Menu

7. Hand and Wrist MCQs

Practice Set 85 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 1681

Topic: Nerve & Tendon

A patient is undergoing an Oberlin transfer for a C5-C6 brachial plexus root avulsion to restore elbow flexion. Which specific donor nerve fascicle is most commonly transferred to the motor branch of the biceps?

. Sensory fascicle of the median nerve
. Motor fascicle of the median nerve to the FCR
. Sensory fascicle of the ulnar nerve
. Motor fascicle of the ulnar nerve to the FCU
. Motor fascicle of the radial nerve to the brachioradialis

Correct Answer & Explanation

. Motor fascicle of the ulnar nerve to the FCU

Explanation

The classic Oberlin transfer utilizes an expendable motor fascicle from the ulnar nerve (typically the one innervating the flexor carpi ulnaris) transferred to the motor branch of the biceps to restore elbow flexion in upper trunk injuries.

Question 1682

Topic: 7. Hand and Wrist
A 35-year-old patient presents with severe Stage IIIA Kienböck's disease. Radiographs reveal lunate sclerosis and fragmentation but no fixed carpal collapse, accompanied by an ulnar negative variance of 3 mm. Which of the following is the most appropriate joint-leveling procedure?
. Proximal row carpectomy
. Ulnar shortening osteotomy
. Radial shortening osteotomy
. Capitate shortening osteotomy
. Lunate excision and silicone replacement

Correct Answer & Explanation

. Radial shortening osteotomy

Explanation

In early advanced Kienböck's disease (Stage IIIA) with ulnar negative variance, a radial shortening osteotomy is the preferred joint-leveling procedure to decompress the lunate and halt disease progression.

Question 1683

Topic: 7. Hand and Wrist

In arthroscopic repair of a peripheral triangular fibrocartilage complex (TFCC) tear, which of the following neurological structures is at highest risk of injury when establishing the 6U portal?

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

Correct Answer & Explanation

. Dorsal sensory branch of the ulnar nerve

Explanation

The dorsal sensory branch of the ulnar nerve (DSBUN) courses directly over the ulnar aspect of the wrist. It is highly susceptible to injury during the establishment of the 6U portal or during inside-out TFCC repairs.

Question 1684

Topic: 7. Hand and Wrist
A patient develops a Scaphoid Nonunion Advanced Collapse (SNAC) wrist following an untreated scaphoid fracture. What is the typical sequential progression of degenerative arthritis in a SNAC wrist?
. Radioscaphoid -> Scaphocapitate -> Capitolunate
. Radioscaphoid -> Radiolunate -> Capitolunate
. Scaphocapitate -> Radioscaphoid -> Radiolunate
. Capitolunate -> Scaphocapitate -> Radioscaphoid
. Radioscaphoid -> Capitolunate -> Scaphocapitate

Correct Answer & Explanation

. Radioscaphoid -> Scaphocapitate -> Capitolunate

Explanation

SNAC wrist arthritis reliably progresses in a specific sequence: beginning at the radial styloid-scaphoid articulation (Stage I), advancing to the scaphocapitate joint (Stage II), and finally involving the capitolunate joint (Stage III). The radiolunate joint is typically spared.

Question 1685

Topic: 7. Hand and Wrist

A 40-year-old male sustains a laceration over the proximal phalanx (Zone II), severing both the FDS and FDP tendons. The surgeon attempts a primary repair but inadvertently sutures the lumbrical muscle too tightly during closure. What clinical phenomenon is the patient most likely to exhibit postoperatively?

. Swan neck deformity
. Boutonniere deformity
. Paradoxical PIP joint extension during active finger flexion
. Inability to flex the DIP joint with the PIP joint extended
. Quadriga effect

Correct Answer & Explanation

. Paradoxical PIP joint extension during active finger flexion

Explanation

Suturing the lumbrical too tightly or allowing the FDP to retract proximal to the lumbrical origin creates a 'lumbrical plus' finger. Attempted active flexion of the FDP paradoxically increases tension on the lumbrical, leading to active extension of the PIP and DIP joints.

Question 1686

Topic: Wrist & Carpus

A 65-year-old woman presents 8 weeks after open reduction and internal fixation of a distal radius fracture with a volar locking plate. She suddenly lost the ability to actively extend her thumb interphalangeal joint. Radiographs show prominent screws penetrating the dorsal cortex. What is the most reliable surgical treatment for this complication?

. Primary end-to-end repair of the ruptured tendon
. Extensor indicis proprius (EIP) to extensor pollicis longus (EPL) tendon transfer
. Free tendon graft using the palmaris longus
. Tenodesis of the EPL to the extensor carpi radialis brevis
. Arthrodesis of the thumb interphalangeal joint

Correct Answer & Explanation

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

Explanation

Prominent dorsal screws from volar plating commonly cause attritional rupture of the Extensor Pollicis Longus (EPL) tendon. Primary repair is usually impossible due to retracted, frayed tendon ends; therefore, an EIP to EPL transfer is the gold standard treatment.

Question 1687

Topic: 7. Hand and Wrist

A 24-year-old male presents with profound median nerve palsy. To restore thumb opposition, a Burkhalter transfer is planned utilizing the Extensor Indicis Proprius (EIP). To optimize the vector for thumb pronation and palmar abduction, the transferred EIP tendon should be routed around which anatomical structure to act as a pulley?

. Flexor carpi radialis (FCR) tendon
. Flexor carpi ulnaris (FCU) tendon
. Hook of the hamate
. Ulnar border of the palmar aponeurosis
. Distal edge of the transverse carpal ligament

Correct Answer & Explanation

. Ulnar border of the palmar aponeurosis

Explanation

In an EIP to APB transfer (Burkhalter), routing the tendon around the ulnar border of the palmar aponeurosis (or sometimes the FCU depending on specific modifications, but classically the ulnar border of the palmar fascia) directs the vector of pull from the pisiform area. This optimally restores true thumb opposition.

Question 1688

Topic: 7. Hand and Wrist

A 30-year-old carpenter suffers a deep laceration at the level of the proximal interphalangeal (PIP) joint, transecting the central slip of the extensor tendon. If left untreated, the lateral bands will eventually subluxate. In relation to the axis of rotation of the PIP joint, in which direction do the lateral bands migrate to produce the classic resulting deformity?

. Dorsal to the PIP axis of rotation
. Volar to the PIP axis of rotation
. Proximal to the MCP joint
. Distal to the DIP joint
. Centralized over the middle phalanx

Correct Answer & Explanation

. Volar to the PIP axis of rotation

Explanation

Untreated central slip ruptures lead to a Boutonniere deformity. The lateral bands migrate volar to the axis of rotation of the PIP joint, converting their extensor force into a flexor force at the PIP, while continuing to extend the DIP joint.

Question 1689

Topic: 7. Hand and Wrist
A 45-year-old manual laborer presents with chronic wrist pain. Radiographs reveal advanced scapholunate advanced collapse (SLAC) with arthritic changes involving the radioscaphoid joint and the proximal capitate. The radiolunate joint is entirely spared. Which of the following surgical interventions is most appropriate?
. Proximal row carpectomy (PRC)
. Scaphoid excision and four-corner fusion
. Scapholunate ligament reconstruction
. Total wrist arthrodesis
. Radial styloidectomy

Correct Answer & Explanation

. Scaphoid excision and four-corner fusion

Explanation

This patient has SLAC Stage III wrist arthritis (capitolunate involvement). Proximal row carpectomy is contraindicated when the capitate head is arthritic; therefore, scaphoid excision with a four-corner fusion is the treatment of choice.

Question 1690

Topic: Nerve & Tendon

Six months after a Zone II flexor tendon repair of the middle finger, a patient complains that the affected digit paradoxically extends at the proximal interphalangeal (PIP) joint when attempting to make a tight fist. What is the most likely etiology of this phenomenon?

. Rupture of the central slip
. Adhesion of the flexor digitorum superficialis (FDS) tendon
. Rupture of the flexor digitorum profundus (FDP) repair with proximal retraction
. Attenuation of the volar plate
. Failure of the A2 pulley

Correct Answer & Explanation

. Rupture of the flexor digitorum profundus (FDP) repair with proximal retraction

Explanation

This describes 'lumbrical plus' syndrome, caused by a ruptured or overly long FDP tendon. When the patient attempts to flex, the retracted FDP pulls on the intact lumbrical origin, causing paradoxical PIP extension.

Question 1691

Topic: 7. Hand and Wrist

A 38-year-old cyclist complains of intrinsic hand weakness and numbness strictly affecting the volar aspect of his small finger and the ulnar half of his ring finger. Sensation on the dorsal ulnar aspect of the hand is completely normal. Where is the most likely site of neural compression?

. Cubital tunnel
. Arcade of Struthers
. Guyon's canal (Zone 1)
. Guyon's canal (Zone 2)
. C8 nerve root

Correct Answer & Explanation

. Guyon's canal (Zone 1)

Explanation

Normal dorsal ulnar sensation localizes the lesion distal to the takeoff of the dorsal ulnar cutaneous nerve (which branches proximal to the wrist). A lesion in Zone 1 of Guyon's canal affects both mixed motor and sensory branches to the volar fingers.

Question 1692

Topic: Nerve & Tendon

A patient presents with a Boutonniere deformity 4 weeks after sustaining a closed crush injury to the PIP joint. Which of the following describes the underlying pathomechanics of this deformity?

. Rupture of the terminal extensor tendon with dorsal subluxation of lateral bands
. Rupture of the central slip with volar subluxation of lateral bands
. Attenuation of the volar plate with dorsal subluxation of the central slip
. Avulsion of the FDP tendon with proximal retraction
. Contracture of the oblique retinacular ligament

Correct Answer & Explanation

. Rupture of the central slip with volar subluxation of lateral bands

Explanation

A Boutonniere deformity results from a disruption of the central slip of the extensor mechanism, allowing the lateral bands to subluxate volarly to the axis of PIP joint rotation, leading to PIP flexion and DIP extension.

Question 1693

Topic: 7. Hand and Wrist

A patient with suspected Pronator Syndrome presents with volar forearm pain and paresthesias in the thumb, index, and middle fingers. Which of the following physical examination findings most reliably differentiates Pronator Syndrome from Carpal Tunnel Syndrome?

. Positive Tinel's sign at the wrist
. Weakness of the abductor pollicis brevis
. Paresthesias exacerbated by wrist flexion
. Sensory loss over the thenar eminence
. Atrophy of the thenar musculature

Correct Answer & Explanation

. Sensory loss over the thenar eminence

Explanation

The palmar cutaneous branch of the median nerve provides sensation to the thenar eminence and branches proximal to the carpal tunnel. Sensory loss here occurs in Pronator Syndrome but is spared in Carpal Tunnel Syndrome.

Question 1694

Topic: 7. Hand and Wrist
A 45-year-old male with Kienbock's disease presents with chronic wrist pain. Imaging reveals lunate sclerosis, fragmentation, and carpal collapse, with a negative ulnar variance of 3 mm. Advanced degenerative changes are noted at the radioscaphoid joint. Which of the following is the most appropriate management?
. Radial shortening osteotomy
. Ulnar lengthening osteotomy
. Proximal row carpectomy
. Vascularized bone graft from the distal radius
. Temporary scaphotrapezio-trapezoidal (STT) pinning

Correct Answer & Explanation

. Proximal row carpectomy

Explanation

In Kienbock's disease with fixed carpal collapse and secondary arthritic changes (Lichtman Stage IV or advanced IIIB with arthritis), joint leveling procedures (radial shortening) are contraindicated. A salvage procedure like PRC or scaphoid excision/4-corner fusion is required.

Question 1695

Topic: Wrist & Carpus

A 19-year-old gymnast presents with chronic ulnar-sided wrist pain. MRI demonstrates a central, avascular tear of the triangular fibrocartilage complex (TFCC) with no evidence of distal radioulnar joint (DRUJ) instability. Ulnar variance is neutral. What is the preferred surgical treatment?

. Open repair of the TFCC to the fovea
. Arthroscopic debridement of the central tear
. Ulnar shortening osteotomy
. Darrach procedure
. Bowers hemiresection interposition arthroplasty

Correct Answer & Explanation

. Arthroscopic debridement of the central tear

Explanation

Central TFCC tears occur in the avascular zone and lack healing potential. In a stable DRUJ with neutral ulnar variance, arthroscopic debridement is the preferred treatment. Peripheral tears are vascularized and amenable to repair.

Question 1696

Topic: 7. Hand and Wrist

A clinical trial is underway for patients with wrist extensor tendinitis. One group of 100 patients are treated with short arm casting. Another group of 100 patients are treated with physical therapy. During analysis of the results, it becomes apparent that 30 patients in the physical therapy group did not complete the full course of physical therapy. Despite not completing a full course of physical therapy, these 30 patients were included in the physical therapy group for analysis. This analysis is an example of which of the following?

. Per-protocol
. Crossover analysis
. Intent-to-treat
. Bayesian analysis
. Effect size

Correct Answer & Explanation

. Intent-to-treat

Explanation

The following is an example of intent-to-treat analysis.The intent-to-treat approach aims to keep similar groups similar by not allowing for patient selection based on post-randomization outcomes (including failure to comply with the protocol). This type of analysis ensures the power of randomization so that important unknown variables that impact outcome are likely to be dispersed equally in each comparison group. Conversely, a per-protocol comparison in a clinical trial excludes patients who were not compliant with the protocol guidelines.Berger et al., in a Level 5 review, discuss many of the principles beyond randomization that are critical for preserving the comparability of the different groups. They report that masking, allocation concealment, restrictions on the randomization, adjustment for prognostic variables, and the intent-to-treat approach to data analysis are important features of designing a good clinical trial.Incorrect Answers:

Question 1697

Topic: Wrist & Carpus

A 25-year-old man sustains a Galeazzi fracture. Radiographs show a fracture of the distal third of the radial shaft with dislocation of the distal radioulnar joint (DRUJ). Which structure is the primary stabilizer of the DRUJ that is disrupted in this injury pattern?

. Extensor carpi ulnaris tendon sheath
. Triangular fibrocartilage complex (TFCC)
. Interosseous membrane
. Volar radiocarpal ligaments
. Pronator quadratus

Correct Answer & Explanation

. Triangular fibrocartilage complex (TFCC)

Explanation

The triangular fibrocartilage complex (TFCC) is the primary stabilizing structure of the DRUJ. In a Galeazzi fracture-dislocation, the DRUJ is disrupted, implying a significant tear or avulsion of the TFCC that must be addressed if the joint remains unstable after radius fixation.

Question 1698

Topic: 7. Hand and Wrist

A 30-year-old manual laborer sustains a volar oblique amputation of the index fingertip, exposing the bone of the distal phalanx. Which of the following explains why a volar advancement flap (Moberg flap) is generally contraindicated in this digit?

. The Moberg flap provides inadequate sensory re-innervation to the index finger
. Volar advancement in fingers severs the dorsal branches of the proper digital arteries, risking dorsal skin necrosis
. Fingers have a dominant dorsal venous drainage that is inevitably disrupted by the incision
. The index finger interphalangeal joints cannot tolerate the required flexion contractures for closure
. Lack of a separate volar intrinsic muscle blood supply in the index finger

Correct Answer & Explanation

. Volar advancement in fingers severs the dorsal branches of the proper digital arteries, risking dorsal skin necrosis

Explanation

The Moberg volar advancement flap is ideally suited for the thumb because the thumb has an independent dorsal blood supply via the dorsal digital arteries arising from the radial artery. In the lesser digits (fingers), the dorsal skin relies heavily on dorsal branches arising from the volar proper digital arteries. Elevating and advancing a volar flap in the fingers typically requires division of these branches, leading to a high risk of dorsal skin ischemia and necrosis.

Question 1699

Topic: 7. Hand and Wrist
During the surgical release of a severe Dupuytren's contracture in the ring finger, the surgeon encounters the spiral cord. The neurovascular bundle in this area is at high risk of iatrogenic injury. Which of the following fascial structures is spared by the disease process and lies consistently dorsal to the neurovascular bundle?
. Pretendinous band
. Spiral band
. Lateral digital sheet
. Cleland's ligament
. Grayson's ligament

Correct Answer & Explanation

. Cleland's ligament

Explanation

Cleland's ligament lies dorsal to the neurovascular bundle and is characteristically spared in Dupuytren's disease. The spiral cord is formed by the pathological involvement of the pretendinous band, spiral band, lateral digital sheet, and Grayson's ligament. The contraction of the spiral cord pulls the neurovascular bundle centrally, superficially, and proximally, placing it at high risk of injury during fasciectomy.

Question 1700

Topic: 7. Hand and Wrist

A patient with low radial nerve palsy undergoes tendon transfer utilizing the flexor carpi radialis (FCR) to power the extensor digitorum communis (EDC). The excursion of the FCR is approximately 33 mm, whereas the EDC requires approximately 50 mm for full composite extension. By what primary mechanism does the patient achieve full active digital extension post-operatively?

. Stretching of the FCR muscle belly over time through aggressive physical therapy
. Routing the transferred tendon deep to the extensor retinaculum to increase its moment arm
. The tenodesis effect utilized through active wrist flexion
. Inherent redundancy in the EDC tendon length
. Recruitment of the intrinsic hand muscles to bypass the EDC insertion

Correct Answer & Explanation

. The tenodesis effect utilized through active wrist flexion

Explanation

Tendon excursions in the forearm vary: wrist flexors/extensors have roughly 33 mm of excursion, common finger extensors 50 mm, and finger flexors 70 mm. Because the FCR (33 mm) has less excursion than the EDC (50 mm), it cannot provide full digital extension independently. Instead, patients achieve full digital extension by actively flexing the wrist (relying on intact volar flexors), which functionally increases the effective excursion of the transferred tendon through the tenodesis effect.

Test Yourself

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

On this Page