7. Hand and Wrist MCQs

During surgical release of Guyon's canal, a surgeon identifies the anatomical borders. The floor of Guyon's canal is primarily formed by which structure?

The recurrent motor branch of the median nerve (the "million dollar nerve") classically branches from the median nerve at which location relative to the transverse carpal ligament?

A patient presents with isolated weakness of the abductor digiti minimi, interossei, and the two ulnar lumbricals, but has normal sensation over the entire little finger and the ulnar half of the ring finger. Based on the zones of Guyon's canal, a compressive lesion is most likely located in which zone, and bounded radially by which structure?

A patient presents with an inability to actively extend the proximal interphalangeal (PIP) and distal interphalangeal (DIP) joints of the index and middle fingers. Active flexion of the metacarpophalangeal (MCP) joints is also weakened. Which of the following accurately describes the origin and innervation of the primarily affected intrinsic muscles?

An adult patient presents with a severe posterior interosseous nerve (PIN) syndrome. On examination, the patient demonstrates weakness in thumb and finger extension. When asked to extend the wrist, the hand deviates radially. This radial deviation occurs because the PIN lesion spares the innervation to the:

During flexor tendon repair in Zone II of the hand, preserving the critical pulley system is essential to prevent bowstringing of the tendon. Which two pulleys are considered the most biomechanically critical for normal finger flexion?

An avid cyclist presents with isolated weakness of the intrinsic hand muscles, resulting in a weak pinch grip, but maintains normal sensation over the volar and dorsal little finger. Compression of the ulnar nerve is most likely occurring in which anatomical region?

A 45-year-old mechanic presents with an inability to actively extend his fingers at the metacarpophalangeal joints, but his wrist extension is preserved with slight radial deviation. Examination reveals no sensory deficits. The most likely site of nerve compression is between the two heads of which muscle?

A 22-year-old gymnast presents with chronic ulnar-sided wrist pain. MRI shows a tear of the triangular fibrocartilage complex (TFCC). Healing potential is highly dependent on the vascularity of the TFCC. Which portion of the TFCC receives the most robust blood supply?

A 24-year-old man sustains a scaphoid waist fracture after a fall on an outstretched hand. He is at high risk for avascular necrosis of the proximal pole due to its specific retrograde vascularity. What is the primary arterial supply to the proximal pole of the scaphoid?

Following a distal radius fracture, a patient develops spontaneous rupture of the extensor pollicis longus (EPL) tendon. The EPL tendon normally utilizes which bony landmark as a pulley before inserting on the distal phalanx of the thumb?

A trauma patient sustains a severe deep laceration over the volar-ulnar aspect of the wrist, transecting the ulnar artery. Anatomically, the superficial palmar arch receives its major contribution from the ulnar artery and is completed radially by which of the following structures?

A patient with severe, long-standing carpal tunnel syndrome presents with noticeable atrophy of the thenar eminence. Which intrinsic muscles of the hand, aside from the thenar group, are predominantly innervated by the affected nerve?

A 35-year-old carpenter suffers a deep laceration to the volar palm, severing the flexor digitorum profundus (FDP) tendon to the index finger. Which lumbrical muscle originates from this specific tendon, and what is its normal innervation?

A patient presents with an isolated laceration to the recurrent motor branch of the median nerve at the wrist. Which of the following intrinsic thumb muscles will most likely retain normal function due to its sole innervation by the ulnar nerve?

A 30-year-old carpenter suffers a deep laceration to the volar aspect of his hand, severing the deep branch of the ulnar nerve. Which of the following lumbrical muscles will most likely lose innervation?

A patient presents with weakness of finger and thumb extension but normal wrist extension (with radial deviation) and no sensory deficits. The affected nerve is most likely compressed by a fibrous arch located at the proximal edge of which muscle?

The triangular fibrocartilage complex (TFCC) is crucial for distal radioulnar joint (DRUJ) stability. The primary bony attachment of the deep radioulnar ligaments (ligamentum subcruentum) is located at which structure?

The intrinsic blood supply to the flexor tendons within the digital sheath is critical for healing after repair. The vinculum breve profundus (VBP) provides vascularity to the flexor digitorum profundus tendon at which location?

The clinical and radiographic images below belong to a patient with Chondroectodermal Dysplasia. Based on the typical presentation of this syndrome, which specific hand anomaly was most likely resected prior to these photographs being taken?