ORTHOPEDICS HYPERGUIDE MCQ 451-500

451. (3639) Q1-7416:

What is the most frequent intraoperative complication during the course of shoulder arthroplasty for rheumatoid arthritis?

1) Pulmonary embolism

3) Deltoid tearing

2) Cervical spine instability

5) PeriprosthetiChumeral fracture

4) Nerve injury

Poor quality bone is one of the primary challenges when performing a shoulder arthroplasty in a patient with rheumatoid arthritis. PeriprosthetiChumeral fracture is the most frequent intraoperative complication in this patient population

■Correct Answer: PeriprosthetiChumeral fracture

452. (3640) Q1-7417:

Among patients with a stiff shoulder or severe scarring, what approach can be used to minimize potential intraoperative complications:

1) Transacromial approach

3) Superior approach

2) Posterior approach

5) Anteromedial approach

4) Direct lateral approach

The anteromedial approach is a safe and effective approach when performing shoulder arthroplasty in patients with severe stiffness and poor quality tissue

■Correct Answer: Anteromedial approach

453. (3641) Q1-7418:

In addition to routine medical clearance prior to surgery, what additional test should be considered in patients with rheumatoid arthritis:

1) Hip radiographs

3) Wrist radiographs

2) Knee radiographs

5) Cervical spine: Flexion-extension views

4) Hand radiographs

A significant incidence of cervical spine disease exists among patients with rheumatoid arthritis. Surgeons should consider obtaining cervical spine flexion-extension views to evaluate for potential instability prior to the patient undergoing anesthesia

■Correct Answer: Cervical spine: Flexion-extension views

454. (3642) Q1-7419:

The most common technical cause of dislocation after primary total hip arthroplasty (THA) is:

1) Implant failure

3) Component malposition

2) Infection

5) NeurologiCdysfunction

4) Muscle weakness

Although neurologiCdysfunction, soft tissue laxity, and loosening due to implant failure or infection contribute to THA instability, component malposition is the leading cause of dislocation from surgical technique

■Correct Answer: Component malposition

455. (3643) Q1-7420:

Which of the following is not a consequence of acetabular shell malposition:

1) Fibrous ingrowth

3) Increased bearing wear

2) Increased fretting wear

5) Limited range of motion

4) Impingement

Malposition leads to limited range of motion, impingement, and increased bearing and fretting wear. Fibrous ingrowth is most commonly a consequence of inadequate fixation and excessive micromotion

■Correct Answer: Fibrous ingrowth

456. (3644) Q1-7421:

Excessive anteversion of the acetabular cup may lead to:

1) Cup medialization

3) Leg length discrepancy

2) Posterior implant impingement

5) Dislocation with excessive internal rotation

4) Premature osteolysis

Excessive anteversion leads to anterior dislocation due to posterior component impingement. This most commonly occurs through extension and external rotation of the lower extremity. Excessive anteversion has little or no direct effect on medialization of the cup, leg length disparity, or premature osteolysis

■Correct Answer: Posterior implant impingement

457. (3645) Q1-7422:

Mechanical guide inaccuracy in cup placement during total hip arthroplasty occurs due to:

1) AnatomiCsoft tissue variance

3) Poor implant fixation

2) Displaced fracture of acetabulum

5) PelviCpositional instability

4) Excessive motion between guide and implant

With adequate exposure, compensation for soft tissue variance is accomplished. Fracture is uncommon, as is gross motion between implant and bone. Provided the guide is used correctly, there is no appreciable motion between it and the implant. Changes in pelviCand patient position, however, will render the mechanical guide inaccurate

■Correct Answer: PelviCpositional instability

458. (3646) Q1-7423:

Excessive abduction of the acetabular shell may result in all of the following except:

1) Edge loading

3) Osteolysis

2) Superior instability

5) Linear polyethylene wear

4) Superior cup migration

Edge loading, superior dislocation or subluxation, linear polyethylene wear and resultant premature osteolysis may all result from an excessively abducted cup. Superior cup migration is most commonly a consequence of a cup with low abduction

■Correct Answer: Superior cup migration

459. (3647) Q1-7424:

Longevity of traditional total hip arthroplasty in young patients is limited by:

1) Implant failure

3) Fracture

2) Infection

5) Limited range of motion

4) Osteolysis and aseptiCloosening

Although implant failure, infection, and fracture occur with extended lifetime of hip implants, polyethylene wear debris and eventual aseptiCloosening are the most commonly recognized limitation in the survival of total hip arthroplasty. Limited range of motion is a less common presentation for implant failure in the hip

■Correct Answer: Osteolysis and aseptiCloosening

460. (3648) Q1-7425:

Advantages of metal-on-metal vs metal-on-polyethylene  articulation include:

1) Metal ion generation

3) Lower infection rate

2) Capacity for large head diameter

5) Lower cost

4) Increased bearing wetability

Metal ions generated, although of unknown consequence, are not considered an advantage. Metal-on-metal bearings have not been shown to demonstrate a lower infection rate or lower cost, nor do they have increased wetability (commonly associated with ceramiCbearings). The metal-on-metal implants allow larger head and cup diameter, thus providing improved range of motion with lower risk for dislocation

■Correct Answer: Capacity for large head diameter

461. (3649) Q1-7426:

Which of the following cannot be modified during hip resurfacing:

1) Cup medialization

3) Leg length

2) Femoral component angle

5) Cup angle

4) Cup size

All of the above variables can be modified during the planning and placement of hip resurfacing with the exception of leg length. Due to the anatomiCreproduction of the cup center and femoral head anatomy, modifications on leg length cannot be performed with hip resurfacing

■Correct Answer: Leg length

462. (3650) Q1-7427:

The most common failure mechanism in hip resurfacing is:

1) Acetabular component loosening

3) Recurrent dislocation

2) Infection

5) Fracture

4) Femoral component loosening

Among outcome studies, the most common failure mechanism for hip resurfacing is femoral neck fracture. Dislocation, infection, and loosening have been reported at lower rates

■Correct Answer: Fracture

463. (3651) Q1-7428:

Potential contraindication for primary hip resurfacing include all of the following except:

1) Excessive femoral cyst formation

3) Previous femoral neck fracture

2) Osteoporosis with low bone density t-score

5) Osteonecrosis with femoral head collapse

4) Severe developmental hip dysplasia

Excessive cyst formation in the femoral head, documented osteoporosis, severe developmental hip dysplasia, and advanced osteonecrosis are contraindications to hip resurfacing. Previous femoral neck fracture, however, if healed, does not provide a risk for femoral neck fracture

■Correct Answer: Previous femoral neck fracture

464. (3652) Q1-7429:

Failure of first-generation cementless femoral stems is attributed to:

1) Material composition

3) Wear particle migration

2) Malrotation

5) Fracture

4) Fatigue failure

Initial stem design of cementless stems included patch porous coating. This design feature resulted in wear particle migration distally, causing inevitable aseptiCloosening. The remaining options were not instrumental in cementless stem loosening

■Correct Answer: Wear particle migration

465. (3653) Q1-7430:

Evidence of cementless acetabular implant loosening is radiographically observed as:

1) Surrounding cystiClesions

3) Increased radiodensity

2) HeterotopiCbone formation

5) Radiolucency surrounding the shell

4) Implant spot welds

Of the choices listed, only radiolucency provides evidence of acetabular loosening. CystiClesions, known as osteolysis, may exist without the presence of loosening

■Correct Answer: Radiolucency surrounding the shell

466. (3654) Q1-7431:

Increased scintigraphiCactivity surrounding an implant may signal all of the following except:

1) Recent implantation

3) Osteolysis

2) Quiescent heterotopiCbone

5) Infection

4) Loosening

Bone scan studies are sensitive, but poorly specific. The differential includes recent implantation (up to 1 year), osteolysis, loosening, fracture, and infection. Mature heterotopiCossification is generally cold on bone scan

■Correct Answer: Quiescent heterotopiCbone

467. (3655) Q1-7432:

Imaging of pelviCbone loss around the acetabulum is best accomplished with:

1) PelviCJudet views

3) PelviCinlet view

2) Computed tomography (CT) scan

5) PelviCoutlet view

4) Cross-table lateral of affected hip

Studies have shown CT scans to be the most thorough means of assessing bone loss in the presence of osteolysis in the pelvis

■Correct Answer: Computed tomography (CT) scan

468. (3656) Q1-7433:

The ideal range of micromotion to stimulate bone ingrowth into cementless implants is:

1) Less than 20 microns

3) 200 microns to 500 microns

2) 30 microns to 150 microns

5) Greater than 900 microns

4) 600 microns to 800 microns

Ideal values of micromotion that stimulate bone ingrowth are 28 microns to 150 microns. Values greater than 150 microns are associated with fibrous ingrowth

■Correct Answer: 30 microns to 150 microns

469. (3657) Q1-7434:

Which of the following is a risk factor for the development of a postoperative periprosthetiCfracture of the humerus:

1) Diabetes

3) Age

2) Female gender

5) Polyethylene-induced osteolysis

4) Diagnosis of avascular necrosis

Osteolysis, osteopenia, and aggressive cortical reaming have been reported as potential risk factors for the development of a postoperative periprosthetiCfracture

■Correct Answer: Polyethylene-induced osteolysis

470. (3658) Q1-7435:

What nerve is most frequently injured at the time of a periprosthetiCfracture of the humerus:

1) Median nerve

3) Radial nerve

2) Ulnar nerve

5) Axillary nerve

4) Musculocutaneous nerve

The radial nerve is the most frequently injured nerve at the time of a periprosthetiCfracture. There continues to be debate as to whether the presence of a radial nerve injury constitutes a reason for revision surgery

■Correct Answer: Radial nerve

471. (3659) Q1-7436:

What is the average length of time for a periprosthetiChumeral fracture to heal with operative treatment:

1) Less than 30 days

3) Between 90 and 120 days

2) Between 30 and 90 days

5) Greater than 240 days

4) Between 120 and 240 days

In a study by Kumar and colleagues, the mean time to healing among patients who underwent surgery was 278 days (range, 135 to 558 days)

■Correct Answer: Greater than 240 days

472. (3660) Q1-7437:

According to the classification system of Wright and Cofield, what constitutes a type A periprosthetiChumeral fracture:

1) Fracture at the tip of the prosthesis, extends proximally

3) Prosthesis tip with extension distally

2) Prosthesis tip without extension

5) Distal to the tip of prosthesis

4) Fracture present with a loose prosthesis

According to the classification, a type A fracture is one at the tip of the prosthesis and extends proximally. Type B fractures occur at the prosthesis tip without extension or with a minimal amount of proximal extension and a variable amount of distal extension. Type Cfractures are distal to the tip of prosthesis

■Correct Answer: Fracture at the tip of the prosthesis, extends proximally

473. (3661) Q1-7438:

What is the preferred treatment for a type CperiprosthetiCfracture with a well-fixed humeral component:

1) Open reduction internal fixation with a plate

3) Strut allograft and cerclage wires

2) Long stem prosthesis

5) Long stem with a strut

4) Nonoperative treatment

In patients with a type CperiprosthetiCfracture (distal to the tip of the prosthesis) and a well-fixed humeral component, the injury can be treated similar to a closed humerus fracture

■Correct Answer: Nonoperative treatment

474. (3754) Q1-7535:

The approximate distance of the axillary nerve from the lateral border of the acromion is:

1) 1 cm

3) 5 cm

2) 3 cm

5) 10 cm

4) 7 cm

The axillary nerve is located approximately 5 cm from the lateral border of the acromion. Correct Answer: 5 cm

475. (3755) Q1-7536:

Which of the following nerves enters the coracobrachialis muscle distal to the tip of the coracoids:

1) Radial nerve

3) Median nerve

2) Ulnar nerve

5) Axillary nerve

4) Musculocutaneous nerve

The musculocutaneous nerve enters the coracobrachialis muscle 4 cm to 8 cm distal to the tip of the coracoid process. Correct Answer: Musculocutaneous nerve

476. (3756) Q1-7537:

Which of the following approaches is used when the deltoid is taken down off the clavicle and anterior acromion:

1) Superior approach

3) Direct approach

2) Anterosuperior approach

5) Medial approach

4) Anteromedial approach

The anteromedial approach involves taking the deltoid down off the clavicle and anterior acromion. Correct Answer: Anteromedial approach

477. (3757) Q1-7538:

The deltoid inserts on this surface of the clavicle:

1) Superior surface

3) Inferior surface

2) Anterior surface

4) All of the above

The origin of the deltoid on the clavicle is J-shaped and extends from the midline on the superior aspect of the clavicle around the front of the clavicle to the inferior portion of the anterior aspect of the clavicle. Full-thickness fascial flaps must be obtained when the deltoid is released from the clavicle.

Correct Answer: All of the above

478. (3758) Q1-7539:

Which of the following is an indication for an anteromedial approach:

1) Post-traumatiCarthritis with severe scarring

3) Revision shoulder arthroplasty

2) Rheumatoid arthritis

4) All of the above

The anteromedial approach facilitates shoulder arthroplasty in patients with severe scarring, distortion of anatomy, as well as patients with frail bone and soft tissue.

Correct Answer: All of the above

479. (4066) Q1-7540:

What are the contraindications for a corrective osteotomy for a proximal humerus malunion:

1) Glenohumeral arthritis

3) Articular incongruity

2) Massive rotator cuff tear

5) All of the above

4) Avascular necrosis

Corrective osteotomy is an option for surgeons who must treat a patient with a proximal humerus malunion. This option may best be considered in a young, active patient who has no radiographiCevidence of degenerative changes in the glenohumeral joint. In an older, less active patient who has evidence of degenerative joint disease, a shoulder arthroplasty may be a more suitable and definitive procedure.

Patients with proximal humerus malunions often present with complaints of pain as well as loss of function. Frequently, patients have impingement-type pain due to a malunion of the greater tuberosity with an associated decrease in the subacromial space. Some of the contraindications to a corrective osteotomy include a massive irreparable rotator cuff tear, significant degenerative changes of the articular surfaces, avascular necrosis, active infection, or nerve injury.

Correct Answer: All of the above

480. (3759) Q1-7541:

What is the most significant factor affecting the results of shoulder arthroplasty for a malunion:

1) Placement of a glenoid component

3) Resurfacing arthroplasty of the humerus

2) Placement of a reverse shoulder arthroplasty

5) Performing a biceps tenodesis

4) Avoidance of performing a tuberosity osteotomy

Boileau and colleagues reported that the most significant factor affecting results of shoulder arthroplasty for malunion was the need for greater tuberosity osteotomy.

Correct Answer: Avoidance of performing a tuberosity osteotomy

481. (3760) Q1-7542:

When considering arthroscopiCtreatment of a malunion, what is the procedure most frequently performed:

1) Biceps tenodesis

3) ArthroscopiCcapsular release

2) Superior labral anterior posterior (SLAP) repair

5) Tuberoplasty

4) Acromioplasty

ArthroscopiCacromioplasty has been reported by Beredjiklian and colleagues. The procedure essentially increases the available subacromial space to improve impingement of the greater tuberosity against the acromion.

Correct Answer: Acromioplasty

482. (3761) Q1-7543:

What are the complications commonly associated with tuberosity osteotomy at the time of shoulder arthroplasty for malunion:

1) Nonunion of the tuberosity

3) Malunion of the tuberosity

2) Tuberosity resorption

4) All of the above

Antuna and colleagues reported that 10 of 24 shoulders that had a greater tuberosity osteotomy had a complication related to tuberosity nonunion, malunion, or resorption.

Correct Answer: All of the above

483. (3762) Q1-7544:

Which of the following intraoperative techniques can be used to avoid tuberosity osteotomy:

1) Placement of the stem in slight varus

3) Placement of the stem in slight valgus

2) Bending the stem to accommodate the deformity

4) All of the above

Implantation of the humeral component in slight varus or valgus to accommodate the tuberosity malunion was not associated with an increased incidence of humeral component loosening. In addition, humeral components with a modified curvature in the stem have been used with success.

Correct Answer: All of the above

484. (3763) Q1-7545:

What are the potential benefits of performing a lesser tuberosity osteotomy:

1) Bone-to-bone healing

3) Ability to detect on radiographs disruption of the anterior repair

2) Improved glenoid exposure

4) All of the above

A lesser tuberosity osteotomy allows bone-to-bone healing as well as facilitates glenoid exposure. Moreover, disruption of the anterior repair is immediately evident on postoperative radiographs with the appearance of a displaced lesser tuberosity.

Correct Answer: All of the above

485. (3764) Q1-7546:

What are the potential benefits of performing magnetiCresonance imaging (MRI) of a shoulder arthroplasty with a suspected rotator cuff tear:

1) Assess degree of fatty atrophy

3) Evaluate the size of the tear

2) Define the location of the tear

4) All of the above

An MRI allows a surgeon to gain a greater understanding of the size of the rotator cuff tear, the specifiClocation of the tear, and the degree of fat infiltration within the tendon.

Correct Answer: All of the above

486. (3765) Q1-7547:

In an elderly patient with a postoperative rotator cuff tear and escape, which of the following options is most effective to create a stable shoulder arthroplasty:

1) Coracohumeral reconstruction with an Achilles tendon graft

3) Hemiarthroplasty

2) Bipolar arthroplasty

4) Reverse shoulder arthroplasty

Many patients with a rotator cuff tear following shoulder arthroplasty may develop anterior-superior escape. Once this pattern develops, it may be difficult to restore stability with attempted rotator cuff repair alone. In this setting, one may consider the use of a reverse arthroplasty, particularly if the patient is older than 70 years of age.

Correct Answer: Reverse shoulder arthroplasty

487. (3766) Q1-7548:

What is the reported frequency of rotator cuff tear following shoulder arthroplasty:

1) Less than 1%

3) 3% to 4%

2) 1% to 2%

4) Greater than 5%

The reported frequency of postoperative rotator cuff tears following shoulder arthroplasty is 3% to 4%. Correct Answer: 3% to 4%

488. (3767) Q1-7549:

What are some potential benefits of performing arthroscopiCcompared to open acromioplasty in a patient who develops impingement syndrome following hemiarthroplasty:

1) Ability to evaluate the status of the glenoid

3) More rapid postoperative recovery

2) Capacity to address intra-articular pathology

5) All of the above

4) Less violation of the deltoid

ArthroscopiCacromioplasty has been used for the treatment of impingement following shoulder arthroplasty. It has the potential benefits of less tissue disruption, more rapid recovery, as well as increased ability to address intra-articular pathology compared to an open procedure.

Correct Answer: All of the above

489. (3867) Q1-7650:

Which medication has been identified as a risk factor for a nerve injury after shoulder arthroplasty:

1) Prednisone

3) Clopidogrel bisulfate

2) Warfarin

5) Methotrexate

4) Aspirin

Methotrexate has been identified as a risk for development of a nerve injury after shoulder arthroplasty. Correct Answer: Methotrexate

490. (3868) Q1-7651:

Which is the most common mechanism for nerve injury after shoulder arthroplasty:

1) Laceration

3) Contusion

2) Expanding hematoma

5) Temporary neuropraxia due to stretch

4) Tearing

The most common reason for a nerve deficit following shoulder arthroplasty is a temporary neuropraxia due to stretch. Correct Answer: Temporary neuropraxia due to stretch

491. (3869) Q1-7652:

Which approach has been identified as a risk factor for the development of a nerve injury with shoulder arthroplasty:

1) Transacromial

3) Superior

2) Anteromedial

5) Deltopectoral

4) Posterior

The deltopectoral approach has been identified as a risk for development of a nerve injury after shoulder arthroplasty. Correct Answer: Deltopectoral

492. (3870) Q1-7653:

Which nerve is most likely to have evidence of a deficit after shoulder arthroplasty:

1) Radial nerve

3) Musculocutaneous nerve

2) Ulnar nerve

5) Axillary nerve

4) Median nerve

The most common nerve that has been found to have a deficit after shoulder arthroplasty is the axillary nerve. Correct Answer: Axillary nerve

493. (3871) Q1-7654:

Which of the following is the reported incidence of nerve injuries following total shoulder arthroplasty:

1) Less than 1%

3) Between 2% and 4%

2) Between 1% and 2%

5) Greater than 10%

4) Between 4% and 5%

The reported incidence of nerve injuries following shoulder arthroplasty is 4.3%. Correct Answer: Between 4% and 5%

494. (3877) Q1-7660:

Which is the most common reason for revision surgery among patients who undergo hemiarthroplasty:

1) Humeral component loosening

3) Infection

2) PeriprosthetiCfracture

5) Glenoid arthritis

4) Instability

Painful glenoid arthritis represents the most common reason for revision surgery for hemiarthroplasties. Correct Answer: Glenoid arthritis

495. (3878) Q1-7661:

Which of the following are nonanatomiCinstability procedures:

1) Bristow

3) Magnuson-Stack

2) Putti-Platt

5) All of the above

4) Latarjet

Among patients who have undergone prior instability surgery, it is important to review prior operative reports to determine the specifiCinstability procedure performed. This will facilitate safe and effective soft tissue releases and balancing at the time of shoulder arthroplasty.

Correct Answer: All of the above

496. (3879) Q1-7662:

Which is the mean 10-year survival for shoulder arthroplasty after prior instability surgery:

1) Greater than 95%

3) Between 75% and 85%

2) Between 85% and 95%

5) Less than 65%

4) Between 65% and 75%

Overall, the survival rate for shoulder arthroplasty after prior instability surgery was only 61% at 10 years. Correct Answer: Less than 65%

497. (3880) Q1-7663:

Compared to shoulder arthroplasty for primary osteoarthritis, shoulder arthroplasty after prior instability surgery is associated with which of the following:

1) Lower revision rate

3) Higher revision rate

2) Similar revision rate

Research has shown that shoulder arthroplasty for postcapsulorraphy arthritis has inferior results and a higher revision rate compared to shoulder arthroplasty for osteoarthritis.

Correct Answer: Higher revision rate

498. (3881) Q1-7664:

Which are the most common complications after shoulder arthroplasty for instability associated arthritis:

1) Instability

3) Glenoid arthritis

2) Component failure

4) All of the above

Shoulder arthroplasty for postcapsulorraphy arthritis provides pain relief and improved motion. However, shoulder arthroplasty in these young patients is associated with a high rate of unsatisfactory results and revision surgery due to glenoid arthritis, component failure, or instability.

Correct Answer: All of the above

499. (3901) Q1-7781:

What anatomiCfactor has been identified as placing a patient at an increased risk for re-tearing a rotator cuff after repair:

1) Greater tuberosity foot print less than 2 cm in width

3) Increased humeral retroversion

2) Wide lateral extension of the acromion

5) Narrow bicipital groove

4) Increased inclination of the humeral neck

Zumstein and colleagues identified a wide lateral extension of the acromion as a risk factor for developing a recurrent rotator cuff tear.

Correct Answer: Wide lateral extension of the acromion

500. (3902) Q1-7782:

What are some of the potential benefits of using ultrasound to evaluate the integrity of the rotator cuff:

1) Portable device

3) DynamiCevaluation

2) Low cost compared to magnetiCresonance imaging (MRI)

5) All of the above

4) Noninvasive procedure

Ultrasound has become increasingly popular as a tool to evaluate rotator cuff tears. Some of the advantages of ultrasound include the fact that it is easily portable and less expensive than MRI. Additionally, unlike a computed tomography arthrogram, no injection is required. Another interesting aspect of ultrasound is that it allows dynamiCevaluation of the rotator cuff. Several research studies have shown the promise of using ultrasound to follow the status of rotator cuff after repair.

Correct Answer: All of the above