Hand and wrist: Answers

MCQs

1. d.      Central slip rupture.

Swan neck deformity is secondary to an imbalance between flexors and extensors with a variable contribution from the intrinsic muscles. Central slip rupture is the cause of a Boutonnière deformity.

2. d.      Bone, Extensor, Flexor, Artery, Nerve, Vein.

This is a well-known order. A useful way of remembering it is BE a FAN of V. A stable platform is needed for reconstruction. Then the deep structures must be repaired before the delicate arterial and nerve repairs.

3. a.      A2 and A4.

Any exposure of the flexor tendons in their sheath and pulley system runs the risk of disrupting a magnificent engineering wonder. The pulleys serve a very important function in creating strong lever arms for the tendons. The most important of these are the A2 and A4 pulleys. Transection results in ‘bow-stringing’ with subsequent weakness of flexion.

4. b.      Adductor aponeurosis interposition between the distally based avulsed ligament impairs ligament healing.

In 1962 Stener described the lesion. It only occurs in complete rupture and it is thus important to clinically differentiate complete and incomplete ruptures. If the aponeurosis is interposed then complete healing of the distal fragment will not take place and despite the period of immobilization there will be excess ulnar laxity.

5. e.      Up to 15º of angulation of the index and middle finger can be accepted.

Most hand surgeons would agree that there is between 15 and 30 of mobility at the carpometacarpal (CMC) joint of the ring and little fingers. This allows the surgeon to accept large amounts of deformity at the distal metacarpal neck fracture. There is still poor consensus on how much deformity to accept but 70 is still reasonable. There is consensus on the index and to a lesser degree middle finger. They do not have much compensation so 10–15 is the maximum, allowed deformity. The Jahss manoeuvre must not be confused with the Jahss position (metacarpophalangeal (MCP) and proximal interphalangeal ( PIP ) flexion to 90). The manoeuvre is good, the position is no longer acceptable.

 

Postgraduate Orthopaedics, ed. Kesavan Sri-Ram. Published by Cambridge University Press.

# Cambridge University Press 2012.

6. c.      Extension and supination.

This question tests the understanding of the deforming forces of a fracture. Extension and supination are necessary to overcome the pronation rotatory deformity that the volar displaced fragment undergoes.

7. c.      Triangular fibrocartilage complex (TFCC) tear.

Once again mechanism of injury and mechanics are key to understanding the injury. Wrist pain must always be divided into radial, dorsal and ulna. Then according to the anatomy of the region, specific signs and limited special investigations a diagnosis can be made. TFCC tears are either acute or chronic and have been classified by Palmer:

Class 1 – Traumatic

1. 1. – central perforation or tear
   2. – ulnar avulsion with or without ulnar styloid fracture
   3. – distal avulsion
   4. – radial avulsion with or without sigmoid notch fracture Class 2 – Degenerative stage

7. 1. – TFCC wear
   2. – TFCC wear with lunate and/or ulnar chondromalacia
   3. – TFCC perforation with lunate and/or ulnar chondromalacia
   4. – TFCC perforation with lunate and/or ulnar chondromalacia and lunotriquetral (LT) ligament perforation
   5. – TFCC perforation with lunate and/or ulnar chondromalacia, LT ligament perforation, and ulnocarpal arthritis
8. c.      Perform a Henry’s approach and a separate carpal tunnel incision.

In severe wrist trauma the median nerve may be under a lot of pressure. It is not acceptable to watch and wait as there will only be more swelling post-operatively. The wrist crease must always be crossed with an S shape but in this case two separate incisions are key to prevent injury to the palmar cutaneous branch of the median nerve which lies between the flexor carpi radialis and palmaris longus. Safe surgery on the median nerve should not be contemplated from either a very radial or very ulnar approach.

9. e.      Scapholunate angle <60º.

This question is a test of the indications for fixation of a scaphoid fracture. The unstable fracture generally needs fixation. Other signs of instability include radiolunate angle >15, scapholunate angle >60, intrascaphoid angles >35 and a proximal pole fracture.

10. a.      Brachioradialis and extensor carpi radialis longus (ECRL) in pronation.

The superficial branch of the radial nerve is compressed as it is squeezed between the brachioradialis and ECRL in pronation. This must not be confused with intersection syndrome, pain associated with the crossing of the first and second dorsal extensor compartments associated with repetitive movements of the wrist (e.g. in rowers).

11. b.      Glomus tumour.

The give away is the bluish colour under the nail. This is typical for the glomus tumour; this is a rare benign neoplasm arsing from the glomus body (a neuromyoarterial apparatus). It can be excised by lifting the nail up (if under the nail plate) with repair of the nail bed afterwards.

12. d.      Proximal injury.

A more distal low velocity injury with a sharp object will have a better potential for healing.

The long distance to the motor endplate from a proximal injury may preclude recovery.

Younger patients have far higher potential for full recovery than adults.

13. d.      Natatory ligament.

This key question is a test of anatomy. Before considering surgery a thorough knowledge of local structures is important. The distortion of the normal anatomy results in displacement of the neurovascular structures, and explains the significant risk in Dupuytren’s disease surgery.

14. e.      No sensation from tip of acromion to tip of fingers.

The prognosis for avulsion of the roots is far worse than just rupture or traction. All of these markers suggest severe trauma and may point to root avulsion. Numbness on its own is not as worrying as the other signs.

15. c.      Tendon pull must be synergistic.

These rules must be appreciated and short cuts will only lead to disaster. Donor muscles must be expendable and have adequate power, ideally MRC grade 5. Joints must be mobile with no contracture.

16. e.      Diabetic cheirarthropathy.

This is a poorly understood condition. It is thought to be as a result of a muscular or tendon imbalance with soft tissue disruption. There is a microangiopathy of the dermal and subcutaneous blood vessels. It is more common in Type 1 diabetics and can affect 8–50% of the population. Loss of function is painless, and progresses from distal to proximal. The prayer sign is an inability to oppose palmar surfaces.

17. e.      Wrist arthrodesis.

The Lichtman classification system essentially divides Kienbock’s disease into types that can be treated with therapeutic operations such as radial shortening or grafting versus those that need salvage operations such as partial or complete wrist arthrodesis. One of the deciding factors in the type of fusion is the degree of fixed deformity. In the presence of fixed deformity radial shortening is not an option. It is also not an option in the more uncommon scenario of the ulnar positive wrist. The Lichtman classification, based on radiographs, is as follows:

Stage 1 – normal (may have a linear or a compression fracture)

Stage 2 – sclerosis but no collapse

Stage 3A – collapse of entire lunate without fixed scaphoid rotation

Stage 3B – collapse of entire lunate with fixed scaphoid rotation

Stage 4 – stage III with generalized degenerative changes in the carpus

18. a.      Ulnar shortening osteotomy.

It is uncommon for younger people to present with significant radial shortening as their fractures are usually well managed. In this case there is ulna impaction syndrome. The aim is to reduce this impaction. There is no need to address the DRUJ or replace the distal ulna. The Darrach procedure should be reserved for older patients with rheumatoid disease. It is associated with ongoing discomfort in the proximal stump and certainly not the first choice in this scenario.

19. b.      Painful nodules are an indication for surgery.

The disease is usually in its early phases. The stages, according to Luck’s classification, are proliferative, involutional and finally residual. Early surgery will certainly lead to recurrence and can stimulate the disease process. Carpal tunnel surgery must be performed at a separate occasion for a similar reason. Unfortunately in the long term recurrence rates are high (50%).

20. d.      Class 1B lesion.

TFCC tears are divided into acute (1) and chronic (2) by the Palmer classification. The majority of isolated TFCC injuries do not require early surgical management. The need for treatment is increased when the lesion is associated with fractures, instability and DRUJ injuries.

21. b.      She has a claw hand.

She has tight intrinsic muscles and her Bunnell test is positive as the intrinsic muscles are more powerful than her extrinsic extensors and flexors. The tight intrinsic muscles are treated with distal releases when fibrotic and a proximal slide when spastic. An intrinsic minus hand is one where there is a loss of function in the ulna and sometimes the median nerve (claw). The patient presents with a monkey grip.

22. c.      Quadrigia effect.

Though this was a bony avulsion it must be thought of like any other FDP tendon injury. In this case because of the proximal migration of the tendon it was probably repaired tightly with an adhesed improperly tensioned FDP. Because the adjacent remaining fingers share a common muscle belly, they cannot flex entirely (quadrigia effect).

23. a.      There is not always a scaphoid fracture.

To understand carpal instability it is essential to appreciate the ligamentous attachments both between the individual carpal bones as well as the extrinsic ligaments that support the wrist. The Mayfield staging is thus summarized:

Stage I – scapholunate dissociation/scaphoid fracture

Stage II – lunocapitate dislocation

Stage III – lunotriquetral disruption/triquetrum fracture Stage IV – lunate dislocation

24. d.      Superficial palmar arch.

The superficial palmar arch is a continuation of the ulna artery. In the majority of patients (78%) this arch is completed by branches from the deep palmar, radial or median arteries. This explains why even with significant lacerations to the ulna artery a hand can be well perfused.

25. c.      Mucoid cyst.

This is a common lesion that arises from the osteoarthritic DIP joint. There is usually a disruption of the joint and a cyst develops. They cause deformity of the nail because of pressure on the germinal matrix. If they are large it may be necessary to perform a local flap at excision ( transposition ).

26. a.      Nerve stimulation therapy.

If symptoms are not severe and there is not significant and progressive neuropathy then non-operative management must be considered. This includes splintage, hand therapy, steroid injection and even yoga has been proven to be beneficial. Alternatively a patient could be referred for either open or endoscopic release.

27. c.      Scaphoid extension.

In rheumatoid arthritis the inflammation of the synovium sets off a sequence of events that start with correctable deformity and eventually lead to fixed deformity and destruction of the joints. The synovitis at the DRUJ leads to capsular stretching with ECU subluxation and stretching of the dorsal structures. There is erosion of the radio-scapho-capitate ligament with flexion of the scaphoid. The carpus supinates as it moves in an ulna direction. Rather than the ulna becoming prominent it is the carpus that slips away from it.

28. e.      Nail patella syndrome.

This syndrome is a result of an abnormality on chromosome 9. Patients may have subluxed or dislocated radial heads and never realize they have a problem until they have an X-ray. The syndrome can include abnormalities of the patella and nail growth, generalized ligamentous laxity and bony exostoses.

29. d.      50%.

Because of the morbidity and prolonged rehabilitation associated with tendon repair it is advisable to repair lacerations over 50% of the tendon width. The exception to this rule is if there is visible triggering under a local anaesthetic block it may be necessary to address this.

30. b.      Sonic hedgehog protein.

Eight weeks after fertilization, all limb structures are present. It is between 4 and 8 weeks where the majority of congenital disorders in the hand occur. There are many factors involved in limb development; however, there are three key zones responsible for proximodistal, anteroposterior and dorsoventral development. These are the apical ectodermal ridge, zone of polarizing activity and Wnt pathway respectively. These in turn produce fibroblast growth factors, sonic hedgehog protein and LMX1, which all work in a coordinated manner to ensure the normal development of the limb.

EMQs

1. 1. c. Extensor carpi ulnaris (ECU) subluxation and tenosynovitis.
2. f. Vaughn–Jackson syndrome. 3. a. De Quervain’s disease.

This question is really a test of the seven extensor compartments. Each compartment has its own unique anatomy and pathology in turn. Rowers and drummers have ECU subluxation and tenosynovitis. It is common for young mothers to develop tenosynovitis of the first extensor compartment but the condition is not exclusive to them. Vaughn-Jackson syndrome is the attritional rupture of the extensor digiti minimi (EDM) in rheumatoid arthritis. The compartments are as follows:

First – abductor pollicis longus and extensor pollicis brevis tendons

Second – extensor carpi radialis longus and extensor carpi radialis brevis tendons

Third – extensor pollicis longus tendon

Fourth – three tendons of extensor digitorum muscle and the extensor indicis tendon

Fifth – extensor digiti minimi tendon Sixth – extensor carpi ulnaris

2. 1. g. Eikenella corrodens. 2. d. Herpes simplex virus type 1. 3. h. Pasteurella multocida.

The most common cause of hand infections is probably still Staphylococcus aureus. However, because the hands come into contact with specific things it is important to recognize a few important infections. A ‘fight bite’ often presents with a small wound and a history of punching. Eikenella corrodens comes from the human mouth. Dentists and healthcare workers are exposed to the herpes virus. The typical organism in cat bites is Pasteurella. The organisms in necrotizing fasciitis are multiple and usually include clostridia and Group A b- streptococci.

3. 1. f. V-Y plasty (advancement). 2. a. Cross finger flap. 3. c. Terminalization.

Knowing the plastic surgery reconstructive ladder is essential for the management of fingertip injuries. The principle is that if the wound is <1 cm and if there is no bone exposed it can probably heal on its own or be covered with skin only. If there is a bigger lesion with exposed bone then the type of lesion and location must be carefully assessed.

4. 1. c. Epithelioid. 2. g. Enchondroma. 3. e. Schwannoma.

Sarcoma and other malignancies in the hands are rare. Benign tumours and skin cancers are not. Prior to and after the excision of any lesion from the hand the surgeon must have a wide differential diagnosis at hand.

5. 1. f. Psoriasis. 2. b. Scleroderma. 3. e. Amyloidosis.

Many systemic conditions manifest in a pathognomonic manner in the hands. Certain key facts have been provided about each of the conditions. The reader is reminded that other arthritides must be considered in hand pathology.

6. 1. a. Parsonage–Turner syndrome. 2. e. Anterior interosseous nerve palsy.
   3. h. Mannerfelt–Norman syndrome.

The various compression neuropathies can be a bit tricky. The key to the anterior interosseous nerve is that it is a pure motor palsy. Pronator syndrome is a sensory deficit. Mannerfelt–Norman syndrome refers to an attrition rupture of the flexor pollicis longus due to scaphotrapezial synovitis. This question could also be asked in terms of special investigations and special tests in clinical examination.

7. 1. d. Radial shortening. 2. e. Proximal row carpectomy. 3. a. Wrist fusion.

The clues of dorsal wrist pain and Lichtman classification lead the reader to Kienbock’s disease. The question is a discriminator between treatment and salvage of the disease as well as differentiating fixed and mobile deformity (3A vs. 3 B ).

8. 1. a. Intrinsic plus hand. 2. f. Quadrigia effect. 3. b. Boutonnière deformity.

This questions tests knowledge of special signs. Intrinsic tightness as shown by the Bunell test must be differentiated from the intrinsic minus hand, e.g. loss of ulnar nerve function. A Boutonnière deformity is usually due to central slip rupture while a swan neck deformity can have many causes.

9. 1. b. Hamate hook fracture. 2. g. Ulnocarpal abutment. 3. k. Scaphoid lunate advanced collapse.

When evaluating wrist pain it is worth dividing it into dorsal, radial and ulnar-sided wrist pain. Once age and location has been taken into account the diagnosis will be narrowed down. At this stage radiographs and diagnostic injections will probably provide a definite answer. The ring sign is one of many signs that reveal widening of the scapholunate ligament and flexion of the scaphoid.

10. 1. b. Radio-scapholunate fusion. 2. c. Scaphoidectomy and four-corner fusion.
    3. a. Wrist fusion with AO fusion plate.

The aim of this question is to differentiate localized arthritis of the wrist (requiring limited arthrodesis) from pan-arthritis (requiring full fusion). Because of the capitate erosion a proximal row carpectomy is not an option and the four-corner fusion is the correct choice. In a stage IV wrist, full wrist arthrodesis is the only option.

11. 1. d. Ulnar hammer syndrome. 2. g. Raynaud’s disease. 3. c. Raynaud’s phenomenon.

The key to this question is the ability to differentiate Raynaud’s phenomenon from disease. Disease mainly affects females over a chronic period with normal lab tests. The phenomenon is a consequence of either vaso-spastic or vaso-occlusive disease. The ulnar hammer syndrome with thrombosis of the ulnar artery occurs more commonly in males around the age of 55 who smoke, and who use their hand as a hammer. The carpenter fact and the cold sensitivity are the clues.

12. 1. f. Arterial thoracic outlet syndrome. 2. d. Venous thoracic outlet syndrome.
    3. c. Disputed thoracic outlet syndrome.

Thoracic outlet syndrome is a rare condition with 95% being the disputed type with normal special tests. Cervical ribs and true arterial occlusion (i.e. secondary Raynaud’s phenomenon) is a rare cause. Muscular men tend to get venous occlusion. True neurogenic thoracic outlet syndrome is very rare secondary to nerve compression at C8/T1.

13. 1. d. Posterior interosseous nerve palsy. 2. a. Metacarpophalangeal joint ( MCPJ ) subluxation. 3. f. Tendon subluxation.

There are four reasons for a loss of finger extension in rheumatoid arthritis. In simple tendon rupture (Vaughn-Jackson syndrome vs. Jackson Pollock, who is an abstract artist) the tenodesis test will be negative. In subluxation, tenodesis test is positive. If there is a lot of inflammation at the elbow then the posterior interosseous nerve will be compromised, hence the widespread weakness involving the thumb. Lastly, MCPJ misalignment will create a problem with the pull of the tendon and hence a loss of extension. Intrinsic musculature is usually tight, not deficient.

14. 1. c. Pronator teres to extensor carpi radialis longus. 2. h. Extensor indicis to extensor pollicis longus. 3. a. Zancolli’s lasso procedure.

There are many classic and other more creative tendon transfers. It is important to know at least two transfers for each of the major upper limb nerves and understand the principles of tendon transfer. It is the rare attritional rupture of the extensor pollicis longus tendon on Lister’s tubercle that occurs in non-operatively treated fractures. The split flexor pollicis longus to extensor pollicis longus transfer-tenodesis is reserved for more complex reconstruction of pinch, in intrinsic deficiency.

15. 1. b. Hueston’s tabletop test. 2. c. Watson’s shift test. 3. f. Bunnell test.

Special tests must not only be applied to each lesion but the reader must have an understanding of the mechanism for each test. These are but a few of the more common ones and it is recommended that they are all performed even on the normal hand to get into the habit of performing these sometimes difficult tests.

Hand and wrist: Answers

MCQs

1. d.      Central slip rupture.

Swan neck deformity is secondary to an imbalance between flexors and extensors with a variable contribution from the intrinsic muscles. Central slip rupture is the cause of a Boutonnière deformity.

2. d.      Bone, Extensor, Flexor, Artery, Nerve, Vein.

This is a well-known order. A useful way of remembering it is BE a FAN of V. A stable platform is needed for reconstruction. Then the deep structures must be repaired before the delicate arterial and nerve repairs.

3. a.      A2 and A4.

Any exposure of the flexor tendons in their sheath and pulley system runs the risk of disrupting a magnificent engineering wonder. The pulleys serve a very important function in creating strong lever arms for the tendons. The most important of these are the A2 and A4 pulleys. Transection results in ‘bow-stringing’ with subsequent weakness of flexion.

4. b.      Adductor aponeurosis interposition between the distally based avulsed ligament impairs ligament healing.

In 1962 Stener described the lesion. It only occurs in complete rupture and it is thus important to clinically differentiate complete and incomplete ruptures. If the aponeurosis is interposed then complete healing of the distal fragment will not take place and despite the period of immobilization there will be excess ulnar laxity.

5. e.      Up to 15º of angulation of the index and middle finger can be accepted.

Most hand surgeons would agree that there is between 15 and 30 of mobility at the carpometacarpal (CMC) joint of the ring and little fingers. This allows the surgeon to accept large amounts of deformity at the distal metacarpal neck fracture. There is still poor consensus on how much deformity to accept but 70 is still reasonable. There is consensus on the index and to a lesser degree middle finger. They do not have much compensation so 10–15 is the maximum, allowed deformity. The Jahss manoeuvre must not be confused with the Jahss position (metacarpophalangeal (MCP) and proximal interphalangeal ( PIP ) flexion to 90). The manoeuvre is good, the position is no longer acceptable.

 

Postgraduate Orthopaedics, ed. Kesavan Sri-Ram. Published by Cambridge University Press.

# Cambridge University Press 2012.

6. c.      Extension and supination.

This question tests the understanding of the deforming forces of a fracture. Extension and supination are necessary to overcome the pronation rotatory deformity that the volar displaced fragment undergoes.

7. c.      Triangular fibrocartilage complex (TFCC) tear.

Once again mechanism of injury and mechanics are key to understanding the injury. Wrist pain must always be divided into radial, dorsal and ulna. Then according to the anatomy of the region, specific signs and limited special investigations a diagnosis can be made. TFCC tears are either acute or chronic and have been classified by Palmer:

Class 1 – Traumatic

1. 1. – central perforation or tear
   2. – ulnar avulsion with or without ulnar styloid fracture
   3. – distal avulsion
   4. – radial avulsion with or without sigmoid notch fracture Class 2 – Degenerative stage

7. 1. – TFCC wear
   2. – TFCC wear with lunate and/or ulnar chondromalacia
   3. – TFCC perforation with lunate and/or ulnar chondromalacia
   4. – TFCC perforation with lunate and/or ulnar chondromalacia and lunotriquetral (LT) ligament perforation
   5. – TFCC perforation with lunate and/or ulnar chondromalacia, LT ligament perforation, and ulnocarpal arthritis
8. c.      Perform a Henry’s approach and a separate carpal tunnel incision.

In severe wrist trauma the median nerve may be under a lot of pressure. It is not acceptable to watch and wait as there will only be more swelling post-operatively. The wrist crease must always be crossed with an S shape but in this case two separate incisions are key to prevent injury to the palmar cutaneous branch of the median nerve which lies between the flexor carpi radialis and palmaris longus. Safe surgery on the median nerve should not be contemplated from either a very radial or very ulnar approach.

9. e.      Scapholunate angle <60º.

This question is a test of the indications for fixation of a scaphoid fracture. The unstable fracture generally needs fixation. Other signs of instability include radiolunate angle >15, scapholunate angle >60, intrascaphoid angles >35 and a proximal pole fracture.

10. a.      Brachioradialis and extensor carpi radialis longus (ECRL) in pronation.

The superficial branch of the radial nerve is compressed as it is squeezed between the brachioradialis and ECRL in pronation. This must not be confused with intersection syndrome, pain associated with the crossing of the first and second dorsal extensor compartments associated with repetitive movements of the wrist (e.g. in rowers).

11. b.      Glomus tumour.

The give away is the bluish colour under the nail. This is typical for the glomus tumour; this is a rare benign neoplasm arsing from the glomus body (a neuromyoarterial apparatus). It can be excised by lifting the nail up (if under the nail plate) with repair of the nail bed afterwards.

12. d.      Proximal injury.

A more distal low velocity injury with a sharp object will have a better potential for healing.

The long distance to the motor endplate from a proximal injury may preclude recovery.

Younger patients have far higher potential for full recovery than adults.

13. d.      Natatory ligament.

This key question is a test of anatomy. Before considering surgery a thorough knowledge of local structures is important. The distortion of the normal anatomy results in displacement of the neurovascular structures, and explains the significant risk in Dupuytren’s disease surgery.

14. e.      No sensation from tip of acromion to tip of fingers.

The prognosis for avulsion of the roots is far worse than just rupture or traction. All of these markers suggest severe trauma and may point to root avulsion. Numbness on its own is not as worrying as the other signs.

15. c.      Tendon pull must be synergistic.

These rules must be appreciated and short cuts will only lead to disaster. Donor muscles must be expendable and have adequate power, ideally MRC grade 5. Joints must be mobile with no contracture.

16. e.      Diabetic cheirarthropathy.

This is a poorly understood condition. It is thought to be as a result of a muscular or tendon imbalance with soft tissue disruption. There is a microangiopathy of the dermal and subcutaneous blood vessels. It is more common in Type 1 diabetics and can affect 8–50% of the population. Loss of function is painless, and progresses from distal to proximal. The prayer sign is an inability to oppose palmar surfaces.

17. e.      Wrist arthrodesis.

The Lichtman classification system essentially divides Kienbock’s disease into types that can be treated with therapeutic operations such as radial shortening or grafting versus those that need salvage operations such as partial or complete wrist arthrodesis. One of the deciding factors in the type of fusion is the degree of fixed deformity. In the presence of fixed deformity radial shortening is not an option. It is also not an option in the more uncommon scenario of the ulnar positive wrist. The Lichtman classification, based on radiographs, is as follows:

Stage 1 – normal (may have a linear or a compression fracture)

Stage 2 – sclerosis but no collapse

Stage 3A – collapse of entire lunate without fixed scaphoid rotation

Stage 3B – collapse of entire lunate with fixed scaphoid rotation

Stage 4 – stage III with generalized degenerative changes in the carpus

18. a.      Ulnar shortening osteotomy.

It is uncommon for younger people to present with significant radial shortening as their fractures are usually well managed. In this case there is ulna impaction syndrome. The aim is to reduce this impaction. There is no need to address the DRUJ or replace the distal ulna. The Darrach procedure should be reserved for older patients with rheumatoid disease. It is associated with ongoing discomfort in the proximal stump and certainly not the first choice in this scenario.

19. b.      Painful nodules are an indication for surgery.

The disease is usually in its early phases. The stages, according to Luck’s classification, are proliferative, involutional and finally residual. Early surgery will certainly lead to recurrence and can stimulate the disease process. Carpal tunnel surgery must be performed at a separate occasion for a similar reason. Unfortunately in the long term recurrence rates are high (50%).

20. d.      Class 1B lesion.

TFCC tears are divided into acute (1) and chronic (2) by the Palmer classification. The majority of isolated TFCC injuries do not require early surgical management. The need for treatment is increased when the lesion is associated with fractures, instability and DRUJ injuries.

21. b.      She has a claw hand.

She has tight intrinsic muscles and her Bunnell test is positive as the intrinsic muscles are more powerful than her extrinsic extensors and flexors. The tight intrinsic muscles are treated with distal releases when fibrotic and a proximal slide when spastic. An intrinsic minus hand is one where there is a loss of function in the ulna and sometimes the median nerve (claw). The patient presents with a monkey grip.

22. c.      Quadrigia effect.

Though this was a bony avulsion it must be thought of like any other FDP tendon injury. In this case because of the proximal migration of the tendon it was probably repaired tightly with an adhesed improperly tensioned FDP. Because the adjacent remaining fingers share a common muscle belly, they cannot flex entirely (quadrigia effect).

23. a.      There is not always a scaphoid fracture.

To understand carpal instability it is essential to appreciate the ligamentous attachments both between the individual carpal bones as well as the extrinsic ligaments that support the wrist. The Mayfield staging is thus summarized:

Stage I – scapholunate dissociation/scaphoid fracture

Stage II – lunocapitate dislocation

Stage III – lunotriquetral disruption/triquetrum fracture Stage IV – lunate dislocation

24. d.      Superficial palmar arch.

The superficial palmar arch is a continuation of the ulna artery. In the majority of patients (78%) this arch is completed by branches from the deep palmar, radial or median arteries. This explains why even with significant lacerations to the ulna artery a hand can be well perfused.

25. c.      Mucoid cyst.

This is a common lesion that arises from the osteoarthritic DIP joint. There is usually a disruption of the joint and a cyst develops. They cause deformity of the nail because of pressure on the germinal matrix. If they are large it may be necessary to perform a local flap at excision ( transposition ).

26. a.      Nerve stimulation therapy.

If symptoms are not severe and there is not significant and progressive neuropathy then non-operative management must be considered. This includes splintage, hand therapy, steroid injection and even yoga has been proven to be beneficial. Alternatively a patient could be referred for either open or endoscopic release.

27. c.      Scaphoid extension.

In rheumatoid arthritis the inflammation of the synovium sets off a sequence of events that start with correctable deformity and eventually lead to fixed deformity and destruction of the joints. The synovitis at the DRUJ leads to capsular stretching with ECU subluxation and stretching of the dorsal structures. There is erosion of the radio-scapho-capitate ligament with flexion of the scaphoid. The carpus supinates as it moves in an ulna direction. Rather than the ulna becoming prominent it is the carpus that slips away from it.

28. e.      Nail patella syndrome.

This syndrome is a result of an abnormality on chromosome 9. Patients may have subluxed or dislocated radial heads and never realize they have a problem until they have an X-ray. The syndrome can include abnormalities of the patella and nail growth, generalized ligamentous laxity and bony exostoses.

29. d.      50%.

Because of the morbidity and prolonged rehabilitation associated with tendon repair it is advisable to repair lacerations over 50% of the tendon width. The exception to this rule is if there is visible triggering under a local anaesthetic block it may be necessary to address this.

30. b.      Sonic hedgehog protein.

Eight weeks after fertilization, all limb structures are present. It is between 4 and 8 weeks where the majority of congenital disorders in the hand occur. There are many factors involved in limb development; however, there are three key zones responsible for proximodistal, anteroposterior and dorsoventral development. These are the apical ectodermal ridge, zone of polarizing activity and Wnt pathway respectively. These in turn produce fibroblast growth factors, sonic hedgehog protein and LMX1, which all work in a coordinated manner to ensure the normal development of the limb.

EMQs

1. 1. c. Extensor carpi ulnaris (ECU) subluxation and tenosynovitis.
2. f. Vaughn–Jackson syndrome. 3. a. De Quervain’s disease.

This question is really a test of the seven extensor compartments. Each compartment has its own unique anatomy and pathology in turn. Rowers and drummers have ECU subluxation and tenosynovitis. It is common for young mothers to develop tenosynovitis of the first extensor compartment but the condition is not exclusive to them. Vaughn-Jackson syndrome is the attritional rupture of the extensor digiti minimi (EDM) in rheumatoid arthritis. The compartments are as follows:

First – abductor pollicis longus and extensor pollicis brevis tendons

Second – extensor carpi radialis longus and extensor carpi radialis brevis tendons

Third – extensor pollicis longus tendon

Fourth – three tendons of extensor digitorum muscle and the extensor indicis tendon

Fifth – extensor digiti minimi tendon Sixth – extensor carpi ulnaris

2. 1. g. Eikenella corrodens. 2. d. Herpes simplex virus type 1. 3. h. Pasteurella multocida.

The most common cause of hand infections is probably still Staphylococcus aureus. However, because the hands come into contact with specific things it is important to recognize a few important infections. A ‘fight bite’ often presents with a small wound and a history of punching. Eikenella corrodens comes from the human mouth. Dentists and healthcare workers are exposed to the herpes virus. The typical organism in cat bites is Pasteurella. The organisms in necrotizing fasciitis are multiple and usually include clostridia and Group A b- streptococci.

3. 1. f. V-Y plasty (advancement). 2. a. Cross finger flap. 3. c. Terminalization.

Knowing the plastic surgery reconstructive ladder is essential for the management of fingertip injuries. The principle is that if the wound is <1 cm and if there is no bone exposed it can probably heal on its own or be covered with skin only. If there is a bigger lesion with exposed bone then the type of lesion and location must be carefully assessed.

4. 1. c. Epithelioid. 2. g. Enchondroma. 3. e. Schwannoma.

Sarcoma and other malignancies in the hands are rare. Benign tumours and skin cancers are not. Prior to and after the excision of any lesion from the hand the surgeon must have a wide differential diagnosis at hand.

5. 1. f. Psoriasis. 2. b. Scleroderma. 3. e. Amyloidosis.

Many systemic conditions manifest in a pathognomonic manner in the hands. Certain key facts have been provided about each of the conditions. The reader is reminded that other arthritides must be considered in hand pathology.

6. 1. a. Parsonage–Turner syndrome. 2. e. Anterior interosseous nerve palsy.
   3. h. Mannerfelt–Norman syndrome.

The various compression neuropathies can be a bit tricky. The key to the anterior interosseous nerve is that it is a pure motor palsy. Pronator syndrome is a sensory deficit. Mannerfelt–Norman syndrome refers to an attrition rupture of the flexor pollicis longus due to scaphotrapezial synovitis. This question could also be asked in terms of special investigations and special tests in clinical examination.

7. 1. d. Radial shortening. 2. e. Proximal row carpectomy. 3. a. Wrist fusion.

The clues of dorsal wrist pain and Lichtman classification lead the reader to Kienbock’s disease. The question is a discriminator between treatment and salvage of the disease as well as differentiating fixed and mobile deformity (3A vs. 3 B ).

8. 1. a. Intrinsic plus hand. 2. f. Quadrigia effect. 3. b. Boutonnière deformity.

This questions tests knowledge of special signs. Intrinsic tightness as shown by the Bunell test must be differentiated from the intrinsic minus hand, e.g. loss of ulnar nerve function. A Boutonnière deformity is usually due to central slip rupture while a swan neck deformity can have many causes.

9. 1. b. Hamate hook fracture. 2. g. Ulnocarpal abutment. 3. k. Scaphoid lunate advanced collapse.

When evaluating wrist pain it is worth dividing it into dorsal, radial and ulnar-sided wrist pain. Once age and location has been taken into account the diagnosis will be narrowed down. At this stage radiographs and diagnostic injections will probably provide a definite answer. The ring sign is one of many signs that reveal widening of the scapholunate ligament and flexion of the scaphoid.

10. 1. b. Radio-scapholunate fusion. 2. c. Scaphoidectomy and four-corner fusion.
    3. a. Wrist fusion with AO fusion plate.

The aim of this question is to differentiate localized arthritis of the wrist (requiring limited arthrodesis) from pan-arthritis (requiring full fusion). Because of the capitate erosion a proximal row carpectomy is not an option and the four-corner fusion is the correct choice. In a stage IV wrist, full wrist arthrodesis is the only option.

11. 1. d. Ulnar hammer syndrome. 2. g. Raynaud’s disease. 3. c. Raynaud’s phenomenon.

The key to this question is the ability to differentiate Raynaud’s phenomenon from disease. Disease mainly affects females over a chronic period with normal lab tests. The phenomenon is a consequence of either vaso-spastic or vaso-occlusive disease. The ulnar hammer syndrome with thrombosis of the ulnar artery occurs more commonly in males around the age of 55 who smoke, and who use their hand as a hammer. The carpenter fact and the cold sensitivity are the clues.

12. 1. f. Arterial thoracic outlet syndrome. 2. d. Venous thoracic outlet syndrome.
    3. c. Disputed thoracic outlet syndrome.

Thoracic outlet syndrome is a rare condition with 95% being the disputed type with normal special tests. Cervical ribs and true arterial occlusion (i.e. secondary Raynaud’s phenomenon) is a rare cause. Muscular men tend to get venous occlusion. True neurogenic thoracic outlet syndrome is very rare secondary to nerve compression at C8/T1.

13. 1. d. Posterior interosseous nerve palsy. 2. a. Metacarpophalangeal joint ( MCPJ ) subluxation. 3. f. Tendon subluxation.

There are four reasons for a loss of finger extension in rheumatoid arthritis. In simple tendon rupture (Vaughn-Jackson syndrome vs. Jackson Pollock, who is an abstract artist) the tenodesis test will be negative. In subluxation, tenodesis test is positive. If there is a lot of inflammation at the elbow then the posterior interosseous nerve will be compromised, hence the widespread weakness involving the thumb. Lastly, MCPJ misalignment will create a problem with the pull of the tendon and hence a loss of extension. Intrinsic musculature is usually tight, not deficient.

14. 1. c. Pronator teres to extensor carpi radialis longus. 2. h. Extensor indicis to extensor pollicis longus. 3. a. Zancolli’s lasso procedure.

There are many classic and other more creative tendon transfers. It is important to know at least two transfers for each of the major upper limb nerves and understand the principles of tendon transfer. It is the rare attritional rupture of the extensor pollicis longus tendon on Lister’s tubercle that occurs in non-operatively treated fractures. The split flexor pollicis longus to extensor pollicis longus transfer-tenodesis is reserved for more complex reconstruction of pinch, in intrinsic deficiency.

15. 1. b. Hueston’s tabletop test. 2. c. Watson’s shift test. 3. f. Bunnell test.

Special tests must not only be applied to each lesion but the reader must have an understanding of the mechanism for each test. These are but a few of the more common ones and it is recommended that they are all performed even on the normal hand to get into the habit of performing these sometimes difficult tests.