, it is the preferred procedure because it does not involve reconstruction of the hallux. Correction of the second toe without amputation will not work unless the hallux deformity is addressed.Correct Answer: Amputation second toe at the MP joint level

 

 

 

 

 

 

Figure 1

A 19-year-old woman had previously been treated for hallux valgus deformity with resection of the medial eminence only. She now presents with severe recurrent deformity of the hallux, with pain. There is neither pain nor crepitus upon range of motion of the hallux metatarsophalangeal (MP) joint. The procedure that will successfully correct the deformity of the hallux and the first metatarsal and maintain motion at the MP joint is:

 

1) Distal metatarsal osteotomy

3) Arthrodesis of the first talometatarsal joint (modified Lapidus)

2) Biplanar distal metatarsal osteotomy

5) Double first metatarsal osteotomy

4) Proximal metatarsal osteotomy

 

This patient has recurrent hallux valgus with a marked increase in the distal metatarsal articular angle (DMAA). Correction of this increased DMAA is essential to obtain motion at the metatarsophalangeal joint, and can only be accomplished with a closing wedge type of osteotomy distally. Although a distal biplanar osteotomy may be sufficient, in view of the magnitude of the deformity, a double first metatarsal osteotomy is preferred.Correct Answer: Double first metatarsal osteotomy

 

 

 

1075. (356) Q3-478:

 

 

 

Figure 1

A 63-year-old woman who underwent attempted correction of a hallux valgus deformity 3 years previously presents to the office. She has pain in the hallux from dorsal abutment of the hallux on the shoe. There is no pain in the lesser toes or metatarsals. The recommended procedure to alleviate the irritation of the hallux is:

 

1) Arthrodesis of the hallux metatarsophalangeal (MP) joint

3) Bone block arthrodesis of the hallux MP joint

2) Resection arthroplasty of the MP joint (Keller)

5) Extensor hallucis lengthening

4) Joint replacement of the hallux MP joint

 

This patient had previously undergone resection arthroplasty (Keller) for correction. A common complication of this procedure is a cock-up toe deformity due to insufficiency of the short flexors. This can be corrected with lengthening of the extensor hallucis. If the latter procedure fails, then an arthrodesis can be performed.Correct Answer: Extensor hallucis lengthening

 

 

 

 

 

 

Figure 1 Figure 2

A 66-year-old woman has experienced the gradual onset of a flatfoot deformity over the past 10 years. She notes that the condition is bilateral, although worse on one side. Presented are clinical and radiographic images of her condition. This is associated with pain upon ambulation and difficulty with shoe wear. The most likely cause of this flatfoot deformity is:

 

1) Posterior tibial tendon tear

3) Neuropathy

2) Spring ligament tear

5) Tarsometatarsal arthritis

4) Subtalar arthritis

 

Although posterior tibial tendon insufficiency is a more common cause of adult acquired flatfoot, in this patient the associated clinical and radiographic deformity makes the diagnosis of tarsometatarsal arthritis more likely.Correct Answer: Tarsometatarsal arthritis

 

 

 

1077. (358) Q3-480:

 

 

 

Slide 1 Slide 2

A 66-year-old woman has experienced the gradual onset of a flatfoot deformity over the past 10 years. She notes that the condition is bilateral, although worse on one side. Presented are clinical and radiographic images of her condition. This is associated with pain upon ambulation and difficulty with shoe wear. The most likely cause of this flatfoot deformity is tarsometatarsal arthritis. The initial recommended treatment is:

 

1) Tarsometatarsal arthrodesis

3) Triple arthrodesis

2) Flexor tendon transfer and osteotomy calcaneus

5) Corset type ankle-foot orthosis

4) Orthotic arch supports

 

The initial treatment of idiopathic tarsometatarsal arthritis in the adult is through foot support, shoe modifications, and orthoses. Tarsometatarsal arthrodesis may be required if these treatments fail.Correct Answer: Orthotic arch supports

 

 

Many materials are used in the production of orthotic arch supports. Plastizote is a material commonly used either alone or in combination. The problem with this material is:

 

1) It cannot be used in patients with neuropathy.

3) It is extremely expensive.

2) It is too hard a material for use with arthritis.

5) It softens and loses resilience quickly.

4) It increases sweating in the foot and is not well tolerated.

 

Plastizote is a remarkably forgiving material and accommodates well to the foot shape. It is soft, and it loses resilience or sponginess after 6 months. Therefore, plastizote is commonly used in combination with other materials for orthotic support, particularly for the patient with neuropathy.Correct Answer: It softens and loses resilience quickly.

 

 

 

1079. (360) Q3-482:

 

 

 

Figure 1

A 35-year-old man has experienced ankle pain for 7 years. It is associated with giving way and progressive deformity of the foot. He notices that the foot is rolling inward and is becoming flatter. The cause of his condition is:

 

1) Tarsal coalition

3) Talonavicular arthritis

2) Subtalar arthritis

5) Rupture spring ligament

4) Recurrent ankle sprains

 

This patient presents with ankle instability and progressively worsening flatfoot, with the hindfoot in valgus. Although a rare condition, this is caused by a talonavicular tarsal coalition, with increasing stress on the ankle likely.Correct Answer: Tarsal coalition

 

 

 

 

 

 

Figure 1

A 14-year-old boy presents for treatment of a painful foot, which has been present for 2 years. He has limited his athletic activities. He has similar symptoms in the opposite foot, although not as severe. On clinical examination, the alignment and appearance of the foot are normal; motion of the foot and ankle is good; and some discomfort is present in the sinus tarsi. Standard radiographs, of which the lateral view is presented, include anteroposterior, lateral, and oblique views. Because the diagnosis is unclear, more imaging studies are required. The next study to obtain is:

 

1) External oblique views of the foot

3) Oblique views of the subtalar joint (Broden)

2) Axial views of the subtalar joint (Harris)

5) Inclined views of the talonavicular joint (Canale)

4) Internal oblique views of the midfoot

 

The radiograph demonstrates changes in the subtalar joint suggestive of a middle facet coalition. Note the sclerosis of the joint surface. Although a computed axial tomography scan may be helpful, standard axial views of the subtalar joint (Harris) taken in the plane of the joint are usually diagnostic of tarsal coalition. Motion of the subtalar joint may be normal in the adolescent with a tarsal coalition.Correct Answer: Axial views of the subtalar joint (Harris)

 

 

 

1081. (362) Q3-484:

 

 

 

Figure 1

The radiograph of a 22-year-old woman with ankle pain and instability is presented. She has noted this problem for 10 years, and it appears to be worsening. The opposite ankle is not symptomatic. She has not had any previous treatment for foot or ankle problems. The cause of this ankle deformity is most likely to be associated with which of the following conditions:

 

1) Recurrent ankle instability

3) Subtalar fusion

2) Congenital bimalleolar dysplasia

5) Fibular hemimelic syndrome

4) Talar growth arrest

 

This patient has a ball and socket ankle, which results from limited motion of the hindfoot during early childhood, either from extensive tarsal coalition, premature hindfoot arthrodesis, or trauma. The condition most commonly associated with a ball and socket ankle is a form of hemimelia of the fibula with lateral ray deficiencies and associated tarsal coalition of which the latter is usually extensive.Correct Answer: Fibular hemimelic syndrome

 

 

The sustentaculum tali is the anatomic roof of which tendon:

 

1) Posterior tibial

3) Flexor digitorum brevis

2) Flexor digitorum longus

5) Flexor hallucis longus

4) Anterior tibial

 

The sustentaculum tali forms an arch under which the flexor hallucis longus passes. This is of anatomic significance when resecting middle facet tarsal coalition and performing subtalar arthrodesis.Correct Answer: Flexor hallucis longus

 

 

 

1083. (364) Q3-487:

The nerve most likely to be at risk during surgical exposure when performing a triple arthrodesis is the:

 

1) Sural

3) Intermediate cutaneous branch superficial peroneal

2) Lateral cutaneous branch superficial peroneal

5) Dorsalis pedis

4) Lateral plantar

 

The sural nerve has a variable path in the distal leg, but lies immediately adjacent to the peroneal tendons on the lateral side of the foot. The lateral incision used to expose the subtalar and calcaneocuboid joints is adjacent to this nerve.Correct Answer: Sural

 

 

 

1084. (365) Q3-488:

 

 

 

Slide 1

A 55-year-old man presents for treatment of pain in the Achilles tendon. This has been present for 2 years, but has suddenly become much worse. The pain is approximately 6 cm proximal to the insertion. He is unable to push off during walking and has pain when ascending stairs. Clinical examination reveals thickening of the tendon, weakness of the gastrocnemius-soleus, and pain upon squeezing the Achilles tendon. The magnetic resonance image is shown. The diagnosis is:

 

1) Xanthoma

3) Chronic paratendinitis

2) Degenerative tendinosis

5) Chronic rupture

4) Acute rupture

 

The widening and thickening over a length of the tendon noted clinically and on magnetic resonance image (MRI) is diagnostic of chronic degenerative tendinosis. While paratendinitis may be present simultaneously, limited MRI changes are noted in this condition. Rupture of the tendon may occur and patients with chronic tendinosis should recognize the potential for tendon rupture.Correct Answer: Degenerative tendinosis

 

 

 

 

 

 

Slide 1

A patient presents for surgical correction of a ruptured Achilles tendon. He recalls injuring his ankle 1 year previously, but did not seek any medical treatment at that time. You plan to repair the tendon, and at surgery, a gap between the tendon ends is noted (Slide). The following procedure is not consistent with an acceptable outcome:

 

1) V-Y advancement

3) End-to-end repair with the foot positioned in slight equinus

2) Flexor hallucis tendon transfer

5) Fascial turn down flap from musculotendinous junction

4) Flexor digitorum longus tendon transfer

 

End-to-end repair of a chronic rupture of the Achilles tendon may not be considered if the gap is greater than 2 cm. Equinus positioning is never acceptable. Although each of the other alternatives above may be considered, each has its proponents and potential disadvantages.Correct Answer: End-to-end repair with the foot positioned in slight equinus

 

 

 

1086. (367) Q3-490:

You are commencing a repair of an acute rupture of the Achilles tendon that occurred 8 days previously in a 32-year-old recreational tennis player. Fibrillation of the tendon ends is noted. The following is most important to maximize the ultimate outcome of the repair:

 

1) Resection of the frayed tendon end, and end-to-end apposition

3) Repair of the tendon with the foot in slight equinus

2) Incorporation of the plantaris tendon in the repair

5) Repair with the tendon ends at normal resting tension

4) Augmentation of the repair with a facial turn down flap

 

Repair of the Achilles tendon at its normal resting length is critical. The frayed tendon ends should not be excised, since this will force a repair with the foot in equinus. The resting tension of the repair can be compared with the position of the opposite limb that should be prepared into the operative field.Correct Answer: Repair with the tendon ends at normal resting tension

 

 

 

 

 

 

Slide 1

A 17-year-old patient presents for evaluation and treatment of pain in the back of her ankle. She is a ballet dancer and has noticed that for the past year, she is unable to assume the pointe position without pain. Upon clinical examination she has full range of motion, excellent strength, normal toe function, and pain with pressure in the posterior ankle. The cause of her pain is:

 

1) Flexor hallucis longus tendonitis

3) Anterior tibial tendonitis

2) Osteochondral defect of the talus

5) Os trigonum syndrome

4) Peroneus longus tendonitis

 

Posterior ankle impingement is common in ballet dancers. When in the pointe position, maximum plantar flexion of the ankle is present, and pain may occur from impingement in the posterior ankle. Flexor hallucis tendonitis may cause posterior ankle pain, but there is no evidence for this condition here.Correct Answer: Os trigonum syndrome

 

 

 

1088. (372) Q3-496:

 

 

 

Figure 1

The structure that lies immediately medial to the bone prominence in the posterior ankle shown is the:

 

1) Tibial nerve

3) Peroneus brevis

2) Peroneus longus

5) Flexor hallucis longus

4) Posterior tibiofibular ligament

 

The os trigonum presented in the radiograph may be the cause of posterior ankle impingement. The flexor hallucis longus lies immediately medial to the os and must be protected during excision of this bone.Correct Answer: Flexor hallucis longus

 

 

 

 

 

 

Slide 1

A 43-year-old construction worker sustained a work-related injury to his foot 7 months ago. He was initially treated with cast immobilization and limited weight bearing. He has lateral foot pain and inability to walk comfortably. He has limited walking endurance. Upon examination, pain is present laterally along the course of the peroneal tendons, and no motion of the subtalar joint is present. The recommendation is:

 

1) Physical therapy followed by job modification

3) Nonsteroidal medication, and ankle foot orthoses

2) Shoe modification and orthotic support

5) Subtalar arthrodesis

4) Injection of the peroneal tendons with cortisone

 

A worker who sustains a calcaneus fracture must be returned to the work force as soon as possible. Although these alternatives for treatment may be considered in the patient with limited activity and low demands, the longer the time from injury to salvage surgery with arthrodesis, the less likely it is that the injured worker will ever return to gainful employment. Therefore, subtalar arthrodesis should be performed.Correct Answer: Subtalar arthrodesis

 

 

 

1090. (375) Q3-499:

 

 

 

Slide 1

The structure on the side of the metatarsophalangeal joint of the second toe which is marked by the pointer is the:

 

1) Lumbrical tendon

3) Collateral ligament

2) Volar plate ligament

5) Lateral joint capsule

4) Interosseous tendon

 

The structure is the volar plate ligament. This ligament may assume a pathologic role in claw toe deformity and instability of the metatarsophalangeal joint.Correct Answer: Volar plate ligament

 

 

 

 

 

 

 

Figure 1

A 21-year-old man presents for evaluation of high arches, which have been present his entire life. Currently, he is experiencing some discomfort with running activities. His brother and mother have high arches. He does not recall any trauma as a child, or any other pertinent childhood musculoskeletal problems. Clinical examination reveals a rigid deformity bilaterally. The most common cause for his high arches is:

 

1) Spina bifida

3) Hereditary sensorimotor neuropathy

2) Idiopathic cavovarus

5) Peroneal spastic foot

4) Polio

 

The most common cause of familial cavovarus foot deformity is hereditary sensorimotor neuropathy (Charcot-Marie-Tooth disease). This is an autosomal dominant condition with variable penetrance. Idiopathic cavus foot is common, but not familial, nor is it associated with this extensive deformity.Correct Answer: Hereditary sensorimotor neuropathy

 

 

 

1092. (380) Q3-509:

 

 

 

Figure 1

A 21-year-old man presents for evaluation of high arches, which have been present his entire life. Currently, he is experiencing some discomfort with running activities. His brother and mother have high arches. He does not recall any trauma as a child, or any other pertinent childhood musculoskeletal problems. Clinical examination reveals a rigid deformity bilaterally. What structure is responsible for plantarflexion of the first metatarsal:

 

1) Peroneus longus tendon

3) Plantar fascia

2) Anterior tibial tendon

5) Flexor hallucis brevis

4) Flexor hallucis longus

 

The peroneus longus passes under the cuboid to function as a plantar flexor of the first metatarsal. It is a primary deforming force in the development of the cavus foot.Correct Answer: Peroneus longus tendon

 

 

A 22-year-old patient presents for treatment of a painful foot deformity. On examination, a flexible cavovarus deformity is present. The patient has good dorsiflexion foot strength, and eversion strength is weak. A possible tendon transfer that can be used to correct this deformity is:

 

1) Anterior tibial to middle cuneiform

3) Peroneus longus to peroneus brevis

2) Posterior tibial to peroneus longus

5) Posterior tibial to lateral cuneiform

4) Flexor digitorum to posterior tibial

 

Transfer of the strong peroneus longus to the weak peroneus brevis tendon can be considered to improve function and strength of the cavus foot. Posterior tibial tendon transfer is not indicated because dorsiflexion strength is good. Transfer of the anterior tibial tendon is not indicated, although it is contributing to the midfoot varus.Correct Answer: Peroneus longus to peroneus brevis

 

 

 

1094. (382) Q3-513:

 

 

 

Figure 1 Figure 2

A 56-year-old man presents for treatment of chronic ankle pain. He has noted long-standing pain associated with activities since early adulthood. He does not have any other pertinent musculoskeletal history. Clinical and radiographic examinations reveal ankle arthritis. A probable cause for this arthritis and deformity is:

 

1) Recurrent ankle instability

3) Rheumatoid arthritis

2) Idiopathic osteoarthritis

5) Anterior ankle impingement syndrome

4) Post traumatic arthritis

 

The varus ankle deformity indicates either a chronic hindfoot varus and hindfoot cavus, or chronic recurrent instability of the ankle. If associated with rotatory instability, anterior impingement and eventual arthritis will occur.Correct Answer: Recurrent ankle instability

 

 

 

1095. (383) Q3-515:

When performing fasciotomy of the foot for acute compartment syndrome, the muscle specifically decompressed through medial fasciotomy is:

 

1) Flexor hallucis brevis

3) Extensor hallucis brevis

2) Quadratus plantae

5) First dorsal interosseous

4) Abductor digiti minimi

 

Knowledge of the anatomy and pathophysiology of compartment syndrome of the foot is important to plan adequate and correct treatment. The exact number of compartments is not as relevant as the location and ability to decompress the compartment through fasciotomy. The medial compartment contains the abductor hallucis and the flexor hallucis brevis muscles. The quadratus plantae is more posteriorly located and considered to be in a separate calcaneal compartment.Correct Answer: Flexor hallucis brevis

 

 

This muscle group demonstrates electrical activity at the time of heel strike:

 

1) Anterior compartment

3) Lateral compartment

2) Intrinsic foot muscles

5) Medial compartment

4) Deep posterior compartment

 

The anterior muscle compartment, in particular, the anterior tibialis, is active during heel strike, to maintain foot dorsiflexion, and prevent foot drop during heel strike.Correct Answer: Anterior compartment

 

 

 

1097. (386) Q3-518:

A 7-year-old boy presents with bilateral high arches. His parents report that they are having difficulty finding shoes that comfortably fit him. The patient denies any foot pain. The father had similar problems with his feet and was diagnosed with a âmildâ neurologic condition. On exam, the child has bilateral pes cavus with a supple hindfoot. Treatment of the feet at this time should consist of:

 

1) Soft tissue procedures alone

3) Triple arthrodesis

2) Soft tissue procedures and calcaneal osteotomy

5) Observation

4) Bracing

 

The child has a supple deformity secondary to Charcot-Marie-Tooth disease that will progress if untreated. Soft tissue procedures, which may consist of claw toe correction, plantar release, and possibly tendon transfer, are recommended for children younger than 8 years old who have a supple hindfoot.

 

 

The calcaneal osteotomy is reserved for patients with a rigid hindfoot.

 

Triple arthrodesis is a salvage procedure reserved for a fixed, painful foot in older children.

 

Bracing and observation are not preferred options due to the progressive nature of the disease, and the lack of ability to apply corrective forces to the foot in cavus.

Correct Answer: Soft tissue procedures alone

 

 

1098. (387) Q3-519:

A 50-year-old woman presents with pain in the second toe. She describes this as burning and notes swelling of the toe for the past month. Upon examination, there appears to be instability of the toe with a positive dorsal subluxation stress test. The anatomic structure which is responsible for this patientâs symptoms is:

 

1) The deep transverse metatarsal ligament

3) The medial collateral ligament of the second metatarsophalangeal joint

2) The second common digital nerve

5) The flexor digitorum brevis

4) The plantar plate

 

This patient describes swelling of the toe, which is not associated with an interdigital neuroma. The pain, swelling, and clinical findings suggest a rupture of the plantar plate with early instability and second metatarsophalangeal synovitis.Correct Answer: The plantar plate

 

 

 

 

 

 

Figure 1

A 15-year-old boy presents with a 2-year history of pain in the foot associated with a sense stiffness and of giving way of the ankle. Upon examination, pain in the sinus tarsi, slightly decreased subtalar motion, and normal ankle motion with no apparent instability are noted. A lateral foot radiograph is presented. The next radiograph to obtain is:

 

1) Anteroposterior view of the ankle

3) Axial view of the hindfoot

2) Inversion stress view of the ankle

5) Anteroposterior view of the foot

4) 30° internal oblique view of the foot

 

This child presents with symptoms suggestive of a tarsal coalition. There is stiffness, and symptoms of ankle discomfort or instability. On the lateral radiograph, there is consolidation of trabeculation under the posterior facet in the shape of a âCâ, a typical finding of a middle facet coalition, which should be investigated further with an axial view of the subtalar joint (Harris).Correct Answer: Axial view of the hindfoot

 

 

 

1100. (390) Q3-523:

Which ancillary test is not helpful in the diagnosis of Charcot-Marie-Tooth disease (CMT):

 

1) Electromyography (EMG)

3) Nerve biopsy

2) Nerve conduction velocity (NCV)

5) Muscle enzymes

4) Muscle biopsy

 

Charcot-Marie-Tooth disease (CMT) is a neuropathic process resulting in muscle atrophy, therefore, muscle enzyme studies will not be helpful.

 

Electromyography (EMG) will confirm the diagnosis by displaying increased amplitude and duration of signals, both of which are indicative of a neuropathic process.

 

Nerve conduction velocity (NCV) will also confirm the diagnosis by displaying decreased motor and sensory conduction velocities.

 

 

Nerve biopsy can be helpful by showing loss of myelinated fibers and fibrosis. Muscle biopsy will show diffuse atrophy, fibrosis, and adipose tissue within muscle.

Correct Answer: Muscle enzymes

 

A 67-year-old woman sustained a cerebrovascular accident 18 months previously, and has problems with ambulation. She notes that the ankle buckles with ground contact. Upon examination, she ambulates with slight circumduction of one limb, and heel varus is present during the swing and heel strike phases of gait. The procedure that would stabilize her foot during ground contact is:

 

1) Triple arthrodesis

3) Posterior tibial tendon transfer through the interosseous membrane

2) Subtalar arthrodesis

5) Posterior tibial tendon transfer to the peroneus longus

4) Split anterior tibial tendon transfer

 

A patient with persistent hindfoot varus during ground contact has an overactive anterior tibialis, which will cause a sense of instability upon heel strike. This can be effectively treated with a split anterior tibial tendon transfer, transferring half of the tendon more laterally to the lateral cuneiform or cuboid.Correct Answer: Split anterior tibial tendon transfer

 

 

 

1102. (395) Q3-528:

 

 

 

Figure 1

A 19-year-old man presents for treatment in the emergency department following a motorcycle accident. He sustained an isolated injury to his foot and ankle. The recommended treatment is:

 

1) Primary talonavicular arthrodesis

3) Closed reduction cast immobilization

2) Open reduction internal fixation

5) Closed reduction percutaneous pin fixation

4) Closed reduction external fixation

 

The prognosis following fracture dislocation of the navicular is not good regardless of treatment. Although one may be tempted to perform an open reduction and immediate primary talonavicular arthrodesis, this is not necessary. Following open reduction and internal fixation, arthritis of the talonavicular joint may occur.Correct Answer: Open reduction internal fixation

 

 

 

1103. (397) Q3-530:

A 23-year-old man sustains an injury to his foot when falling off a ladder. The foot is grossly twisted inward, and the talonavicular joint is dislocated with the talar head penetrating through the extensor brevis muscle. The dislocation is reduced. The likelihood of this resulting in avascular necrosis of the talus is:

 

1. Rare

   3) 40%

2. 20%

   5) 100%

   4) 70%

    

   Medial peritalar dislocation does not result in avascular necrosis of the talus. The development of subtalar arthritis is more likely.Correct Answer: Rare

    

    

    

    

    

    

   Figure 1

   A 53-year-old diabetic patient presents with an ulcer on the plantar aspect of the foot that has been present for 2 years. There is mild serous drainage; bone is not exposed. The recommended treatment is:

    

   1. Wound culture, oral antibiotic therapy, and debridement

3. Debridement and split thickness skin grafting

1. Wound culture, intravenous antibiotic therapy, and debridement

5) Debridement and application of a total contact cast

4) Debridement, bone biopsy, and appropriate organism specific antibiotic therapy

 

This is a typical chronic plantar neuropathic ulcer. There is no evidence of acute infection by appearance, and therefore, no cultures or antibiotic therapy is required. Debridement of the ulcer margin only is useful followed by application of a total contact cast. Split thickness skin grafting is never indicated on the plantar foot surface in the setting of neuropathic ulceration.Correct Answer: Debridement and application of a total contact cast

 

 

 

1105. (400) Q3-533:

Which of the following is not a feature of the foot deformity in Charcot-Marie-Tooth disease (CMT):

 

1) Hindfoot valgus

3) Plantarflexed 1st metatarsal

2) Forefoot pronation

5) Interphalangeal (IP) joint flexion

4) Metatarsophalangeal (MTP) joint hyperextension

 

Hindfoot varus develops to counter forefoot pronation due to weakness of evertors with preservation of inverter muscle strength.

 

The first metatarsal plantarflexes relative to the other metatarsals, leading to pronation of the forefoot.

 

 

Plantarflexion of the first metatarsal occurs as part of the windlass mechanism as the intrinsics and plantar fascia contract. As the intrinsics weaken, the toe extensors pull the metatarsophalangeal (MTP) joint into hyperextension as part of the claw toe deformity.

 

When the MTP joint hyperextends, the strength of the long toe flexors pulls the interphalangeal joint into flexion contributing to the claw toe deformity.

Correct Answer: Hindfoot valgus

 

 

 

 

 

Figure 1

A 32-year-old woman was treated surgically for ankle instability 2 years ago. She notes that her ankle is stable, but over the past year, she has noted progressive difficulty with the use of her big toe. She finds that her toe no longer touches the ground. This is confirmed upon pedobarograph testing, because there is no contact between the first metatarsal and the ground, which is an abnormal finding compared to her opposite foot. The appearance of the foot is presented. The probable cause for this is:

 

1) Injury to the flexor hallucis longus

3) Adhesions laterally to the peroneus brevis

2) Turf toe injury

5) Excessive scarring and malfunction of the posterior tibial tendon

4) Use of the peroneus longus in the ankle reconstruction

 

The primary function of the peroneus longus is to depress or plantarflex the first metatarsal and oppose the effect of the anterior tibialis on the base of the first metatarsal. The peroneus longus is no longer functioning, and first metatarsus elevatus is present.Correct Answer: Use of the peroneus longus in the ankle reconstruction

 

 

 

1107. (404) Q3-537:

A 26-year-old woman presents for treatment of painful forefoot deformity. Hallux valgus is present, with a 35° angle, and arthritis of the metatarsophalangeal (MP) joint. The second and third lesser toe MP joints are dislocated with juxta-articular erosions of the fourth metatarsal head noted. The ideal surgical treatment is:

 

1) Silastic joint replacement of the hallux and osteotomy of the lesser metatarsals

3) Arthrodesis of the hallux MP joint and resection of the lesser metatarsal heads

2) Resection arthroplasty of the hallux and silastic arthroplasty of the lesser toe MP joints

5) Resection arthroplasties of all the MP joints

4) Bunionectomy, proximal metatarsal osteotomy, and resection arthroplasty of the lesser MP joints

 

For the patient with rheumatoid arthritis, stabilization of the hallux metatarsophalangeal joint is necessary, and a combination bunionectomy and metatarsal osteotomy is unlikely to succeed in the long-term when arthritis is present. Although shortening osteotomies of the lesser toe metatarsals may be considered to reduce the joint dislocations, this procedure has not yet been reported with long-term follow-up. Silastic joint replacement is not a procedure with long-term benefit, and is not indicated for the lesser toes.Correct Answer: Arthrodesis of the hallux MP joint and resection of the lesser metatarsal heads

 

 

 

1108. (406) Q3-539:

A 20-year-old collegiate football player sustains an injury to his big toe during a scrimmage game. He was pushing off when another player fell on his foot, resulting in the hallux being hyperextended. Two days later he has pain and swelling in the joint, limited motion, and normal radiographs. The recommended treatment is:

 

1) Ultrasound, whirlpool, and joint mobilization

3) Rest, compression, toe taping, and gradual rehabilitation

2) Short leg cast or boot for 4 weeks

5) Active toe exercises and resumption of activities to prevent joint stiffness

4) Joint injection of corticosteroid and lidocaine

 

This is a typical turf toe injury caused by hyperextension of the hallux, and injury to the plantar plate. This injury may result in marked disability if not correctly treated, and the joint must be rested, although cast and boot immobilization is not necessary. Injection is not indicated, and taping of the toe will alleviate pain and permit ambulation.Correct Answer: Rest, compression, toe taping, and gradual rehabilitation

 

 

A 43-year-old patient presents with pain in the hallux metatarsophalangeal (MP) joint. Motion is limited in dorsiflexion and to some extent in plantarflexion, and mild arthritis is radiographically evident. If a cheilectomy is performed on this patient, what is the primary goal of the procedure in the management of hallux rigidus:

 

1) To increase the range of motion of the MP joint

3) To decrease the impingement on the terminal branch of the deep peroneal nerve

2) To remove the osteophytes from the medial and lateral surface of the metatarsal head

5) To decrease the likelihood of a subsequent arthrodesis of the MP joint

4) To decrease pain

 

The goal of cheilectomy is to decrease pain. Although motion may increase, this must not be the goal of surgery because the motion may only be minimally increased. Some patients improve motion markedly after cheilectomy, but this should not be the focus of treatment or promised to the patient.Correct Answer: To decrease pain

 

 

1110. (1392) Q3-1763:

The most common complication after resection of a plantar fibromatosis is:

 

1) A recurrent fibroma

3) Wound dehiscence

2) Infection

5) Injury to the lateral plantar nerve

4) Injury to the medial plantar nerve

 

The most common complication after resection of plantar fibromatosis is recurrence. Although other complications (nerve injury and wound dehiscence) do occur, they occur less frequently. The most reliable treatment for plantar fibromatosis is observation and shoe wear modification if the lesion is painful.Correct Answer: A recurrent fibroma

 

 

1111. (1393) Q3-1764:

A 24-year-old man presents for treatment of a painful fifth toe deformity. He had the deformity for 10 years and notes that it is getting progressively worse. On examination, a claw toe deformity is present. There is 90° of fixed hyperextension of the metatarsophalangeal joint, 70° of flexion at the interphalangeal joint, and a painful corn on the distal tip of the phalanx. The patient would like surgical correction. Which procedure is most likely to give him relief of pain and correction of deformity:

 

1) Flexor tenotomy and extensor tenotomy

3) Proximal interphalangeal (PIP) joint resection arthroplasty

2) Dorsal capsulectomy, extensor lengthening, and flexor tenotomy

5) Subtotal proximal phalangectomy with tendon transfer

4) PIP joint arthrodesis

 

Correction of a fixed claw fifth toe deformity is not an easy procedure. The customary procedures used for correction of other lesser toe deformities are not always successful. In this patient, PIP arthroplasty or arthrodesis alone will not correct this deformity. The deformity requires a subtotal or complete proximal phalangectomy. Although this procedure corrects the deformity, patients must know that they will inevitably have a floppy fifth toe.Correct Answer: Subtotal proximal phalangectomy with tendon transfer

 

 

1112. (1394) Q3-1765:

A 22-year-old collegiate basketball player presents for treatment of a stress fracture of the base of the fifth metatarsal at the junction of the metaphysis and diaphysis. The fracture was treated operatively, and the patient returned to playing basketball. Three months later, it was apparent that a repeat fracture was present. The fracture was treated with screw removal and a repeat screw fixation. Four months later, after a successful basketball season, he sustained a repeat stress fracture of the metatarsal. On examination, he has a mild cavovarus foot configuration with normal ankle range of motion. Inversion is 15° and eversion is 5°. The base of the fifth metatarsal is prominent. The most likely cause for the repeat fracture is:

 

1) Abnormal ankle biomechanics

3) A varus heel

2) Chronic unrecognized ankle instability

5) Chronic avascularity of the fifth metatarsal base

4) Bone sclerosis of the fifth metatarsal base

 

The most common cause of recurrent injury to the fifth metatarsal is unrecognized varus heel deformity. Surgeons must also check for ankle instability, which may be present in this patient. A varus heel, ankle instability, and injury to the fifth metatarsal are associated with recurrent deformity.Correct Answer: A varus heel

 

1113. (1395) Q3-1766:

Which statement regarding the peroneal tendon(s) is incorrect:

 

1) The peroneus longus tendon attaches to the first metatarsal.

3) The peroneus brevis tendon has muscle attached to the tendon at a level lower than the peroneus longus tendon.

2) The peroneus brevis tendon is a plantarflexor of the ankle.

5) There are two separate retinacular sheaths for the peroneal tendons distal to the tip of the fibula.

4) The peroneus longus tendon lies anterior to the peroneus brevis tendon at the level of the distal fibula.

 

The peroneus brevis tendon plantarflexes and everts the foot and ankle. The peroneus longus tendon plantarflexes the foot, is a mild evertor of the foot, and plantarflexes the first metatarsal. The peroneus brevis tendon is prone to tears or splits at the level of the distal fibula and lies anterior to the peroneus longus tendon at this level.Correct Answer: The peroneus longus tendon lies anterior to the peroneus brevis tendon at the level of the distal fibula.

 

 

1114. (1396) Q3-1767:

A 41-year-old patient presents for treatment of a joint depression calcaneus fracture. A Sanders type IIA fracture is visible on a computerized tomography scan. After appropriate counseling, the patient elects nonoperative treatment. What is the most common complication of this injury that may subsequently occur in this patient:

 

1) Peroneal tendon dislocation

3) Calcaneofibular impingement pain

2) Achilles tendonitis

5) Tarsal tunnel syndrome

4) Subtalar arthritis

 

Subtalar arthritis occurs when a calcaneus fracture is treated nonoperatively; however, impingement of the fibula against the widened calcaneus will more frequently cause symptoms. Soft tissue problems, including tarsal tunnel syndrome, peroneal tendonitis, and sural neuritis, occur less frequently.Correct Answer: Calcaneofibular impingement pain

 

 

1115. (1397) Q3-1768:

A patient presents for treatment of a painful ankle 2 years after a hindfoot injury. He was treated nonsurgically for a calcaneus fracture that occurred when he fell. His symptoms include anterior ankle pain, weakness during pushing off, and pain along the lateral aspect of the hindfoot. On examination, he has pain to palpation at the tip of the fibula, absent inversion and eversion, 20° of plantarflexion, and no dorsiflexion. Plantarflexion strength appears adequate, and there is no compromise of the forefoot flexor function. The recommended surgical procedure is:

 

1) Anterior ankle cheilectomy and lateral calcaneus ostectomy

3) In situ subtalar arthrodesis and lateral calcaneus ostectomy

2) Anterior ankle cheilectomy and subtalar arthrodesis

5) Triple arthrodesis and Achilles tendon lengthening

4) Subtalar bone block distraction arthrodesis and lateral calcaneus ostectomy

 

This patient sustained a joint depression calcaneus fracture with a loss of the talar declination angle. He has limited dorsiflexion that is characteristic of a negative talar declination angle. This decreases the fulcrum of the Achilles tendon and weakens pushoff strength. An in situ subtalar arthrodesis may correct the subtalar joint pain but will not address the decreased height of the hindfoot and the negative talar declination angle. The negative talar declination angle can only be corrected by inserting a tricortical bone graft into the subtalar joint.Correct Answer: Subtalar bone block distraction arthrodesis and lateral calcaneus ostectomy

 

A patient presents for treatment of painful toes 1 year after open reduction and internal fixation of a calcaneus fracture. He notes difficulty with shoe wear and pain on ambulation. On examination, there are fixed claw toe deformities of the second, third, and fourth toes that are painful. The most likely cause of the toe deformities is:

 

1) Entrapment of the medial plantar nerve

3) Tethering of the flexor hallucis longus under the sustentaculum tali

2) Flexor digitorum longus stenosis associated with entrapment in the deep muscle layer of the foot

5) Unrecognized compartment syndrome of the foot

4) Unrecognized injury to the forefoot at the time of the original calcaneus fracture

 

Claw toe deformities after calcaneus fracture occur as a result of untreated compartment syndrome. Compartment syndrome occurs as a result of intrinsic muscle atrophy or fibrosis of the short flexor muscles followed by fixed toe deformity.Correct Answer: Unrecognized compartment syndrome of the foot

 

 

1117. (1399) Q3-1770:

 

 

 

Slide 1

A 56-year-old patient sustained an ankle fracture 3 years ago that was treated with closed reduction and cast immobilization. Since the injury, she has experienced pain upon ambulation and ankle stiffness. On examination, the range of motion of the ankle is 5° of dorsiflexion and 30° of plantarflexion. Crepitus with motion is not present, but the patient does experience severe pain. A radiograph is presented (Slide). The recommended procedure to alleviate the patientâs pain and improve function is:

 

1) Total ankle replacement

3) Ankle arthroscopy and joint debridement

2) Ankle arthrodesis

5) Anterior ankle cheilectomy, Achilles lengthening, and joint debridement

4) Osteotomy of the fibula

 

The arthritis in this joint is not severe, but there is joint malalignment associated with a short and externally rotated fibula. Joint malalignment is correctable with a lengthening and rotational (internal) osteotomy of the fibula with bone graft. Joint debridement, either open or arthroscopic, is not effective in the management of posttraumatic ankle arthritis. Arthrodesis and arthroplasty are not necessary at this stage.Correct Answer: Osteotomy of the fibula

 

 

 

 

 

Slide 1

A 43-year-old construction worker presents for treatment of ankle pain. The patient recounts a fall from a height that caused an ankle fracture 2 years ago. The fracture was treated with closed reduction and cast immobilization for 5 months. He experiences pain upon ambulation and is unable to work. On examination, the range of ankle motion is 5° dorsiflexion and 20° plantarflexion. There is no crepitus with motion, but severe pain is present. A radiograph is presented (Slide 1). The recommended procedure to alleviate pain and improve function is:

 

1) Total ankle replacement

3) Arthroscopy ankle and joint debridement

2) Ankle arthrodesis

5) Anterior ankle cheilectomy, Achilles lengthening, and joint debridement

4) Osteotomy of the tibia and fibula

 

The arthritis in this joint is not severe, but there is joint malalignment associated with a short and externally rotated fibula and a marked valgus tibiotalar deformity. Although arthrodesis or total ankle replacement may be considered as treatment for some patients, this patient is not a good candidate for these procedures because he does not have severe arthritis. The deformity must be corrected with an osteotomy of the tibia and fibula. Although an opening wedge osteotomy may be considered, a closing wedge procedure is easier to perform and has a higher rate of healing.Correct Answer: Osteotomy of the tibia and fibula

 

 

1119. (1401) Q3-1772:

 

 

 

Slide 1

A 29-year-old patient has had pain in her foot for 1 year. She twisted her ankle and was treated for a sprain with a brace and therapy. She has persistent pain in her foot and pain on ambulation. On examination, slight pes planus is present, pain is noted on manipulation of the foot, and there is tenderness in the midfoot and hindfoot. A radiograph is presented (Slide). The most likely cause of the pain is:

 

1) A tear of the posterior tibial tendon

3) A tear of the short plantar ligament

2) A tear of the spring ligament

5) A tear of the metatarsocuneiform ligament

4) A tear of the deltoid ligament

 

Slight abduction of the tarsometatarsal joints is noted, along with arthritis of the medial and middle columns of the midfoot. This likely resulted from a tear of the ligament between the base of the second metatarsal and the medial cuneiform (Lisfranc ligament).Correct Answer: A tear of the metatarsocuneiform ligament

 

 

 

 

 

Slide 1 Slide 2

A 53-year-old man presents with a swollen foot. He does not recall any injury to the foot, and he has minimal pain. He does not have any pertinent medical history. The clinical and radiographic appearance of the foot is presented (Slide 1 and Slide 2).

Based upon the information, the recommended treatment of this injury is:

 

1) Open reduction and internal fixation (ORIF)

3) Open reduction and primary arthrodesis

2) No weight bearing and immobilization in a removable boot

5) Debridement of the foot, deep tissue cultures, and organism-specific intravenous antibiotics

4) Hospitalization, bedrest, and intravenous antibiotics

 

Patients with neuropathy may present for the first time with a neuropathic dislocation (Charcot neuroarthropathy) even before the cause of the neuropathy is diagnosed. The recommended treatment of an acute neuropathic midfoot dislocation is open reduction and primary arthrodesis. Although ORIF without arthrodesis may be considered, recurrent deformity frequently occurs.Correct Answer: Open reduction and primary arthrodesis

 

 

1121. (1403) Q3-1774:

 

 

 

Slide 1

A 49-year-old woman has had swelling in the posterior aspect of the ankle for 5 years (Slide). The pain is focal and does not radiate. She notes that pain is worse with activity, exercise, and shoe wear. Which of the following is not an acceptable treatment for this patient:

 

1) Short leg cast immobilization

3) Debridement of the insertion of the Achilles tendon

2) High heel shoe with no heel counter

5) Achilles stretching exercises and physical therapy modalities including corticosteroid application

4) Osteotomy of the calcaneus

 

Insertional Achilles tendinopathy is aggravated by a hard heel counter on the shoe, a flat shoe, or exercise without stretching. Therapy modalities are effective for treatment of this condition. If patients do not respond to nonoperative measures, then surgery with debridement of the Achilles tendon and posterior calcaneus may be required. Osteotomy of the calcaneus (as opposed to ostectomy) is not an effective treatment.Correct Answer: Osteotomy of the calcaneus

 

 

 

 

 

Slide 1

This slide (the arrow is pointing in the direction of the pathology) illustrates which of the following conditions of the Achilles tendon:

 

1) Chronic degenerative tendinosis

3) Acute inflammatory tendinopathy

2) Acute paratendinitis

5) Chronic myxoid degeneration

4) Acute tendon rupture

 

This ultrasound is a longitudinal section of the Achilles tendon demonstrating acute rupture. Note the defect in continuity of the tendon below the skin surface. No tendon defects are noted in paratendinitis and tendinosis.Correct Answer: Acute tendon rupture

 

 

1123. (1405) Q3-1776:

Which of the statements regarding paratendinitis of the Achilles tendon is true:

 

1) Paratendinitis of the Achilles tendon is commonly associated with racket sports.

3) Paratendinitis of the Achilles tendon is effectively treated with Achilles stretching and orthoses.

2) Paratendinitis of the Achilles tendon is common in patients who have a cavus foot.

5) Paratendinitis of the Achilles tendon leads to chronic rupture of the tendon.

4) Paratendinitis of the Achilles tendon is associated with tendon degeneration.

 

Paratendinitis of the Achilles tendon is commonly associated with runners who hyperpronate. Paratendinitis of the Achilles tendon is amenable to stretching, physical therapy treatments, and an orthotic support that controls rapid pronation during the flat foot phase of gait. Although the condition can become chronic and require surgery, it does not lead to or predispose to a degenerative rupture.Correct Answer: Paratendinitis of the Achilles tendon is effectively treated with Achilles stretching and orthoses.

 

 

1124. (1406) Q3-1777:

A 65-year-old woman presents for treatment of a painful flatfoot condition. On examination, the hindfoot is in marked valgus and a rupture of the posterior tibial tendon is noted. The recommended treatment is a transfer of the flexor digitorum longus tendon and a medial translational osteotomy of the calcaneus. The rationale for the osteotomy includes all of the following except:

 

1) To increase the ground reaction forces medially

3) To improve the weight bearing tripod effect of the foot

2) To make the Achilles tendon vector lateral to the axis of the subtalar joint

5) To decrease the valgus force of the gastrocnemius on the hindfoot

4) To augment the flexor transfer medially

 

A medial translational osteotomy of the calcaneus shifts the axis of the Achilles tendon insertion medial to the axis of the subtalar joint. In doing so, the lateralizing force of the gastrocnemius on the heel is lessened and the medial tendon shift augments the strength of the flexor digitorum longus transfer and improves the mechanical efficiency of the foot by altering the ground reaction forces.Correct Answer: To make the Achilles tendon vector lateral to the axis of the subtalar joint

 

Which of the following muscles has the largest cross-sectional diameter:

 

1) Flexor hallucis longus

3) Peroneus longus

2) Flexor digitorum longus

5) Extensor digitorum longus

4) Peroneus brevis

 

Following the muscles of the gastrocnemius soleus muscle group, the flexor hallucis longus is the most powerful flexor of the ankle. The flexor hallucis longus is almost twice as strong as the flexor digitorum longus. These are important factors when planning tendon transfers in the foot and ankle.Correct Answer: Flexor hallucis longus

 

 

1126. (1408) Q3-1779:

After surgery to the hallux, a patient complains of burning and numbness along the medial aspect of the first metatarsal. The numbness extends from the medial cuneiform distally to the midportion of the first metatarsal and junction of the plantar and dorsal skin. The nerve involved with the pain is the:

 

1) Intermediate dorsal cutaneous branch superficial peroneal

3) Medial cutaneous branch superficial peroneal

2) Medial cutaneous branch deep peroneal

5) Intermediate cutaneous branch deep peroneal

4) Dorsal cutaneous branch medial plantar

 

The branches of the various sensory nerves of the foot are important to understand. The normal and aberrant topographic anatomy is important in any foot surgery, and management of posttraumatic neuritis is contingent upon an understanding of the anatomy.Correct Answer: Medial cutaneous branch superficial peroneal

 

 

1127. (1409) Q3-1780:

The most common complication after resection arthroplasty (Keller) of the base of the hallucal proximal phalanx for correction of hallux valgus is:

 

1) Recurrent hallux valgus

3) Stiffness of the hallux metatarsophalangeal joint

2) Hallux varus

5) Stress fracture of the second metatarsal

4) Cock-up deformity of the hallux

 

Resection of the base of the hallucal proximal phalanx detaches the volar plate and the medial and lateral head of the flexor brevis tendon. This leads to weakening of plantarflexion strength and dorsal contracture. The weakness may also lead to lateral overload, metatarsalgia, and stress fracture.Correct Answer: Cock-up deformity of the hallux

 

 

1128. (1410) Q3-1781:

A patient sustains a fracture of the anterior process of the calcaneus. What ligament is responsible for avulsion of this bone:

 

1) Short plantar

3) Anterior talofibular

2) Long plantar

5) Bifurcate

4) Calcaneofibular

 

The bifurcate ligament extends from the anterior process of the calcaneus to the cuboid and navicular. In certain plantarflexion and inversion injuries of the hindfoot, the ligament, which is strong, will avulse the anterior process of the calcaneus.Correct Answer: Bifurcate

 

 

 

 

 

Slide 1

The ball and socket ankle deformity shown (Slide) is associated with all of the following except:

 

1) A short femur

3) A talocalcaneal fusion

2) A short fibula

5) Missing lateral rays of the foot

4) Cavovarus

 

A ball and socket ankle deformity is caused by limited motion of the peritalar joints, particularly the subtalar and talonavicular joints, during childhood. For example, a talonavicular coalition limits inversion and eversion, and the tibiotalar joint compensates for this loss by increasing motion in the horizontal plane. As motion is increased in the horizontal plane, the medial and lateral edges of the tibiotalar articulation round off and the ball and socket joint develops.Correct Answer: Cavovarus

 

 

1130. (1412) Q3-1784:

A patient wants a below the knee amputation. As an alternative, you recommend a Syme amputation. What is the most relevant factor that would contraindicate performing a Syme amputation:

 

1) A metastatic tumor to the forefoot

3) A primary tumor in the forefoot and midfoot

2) Severe infection in the foot

5) Trauma to the hindfoot

4) Peripheral vascular disease

 

Although the Syme amputation was once popular because it allowed patients to ambulate for short distances (e.g., around their house) without using a prosthesis, surgeons now perform more below the knee amputations because of newer prosthetic designs. The Syme procedure still remains in our surgical armamentarium.

 

The only factor listed in the answer choices that may preclude amputation at this level is peripheral vascular disease. A more important factor that would contraindicate performing a Syme amputation is perfusion to the heel pad.Correct Answer: Peripheral vascular disease

 

 

1131. (1413) Q3-1786:

Which of the following statements regarding a fracture of the junction of the proximal metaphyseal and diaphyseal portion of the fifth metatarsal is false:

 

1) A fracture of the junction of the proximal metaphyseal and diaphyseal portion of the fifth metatarsal is the least likely of all fifth metatarsal fractures to heal.

3) The mechanism of injury is forced abduction.

2) Fractures treated nonoperatively heal from medial to lateral on serial radiographs.

5) Up to one-third of patients treated with casting may refracture in long-term follow-up.

4) Radiographic evidence of union lags behind clinical healing examination.

 

The fracture of the junction of the proximal metaphyseal and diaphyseal portion of the fifth metatarsal, otherwise known as the Jones fracture, causes complications with bone healing. The fracture is caused by a plantarflexion inversion twist of the foot and ankle and needs prompt treatment because nonunion rates are high with this type of fracture.Correct Answer: The mechanism of injury is forced abduction.