Menu

7. Hand and Wrist MCQs

Practice Set 223 of 266

This practice set contains high-yield board review questions covering key concepts in 7. Hand and Wrist. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 4441

Topic: 7. Hand and Wrist

A 25-year-old carpenter sustains a clean laceration to the volar middle phalanx of his index finger, dividing both the flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) tendons (Zone II). Primary repair is performed. Which of the following postoperative rehabilitation principles yields the best outcomes for minimizing adhesions while preventing rupture?

. Immediate active flexion and active extension without splinting
. Six weeks of static immobilization followed by active range of motion
. Early controlled active extension and passive flexion (e.g., Duran or Kleinert protocol)
. Early active extension combined with heavy resisted active flexion
. Immediate passive extension and passive flexion only

Correct Answer & Explanation

. Immediate active flexion and active extension without splinting

Explanation

Zone II flexor tendon repairs occur in "no man's land" where the FDS and FDP travel within a tight fibro-osseous sheath. Historically, strict immobilization led to dense adhesions and poor function. Current standards involve early controlled motion protocols. The classic protocols (Duran, Kleinert) use active extension and passive flexion to glide the tendons within the sheath without placing excessive active tension that could rupture the repair. (Note: Modern early active motion protocols exist but involve careful place-and-hold techniques, not "heavy resisted" flexion).

Question 4442

Topic: Wrist & Carpus

A 55-year-old female who underwent open reduction and internal fixation of a distal radius fracture with a volar locking plate 9 months ago presents with a sudden inability to flex the interphalangeal (IP) joint of her thumb. Which of the following technical errors during the initial surgery is the most likely cause of this complication?

. Placement of the volar plate distal to the watershed line
. Over-penetration of screws through the dorsal cortex
. Failure to repair the pronator quadratus muscle over the plate
. Placement of the plate too proximal on the radial diaphysis
. Excessive radial inclination of the plate

Correct Answer & Explanation

. Placement of the volar plate distal to the watershed line

Explanation

The patient has sustained an iatrogenic rupture of the Flexor Pollicis Longus (FPL) tendon, which is a known complication of volar plating for distal radius fractures. The "watershed line" is a transverse ridge on the volar distal radius, marking the distal margin of the pronator fossa. If a plate is placed distal to this line, it sits prominently and rubs against the overlying flexor tendons (most commonly the FPL), leading to tenosynovitis, attrition, and eventual rupture. Dorsal screw over-penetration endangers the extensor tendons (e.g., EPL).

Question 4443

Topic: 7. Hand and Wrist

A 24-year-old male presents with persistent radial-sided wrist pain 8 months after a fall. Imaging reveals a scaphoid proximal pole nonunion with humpback deformity. MRI confirms avascular necrosis of the proximal pole fragment. Which of the following graft options is most appropriate?

. 1,2 Intercompartmental supraretinacular artery (1,2 ICSRA) graft
. Free medial femoral condyle (MFC) vascularized bone graft
. Volar carpal artery pedicled graft
. Pronator quadratus pedicled bone graft
. Non-vascularized iliac crest bone graft

Correct Answer & Explanation

. 1,2 Intercompartmental supraretinacular artery (1,2 ICSRA) graft

Explanation

A free medial femoral condyle (MFC) vascularized bone graft provides robust blood supply and structural support. It is the treatment of choice for scaphoid proximal pole nonunions complicated by both avascular necrosis and a humpback deformity requiring structural correction.

Question 4444

Topic: Nerve & Tendon
A 28-year-old carpenter sustains a deep volar laceration to his right index finger exactly at the level of the distal interphalangeal (DIP) joint crease. Examination shows inability to flex the DIP joint, but proximal interphalangeal (PIP) joint flexion remains intact against resistance. This injury corresponds to which flexor tendon zone?
. Zone I
. Zone II
. Zone III
. Zone IV
. Zone V

Correct Answer & Explanation

. Zone I

Explanation

Zone I flexor tendon injuries occur distal to the insertion of the flexor digitorum superficialis (FDS). These injuries involve isolated transection of the flexor digitorum profundus (FDP), resulting in loss of DIP flexion while PIP flexion is spared.

Question 4445

Topic: Nerve & Tendon

A 6-year-old girl falls off monkey bars and sustains a significantly displaced extension-type supracondylar humerus fracture. On examination, she is unable to flex the interphalangeal joint of her thumb and the distal interphalangeal joint of her index finger. Which nerve is most likely injured?

. Radial nerve
. Ulnar nerve
. Anterior interosseous nerve
. Posterior interosseous nerve
. Musculocutaneous nerve

Correct Answer & Explanation

. Radial nerve

Explanation

The anterior interosseous nerve (AIN), a branch of the median nerve, is the most commonly injured nerve in extension-type supracondylar humerus fractures. It innervates the flexor pollicis longus and the flexor digitorum profundus to the index and long fingers.

Question 4446

Topic: 7. Hand and Wrist

A 45-year-old female with severe, refractory carpal tunnel syndrome undergoes an open carpal tunnel release. During the procedure, the surgeon inadvertently cuts the transverse carpal ligament too far radially. Which anatomical structure is at greatest risk of iatrogenic injury?

. Superficial palmar arch
. Median nerve proper
. Ulnar artery
. Recurrent motor branch of the median nerve
. Deep branch of the ulnar nerve

Correct Answer & Explanation

. Superficial palmar arch

Explanation

The recurrent motor branch of the median nerve supplies the thenar muscles and typically branches off the radial aspect of the median nerve. Dividing the ligament too far radially places this critical motor branch at high risk.

Question 4447

Topic: 7. Hand and Wrist

A 25-year-old male falls on an outstretched hand and sustains a displaced fracture through the proximal pole of the scaphoid. This specific fracture pattern carries a notoriously high risk of nonunion and avascular necrosis. This complication is primarily due to the dominant intraosseous blood supply flowing in which direction?

. Proximal to distal via the volar carpal branch
. Volar to dorsal via the radial artery
. Distal to proximal via the dorsal carpal branch
. Medial to lateral via the ulnar artery
. Directly into the proximal pole via the scapholunate interosseous ligament

Correct Answer & Explanation

. Proximal to distal via the volar carpal branch

Explanation

The scaphoid receives 70-80% of its blood supply from the dorsal carpal branch of the radial artery, which enters at the dorsal ridge and flows retrogradely (distal to proximal). Proximal pole fractures disrupt this retrograde flow, heavily predisposing the fragment to ischemia.

Question 4448

Topic: Hand Trauma & Infection

A 40-year-old diabetic male presents with an exquisitely tender, swollen index finger held in slight flexion. Passive extension of the digit elicits extreme pain extending into the palm. What is the most appropriate next step in management?

. Oral antibiotics and outpatient physical therapy
. Splinting, NSAIDs, and elevation
. Urgent incision and drainage with intravenous antibiotics
. Corticosteroid injection into the flexor sheath
. EMG and nerve conduction studies

Correct Answer & Explanation

. Oral antibiotics and outpatient physical therapy

Explanation

This presentation describes Kanavel's cardinal signs of acute pyogenic flexor tenosynovitis. This is an orthopedic surgical emergency requiring prompt incision, irrigation, drainage, and broad-spectrum IV antibiotics to prevent tendon necrosis.

Question 4449

Topic: 7. Hand and Wrist

A 25-year-old falls on an outstretched hand, sustaining a minimally displaced scaphoid proximal pole fracture. Which artery provides the primary blood supply to this specific region of the scaphoid?

. Superficial palmar arch
. Deep palmar arch
. Ulnar artery
. Dorsal carpal branch of the radial artery
. Anterior interosseous artery

Correct Answer & Explanation

. Superficial palmar arch

Explanation

The primary blood supply to the scaphoid is derived from the dorsal carpal branch of the radial artery, which enters the bone distally and flows in a retrograde fashion. This unique vascular anatomy places proximal pole fractures at extremely high risk for avascular necrosis and nonunion.

Question 4450

Topic: 7. Hand and Wrist

A 35-year-old male sustains a displaced fracture of the scaphoid waist. Which of the following blood vessels provides the primary retrograde blood supply to the proximal pole of the scaphoid?

. Palmar carpal branch of the radial artery
. Dorsal carpal branch of the radial artery
. Superficial palmar arch
. Deep palmar arch
. Ulnar artery

Correct Answer & Explanation

. Palmar carpal branch of the radial artery

Explanation

The dorsal carpal branch of the radial artery enters the scaphoid at the distal pole and provides retrograde blood flow to the proximal pole. This retrograde supply explains the high rate of avascular necrosis seen in proximal scaphoid fractures.

Question 4451

Topic: 7. Hand and Wrist
In the context of flexor tendon repairs in the hand, which zone is historically referred to as "No Man's Land" due to the high risk of adhesion formation and historically poor surgical outcomes?
. Zone I
. Zone II
. Zone III
. Zone IV
. Zone V

Correct Answer & Explanation

. Zone II

Explanation

Zone II extends from the proximal edge of the A1 pulley to the insertion of the FDS tendon. It is known as "No Man's Land" because both the FDS and FDP tendons run tightly within a single fibro-osseous sheath, making repairs highly prone to restrictive adhesions.

Question 4452

Topic: Wrist & Carpus

A 60-year-old woman is treated non-operatively in a cast for a minimally displaced Colles fracture. Six weeks later, after cast removal, she suddenly loses the ability to actively extend her thumb interphalangeal joint. What is the most appropriate definitive management for this complication?

. Extensor indicis proprius (EIP) to extensor pollicis longus (EPL) tendon transfer
. Primary end-to-end repair of the EPL tendon
. Tendon graft using the palmaris longus
. Immobilization in a thumb spica splint for 6 weeks
. Release of the first dorsal compartment

Correct Answer & Explanation

. Extensor indicis proprius (EIP) to extensor pollicis longus (EPL) tendon transfer

Explanation

Spontaneous rupture of the EPL tendon post-distal radius fracture is due to ischemia or attrition over Lister's tubercle. Because the tendon ends retract and degenerate, primary repair is usually impossible, making an EIP to EPL transfer the gold standard.

Question 4453

Topic: Hand Trauma & Infection

A 35-year-old construction worker presents with a swollen, painful index finger 3 days after a puncture wound. Which of the following represents the four classic Kanavel signs of pyogenic flexor tenosynovitis?

. Flexed resting posture, fusiform swelling, pain on passive extension, tenderness along the flexor sheath
. Extended resting posture, localized fluctuance, pain on active flexion, erythema
. Flexed resting posture, crepitus on motion, numbness of the fingertip, pain on passive flexion
. Dorsal swelling, pain on passive extension, normal resting posture, absent radial pulse
. Fusiform swelling, fluctuance at the DIP joint, pain on active extension, ascending lymphangitis

Correct Answer & Explanation

. Flexed resting posture, fusiform swelling, pain on passive extension, tenderness along the flexor sheath

Explanation

Kanavel's four cardinal signs of flexor tenosynovitis are a flexed resting posture of the digit, fusiform (sausage-like) swelling, exquisite pain on passive extension, and tenderness along the entire course of the flexor tendon sheath.

Question 4454

Topic: Wrist & Carpus
A 55-year-old manual laborer presents with chronic wrist pain. Radiographs reveal advanced scapholunate advanced collapse (SLAC) with degenerative changes involving the radioscaphoid joint and the entire scaphoid facet of the radius, sparing the capitolunate joint. What SLAC stage does this represent?
. Stage I
. Stage II
. Stage III
. Stage IV
. Stage V

Correct Answer & Explanation

. Stage II

Explanation

SLAC Stage II involves osteoarthritis of the entire radioscaphoid joint. Stage III involves the capitolunate joint, and Stage I is limited to the radial styloid-scaphoid articulation.

Question 4455

Topic: 7. Hand and Wrist

A 65-year-old woman undergoes volar locked plating for a displaced distal radius fracture. Six months later, she is unable to actively flex the interphalangeal joint of her thumb. What is the most likely cause of this complication?

. Rupture of the flexor pollicis longus (FPL) tendon
. Avulsion of the flexor digitorum profundus
. Median nerve compression in the carpal tunnel
. Unrecognized anterior interosseous nerve (AIN) palsy
. Extensor pollicis longus (EPL) rupture

Correct Answer & Explanation

. Rupture of the flexor pollicis longus (FPL) tendon

Explanation

Placement of a volar plate distal to the watershed line of the distal radius can cause attrition and subsequent rupture of the Flexor Pollicis Longus (FPL) tendon. This presents as a delayed inability to actively flex the thumb IP joint.

Question 4456

Topic: 7. Hand and Wrist

A 22-year-old snowboarder sustains a proximal pole scaphoid fracture. The high risk of avascular necrosis in this fracture pattern is primarily due to the anatomy of its blood supply, which is derived mostly from the:

. Volar carpal branch of the radial artery
. Dorsal carpal branch of the radial artery
. Superficial palmar arch
. Deep palmar arch
. Ulnar artery via the interosseous membrane

Correct Answer & Explanation

. Volar carpal branch of the radial artery

Explanation

The proximal pole of the scaphoid is susceptible to avascular necrosis because its blood supply enters distally and flows retrogradely. This blood supply is primarily provided by the dorsal carpal branch of the radial artery.

Question 4457

Topic: Nerve & Tendon

A patient presents with Anterior Interosseous Nerve (AIN) syndrome. On physical examination, they are unable to form an "OK" sign. Which of the following muscles is definitively spared in an isolated AIN palsy?

. Flexor pollicis longus
. Flexor digitorum profundus to the index finger
. Pronator quadratus
. Flexor digitorum superficialis
. Flexor digitorum profundus to the middle finger

Correct Answer & Explanation

. Flexor pollicis longus

Explanation

The AIN innervates the flexor pollicis longus, pronator quadratus, and the flexor digitorum profundus to the index and middle fingers. The flexor digitorum superficialis is innervated by the main trunk of the median nerve and is completely spared.

Question 4458

Topic: Nerve & Tendon

A 22-year-old rugby player presents with an inability to flex the distal interphalangeal (DIP) joint of his ring finger. Ultrasound confirms the flexor digitorum profundus (FDP) tendon has retracted into the palm. What is the maximum recommended time frame for primary repair to avoid myotendinous contracture?

. 24 hours
. 7 to 10 days
. 3 to 4 weeks
. 6 weeks
. 12 weeks

Correct Answer & Explanation

. 24 hours

Explanation

This is a Type I Jersey finger (FDP avulsion retracted into the palm), which completely disrupts the vincula. It requires surgical repair within 7 to 10 days before the tendon becomes irreparably contracted and ischemic.

Question 4459

Topic: Wrist & Carpus

A 45-year-old female sustains a non-displaced fracture of the distal radius. Four weeks later, she presents with sudden inability to actively extend the interphalangeal joint of her thumb. Which of the following is the most likely cause of this complication?

. Iatrogenic nerve injury during casting
. Extensor pollicis longus attrition over Lister's tubercle
. Ischemic contracture of the forearm
. Unrecognized rupture of the flexor pollicis longus
. Extensor pollicis brevis entrapment in the first dorsal compartment

Correct Answer & Explanation

. Iatrogenic nerve injury during casting

Explanation

Extensor pollicis longus (EPL) tendon rupture is a known complication of non-displaced distal radius fractures. It typically occurs due to mechanical attrition over the fracture callus at Lister's tubercle or localized ischemia.

Question 4460

Topic: Nerve & Tendon

A 32-year-old male bodybuilder complains of medial elbow pain and an audible, palpable snapping sensation when performing triceps extensions. Examination reveals a 'double snap' over the medial epicondyle as the elbow is moved from extension into flexion. Which two anatomical structures are most likely subluxating over the medial epicondyle?

. Ulnar nerve and medial head of the triceps
. Ulnar nerve and lateral head of the triceps
. Ulnar nerve and common flexor tendon
. Median nerve and medial head of the triceps
. Median nerve and brachialis tendon

Correct Answer & Explanation

. Ulnar nerve and medial head of the triceps

Explanation

Snapping triceps syndrome typically involves the dynamic subluxation of the ulnar nerve followed by the medial head of the triceps over the medial epicondyle during elbow flexion. This creates a distinct 'double snap' on examination. Treatment often requires ulnar nerve transposition and concurrent resection or management of the prominent medial head of the triceps.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page