Menu

7. Hand and Wrist MCQs

Practice Set 252 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 5021

Topic: 7. Hand and Wrist

Following a Zone II flexor tendon repair, preventing adhesions while protecting the integrity of the repair is paramount. Which of the following rehabilitation protocols utilizes early true active flexion to achieve this?

. Kleinert protocol
. Modified Duran protocol
. Indiana (Strickland) protocol
. Washington protocol
. Immediate unresisted full active range of motion without splinting

Correct Answer & Explanation

. Indiana (Strickland) protocol

Explanation

The Indiana (or Strickland) protocol is an early active motion protocol for flexor tendon repairs. It utilizes a tenodesis splint that allows the wrist to hinge into slight extension, facilitating early active flexion of the fingers to decrease tendon gliding resistance and prevent adhesions. The Kleinert protocol uses active extension with rubber band-assisted passive flexion. The Duran protocol focuses strictly on passive flexion and extension.

Question 5022

Topic: 7. Hand and Wrist

In a patient presenting with classic symptoms of Carpal Tunnel Syndrome, electromyography (EMG) and nerve conduction studies (NCS) are ordered for confirmation and severity staging. Which of the following electrodiagnostic findings is typically the earliest indicator of median nerve compression at the wrist?

. Increased sensory distal latency (decreased conduction velocity)
. Decreased motor amplitude
. Increased motor latency
. Fibrillation potentials in the abductor pollicis brevis
. Decreased sensory amplitude

Correct Answer & Explanation

. Increased sensory distal latency (decreased conduction velocity)

Explanation

Nerve conduction studies detect demyelination early in the disease process. The sensory fibers are typically affected before the motor fibers in compressive neuropathies like Carpal Tunnel Syndrome. Therefore, an increased sensory distal latency (which corresponds to a decreased sensory nerve conduction velocity) is the earliest detectable electrodiagnostic abnormality. Motor latencies increase later, and amplitude changes or fibrillations (EMG findings) indicate advanced disease with axonal loss.

Question 5023

Topic: 7. Hand and Wrist

In severe carpal tunnel syndrome, sensation over the thenar eminence is typically spared. This occurs because the palmar cutaneous branch of the median nerve arises at which anatomical location?

. Within the carpal tunnel deep to the transverse carpal ligament
. Distal to the transverse carpal ligament, arising from the recurrent motor branch
. Roughly 5-6 cm proximal to the transverse carpal ligament, traveling superficial to it
. From the ulnar nerve in the distal forearm via a Martin-Gruber anastomosis
. From the radial sensory nerve crossing over the flexor carpi radialis tendon

Correct Answer & Explanation

. Roughly 5-6 cm proximal to the transverse carpal ligament, traveling superficial to it

Explanation

The palmar cutaneous branch of the median nerve arises approximately 5 to 6 cm proximal to the transverse carpal ligament and travels superficial to the flexor retinaculum between the flexor carpi radialis (FCR) and palmaris longus tendons to supply sensation to the base of the palm (thenar eminence). Thus, it escapes compression in carpal tunnel syndrome.

Question 5024

Topic: 7. Hand and Wrist

Following a displaced distal radius fracture, the lateral radiograph reveals that the lunate is tilted dorsally relative to the radius, and the scaphoid is flexed volarly. The scapholunate angle is measured at 75 degrees. Which of the following carpal instability patterns does this represent?

. Dorsal Intercalated Segment Instability (DISI)
. Volar Intercalated Segment Instability (VISI)
. Ulnar translocation
. Perilunate dislocation
. Midcarpal instability

Correct Answer & Explanation

. Dorsal Intercalated Segment Instability (DISI)

Explanation

A scapholunate angle > 60 degrees (typically > 70 in frank pathology) with the lunate extended (tilted dorsally) relative to the radius and the scaphoid flexed (tilted volarly) is the hallmark of Dorsal Intercalated Segment Instability (DISI), commonly resulting from scapholunate ligament disruption.

Question 5025

Topic: 7. Hand and Wrist
A 28-year-old carpenter sustains a laceration to his volar index finger at the level of the proximal phalanx, transecting both the FDS and FDP tendons. This injury falls into which flexor tendon zone?
. Zone I
. Zone II
. Zone III
. Zone IV
. Zone V

Correct Answer & Explanation

. Zone II

Explanation

Zone II (historically called 'no man's land') extends from the proximal edge of the A1 pulley to the insertion of the Flexor Digitorum Superficialis (FDS). Injuries here involve both FDS and FDP within the tight fibro-osseous sheath, complicating repair and rehabilitation.

Question 5026

Topic: 7. Hand and Wrist

Guyon's canal serves as the passageway for the ulnar nerve and artery into the hand. What structure forms the floor of this canal?

. Volar carpal ligament
. Transverse carpal ligament (flexor retinaculum)
. Pisohamate ligament
. Hook of the hamate
. Palmaris brevis muscle

Correct Answer & Explanation

. Transverse carpal ligament (flexor retinaculum)

Explanation

The floor of Guyon's canal is formed by the transverse carpal ligament (flexor retinaculum) and the pisohamate ligament. The roof is the volar carpal ligament. The medial border is the pisiform, and the lateral border is the hook of the hamate.

Question 5027

Topic: 7. Hand and Wrist

A 45-year-old female presents with numbness and tingling in her thumb, index, and long fingers. Examination reveals weakness in thumb opposition but normal sensation over the thenar eminence. Which of the following anatomical structures is most directly responsible for the preservation of her thenar sensation?

. Recurrent motor branch of the median nerve
. Palmar cutaneous branch of the median nerve
. Superficial branch of the radial nerve
. Anterior interosseous nerve
. Deep branch of the ulnar nerve

Correct Answer & Explanation

. Palmar cutaneous branch of the median nerve

Explanation

The palmar cutaneous branch of the median nerve branches off proximal to the carpal tunnel and travels superficial to the transverse carpal ligament. Therefore, it is spared in carpal tunnel syndrome, preserving sensation over the thenar eminence.

Question 5028

Topic: 7. Hand and Wrist

A 25-year-old male falls onto an outstretched hand and sustains a proximal pole scaphoid fracture. Which specific artery is the primary contributor to the retrograde blood supply of the scaphoid, predisposing this fracture pattern to avascular necrosis?

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

Correct Answer & Explanation

. Dorsal carpal branch of the radial artery

Explanation

The dorsal carpal branch of the radial artery supplies 70-80% of the scaphoid, entering distally and perfusing the bone in a retrograde fashion. Proximal pole fractures disrupt this vascular flow, creating a high risk of avascular necrosis.

Question 5029

Topic: 7. Hand and Wrist

A 24-year-old male sustains a proximal pole scaphoid fracture. He is at high risk for avascular necrosis or nonunion. This risk is primarily due to the retrograde intraosseous blood supply of the scaphoid. Which vessel provides the dominant blood supply to the proximal pole of the scaphoid?

. Volar carpal branch of the radial artery
. Dorsal carpal branch of the radial artery
. Deep palmar arch
. Ulnar artery via the recurrent interosseous
. Anterior interosseous artery

Correct Answer & Explanation

. Dorsal carpal branch of the radial artery

Explanation

The scaphoid receives 70-80% of its blood supply from the dorsal carpal branch of the radial artery. This vessel enters the scaphoid at the dorsal ridge (distal to the waist) and provides a retrograde intraosseous supply to the proximal pole. Because of this retrograde flow, fractures at the waist or proximal pole disrupt blood flow to the proximal fragment, leading to high rates of avascular necrosis and nonunion.

Question 5030

Topic: 7. Hand and Wrist

Within 'Zone II' of the flexor tendon system in the hand, the flexor tendons rely on a dual blood supply consisting of diffusion from synovial fluid and perfusion from a segmental vascular system. What structures carry this direct segmental blood supply to the flexor tendons within the digital sheath?

. The common digital arteries
. The proper digital arteries
. The vincula brevia and longa
. The lumbrical muscle bellies
. The A2 and A4 pulleys

Correct Answer & Explanation

. The vincula brevia and longa

Explanation

In the hand, flexor tendons within the digital sheaths (particularly Zone II, 'No Man\'s Land') receive their intrinsic vascular supply via specialized folds of mesotenon called the vincula. There are vincula brevia and longa for both the FDS and FDP tendons. These structures carry small branches from the digital arteries to supply the dorsal aspect of the tendons.

Question 5031

Topic: 7. Hand and Wrist

A 65-year-old female undergoes open reduction and internal fixation of a distal radius fracture using a volar locking plate. If the plate is positioned too far distally, extending past the 'watershed line' of the distal radius, she is at the highest risk for which of the following postoperative complications?

. Extensor pollicis longus (EPL) tendon rupture
. Flexor pollicis longus (FPL) tendon rupture
. Median nerve compression (carpal tunnel syndrome)
. Avascular necrosis of the lunate
. Ulnar impaction syndrome

Correct Answer & Explanation

. Flexor pollicis longus (FPL) tendon rupture

Explanation

The 'watershed line' is a bony prominence on the volar aspect of the distal radius. If a volar locking plate is placed distal to this line, the implant will sit proud against the flexor tendons. The flexor pollicis longus (FPL) tendon lies directly over this area and is subjected to mechanical attrition and fraying against the hard hardware edge, significantly increasing the risk of delayed FPL rupture. (EPL rupture is more associated with dorsal screw penetration).

Question 5032

Topic: Wrist & Carpus

In a prospective randomized clinical trial comparing two fixation methods for distal radius fractures, the researchers conclude there is no significant difference between the two treatments. However, a true difference actually exists in the population. Which of the following statistical errors has occurred, and what parameter quantifies its probability?

. Type I error; quantified by Alpha
. Type I error; quantified by Beta
. Type II error; quantified by Alpha
. Type II error; quantified by Beta
. Type II error; quantified by 1 - Beta (Power)

Correct Answer & Explanation

. Type II error; quantified by Beta

Explanation

A Type II error occurs when researchers fail to reject a false null hypothesis (i.e., failing to find a difference that actually exists). The probability of committing a Type II error is denoted by beta. Power (1 - beta) is the probability of correctly rejecting the null hypothesis when a true difference exists. A Type I error (alpha) is finding a difference when none exists.

Question 5033

Topic: 7. Hand and Wrist
A 35-year-old male manual laborer presents with chronic, worsening dorsal wrist pain. Radiographs reveal sclerosis and fragmentation of the lunate, along with a fixed scaphoid rotary subluxation (ring sign). Ulnar variance is neutral. What is the most appropriate surgical treatment for this patient?
. Radial shortening osteotomy
. Proximal row carpectomy
. Ulnar shortening osteotomy
. Carpal tunnel release
. Core decompression of the lunate

Correct Answer & Explanation

. Proximal row carpectomy

Explanation

This patient has Stage IIIb Kienbock's disease, characterized by lunate collapse/fragmentation and a fixed scaphoid rotary subluxation. Joint-leveling procedures (like radial shortening) are indicated for earlier stages (I, II, IIIa) in patients with ulnar negative variance. Stage IIIb with a fixed scaphoid deformity is best treated with salvage procedures such as proximal row carpectomy (PRC) or scaphoid-trapezium-trapezoid (STT) fusion.

Question 5034

Topic: Nerve & Tendon
A rugby player sustains a closed avulsion of the flexor digitorum profundus (FDP) of the ring finger. Physical exam and ultrasound reveal the tendon has retracted completely into the palm. According to the Leddy-Packer classification, what type of injury is this?
. Type I
. Type II
. Type III
. Type IV
. Type V

Correct Answer & Explanation

. Type I

Explanation

The Leddy-Packer classification describes FDP avulsion injuries (Jersey finger). Type I involves retraction into the palm (blood supply from the vincula is completely disrupted, requiring surgery within 7-10 days to avoid tendon necrosis and contracture). Type II retracts to the PIP joint (held by the long vinculum). Type III involves a large bony fragment that catches at the A4 pulley. Type IV includes a bony fragment and simultaneous avulsion of the tendon off the fragment.

Question 5035

Topic: 7. Hand and Wrist

A 45-year-old typist complains of numbness and tingling in the thumb, index, and middle fingers. Symptoms are worst at night. Electromyography and Nerve Conduction Studies (EMG/NCS) are ordered. What is typically the earliest and most sensitive electrodiagnostic finding in Carpal Tunnel Syndrome?

. Increased distal motor latency
. Decreased motor amplitude
. Increased distal sensory latency
. Fibrillation potentials in the abductor pollicis brevis
. Prolonged F-wave latency

Correct Answer & Explanation

. Increased distal sensory latency

Explanation

In compressive neuropathies like early Carpal Tunnel Syndrome, the large myelinated sensory fibers are typically affected before the motor fibers. Therefore, the earliest and most sensitive electrodiagnostic finding on nerve conduction studies is a prolonged (increased) distal sensory latency of the median nerve across the carpal tunnel.

Question 5036

Topic: 7. Hand and Wrist

A 35-year-old male falls onto an outstretched hand and presents with severe wrist pain and swelling. Lateral radiographs show the capitate dislocated dorsally relative to the lunate, which remains aligned with the radius. The scaphoid and triquetrum are displaced with the capitate. Which of the following is the most appropriate initial management step?

. Immediate open reduction and internal fixation of the carpus
. Urgent closed reduction and application of a sugar-tong splint
. Referral for MRI to assess ligamentous injury
. CT scan to evaluate for associated fracture fragments
. Extended-wrist immobilization with a cast for 6 weeks

Correct Answer & Explanation

. Urgent closed reduction and application of a sugar-tong splint

Explanation

The description 'capitate dislocated dorsally relative to the lunate, which remains aligned with the radius' is pathognomonic for a perilunate dislocation. This is a severe, high-energy injury representing a continuum of carpal instability (often involving a trans-scaphoid component). It requires urgent closed reduction, typically under conscious sedation or general anesthesia, to restore carpal alignment, decompress neurovascular structures (especially the median nerve), and prevent chronic stiffness or avascular necrosis of the lunate. While an MRI or CT might be needed later for detailed planning of definitive surgical stabilization, theinitialand most critical step is reduction. Open reduction and internal fixation (ORIF) is usually requiredaftersuccessful closed reduction for definitive stabilization, but not as the immediate first step unless closed reduction fails. Immobilization alone is insufficient.

Question 5037

Topic: 7. Hand and Wrist

A 28-year-old male presents with wrist pain 2 years after a fall. Imaging reveals a scaphoid nonunion with early radiocarpal arthrosis. The midcarpal joint is spared. What is the most appropriate surgical procedure?

. Scaphoid open reduction and vascularized bone grafting
. Proximal row carpectomy (PRC)
. Total wrist arthrodesis
. Scaphoid excision and volar capsulodesis
. Radial styloidectomy alone

Correct Answer & Explanation

. Proximal row carpectomy (PRC)

Explanation

The patient has a SNAC (Scaphoid Nonunion Advanced Collapse) Stage II wrist (radiocarpal arthrosis with preserved midcarpal joint). Proximal row carpectomy or four-corner fusion are both appropriate; bone grafting is contraindicated once arthrosis develops.

Question 5038

Topic: 7. Hand and Wrist

A 30-year-old carpenter sustains a laceration to the volar aspect of his index finger at the level of the proximal phalanx (Zone II). Examination reveals an inability to flex the DIP and PIP joints. What is the most appropriate surgical approach for repair?

. Primary repair with a 2-strand core suture and no epitendinous repair
. Primary repair using a 4-strand or 6-strand core suture with an epitendinous suture
. Tendon grafting using the palmaris longus
. Tenodesis of the FDP to the middle phalanx
. Delayed primary repair after 4 weeks of wound healing

Correct Answer & Explanation

. Primary repair using a 4-strand or 6-strand core suture with an epitendinous suture

Explanation

Zone II flexor tendon injuries require robust repair to allow early active motion protocols, which prevent adhesions. A multi-strand (4- or 6-strand) core suture combined with an epitendinous repair provides the necessary tensile strength for early mobilization.

Question 5039

Topic: Wrist & Carpus

A 40-year-old female presents after a fall on an outstretched hand. Radiographs reveal a fracture of the volar lip of the distal radius with volar subluxation of the carpus. Which of the following is the most appropriate definitive management?

. Closed reduction and long-arm cast in flexion
. Closed reduction and short-arm cast in extension
. Volar buttress plating
. Dorsal spanning plate
. External fixation with distraction

Correct Answer & Explanation

. Volar buttress plating

Explanation

A Volar Barton fracture is an intra-articular shear fracture of the distal radius with associated volar radiocarpal subluxation. It is inherently unstable and is best managed with open reduction and internal fixation using a volar buttress plate to counteract the volar shear forces.

Question 5040

Topic: 7. Hand and Wrist
A 25-year-old sustains a volar laceration to the index finger at the level of the proximal phalanx, transecting both the FDP and FDS tendons. This injury corresponds to which flexor tendon zone?
. Zone I
. Zone II
. Zone III
. Zone IV
. Zone V

Correct Answer & Explanation

. Zone II

Explanation

Zone II extends from the proximal aspect of the A1 pulley to the insertion of the FDS on the middle phalanx. It is historically known as "no man's land" due to poor healing and dense adhesions when both tendons are injured within the fibro-osseous sheath.

Test Yourself

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

On this Page