7. Hand and Wrist MCQs

A surgeon is performing an anterior (Henry) approach to the proximal radius. To safely expose the proximal third of the radius, the supinator muscle must be elevated. The posterior interosseous nerve (PIN) runs through the supinator. The proximal fibrous edge of the superficial head of the supinator is anatomically known as:

A hand surgeon is treating a severe flexor tendon laceration in zone II. During the repair, it is essential to reconstruct the tendon sheath to prevent bowstringing. Which two annular pulleys are the most mechanically critical and must be preserved or reconstructed?

The deep palmar arch of the hand is a crucial collateral circulatory pathway. It is formed primarily by the terminal part of the radial artery. Which structure most commonly anastomoses with it to complete the arch?

In the deep compartments of the hand, the deep palmar space is anatomically divided into the thenar space and the midpalmar space. Which structure physically separates these two deep fascial spaces?

A patient is evaluated for weakness in making an 'OK' sign, demonstrating an inability to flex the interphalangeal joint of the thumb and the distal interphalangeal joint of the index finger. The injured nerve is ultimately derived from which cord(s) of the brachial plexus?

During a wide surgical release for an aggressive tendon sheath infection in the hand, multiple flexor pulleys are encountered. Which combination of pulleys is considered biomechanically most critical to prevent bowstringing of the flexor tendons and must be preserved?

The Triangular Fibrocartilage Complex (TFCC) is the primary stabilizer of the distal radioulnar joint (DRUJ). Which specific component of the TFCC is the primary restraint to dorsal and volar translation of the radius relative to the ulna?

Following a scaphoid waist fracture, the proximal pole is at high risk for avascular necrosis due to its retrograde blood supply. Which vessel provides the primary intraosseous retrograde blood supply to the proximal scaphoid?

In Guyon's canal at the wrist, the ulnar nerve bifurcates into superficial and deep branches. Which of the following anatomic structures forms the primary floor of Guyon's canal?

The central band of the forearm interosseous membrane is critical for longitudinal stability of the radioulnar relationship. What is the predominant fiber orientation of this central band?

A 55-year-old cyclist complains of numbness and tingling in his ring and small fingers, diagnosed as ulnar tunnel syndrome (Guyon's canal compression). When releasing Guyon's canal, the surgeon must understand its anatomic boundaries. What structure forms the floor of Guyon's canal?

A 24-year-old presents with a scaphoid waist fracture. The surgeon opts for percutaneous screw fixation. A deep understanding of the scaphoid's blood supply is necessary to appreciate the risk of avascular necrosis. Which vessel provides the primary blood supply to the proximal pole of the scaphoid?

A 60-year-old female is undergoing an open carpal tunnel release. The surgeon is extending the incision proximally into the distal forearm. To avoid injury to the palmar cutaneous branch of the median nerve, where should the incision be placed relative to the palmaris longus tendon?

During closed reduction and percutaneous pinning of a supracondylar humerus fracture in a pediatric patient, a medial pin is placed. The patient subsequently exhibits weakness in spreading their fingers and numbness in the small digit. At what anatomical location does the affected nerve run in relation to the medial epicondyle?

A patient experiences an inability to extend the fingers at the metacarpophalangeal joints, but wrist extension is preserved with radial deviation. Entrapment of the responsible nerve most commonly occurs at the Arcade of Frohse. Which structure forms this arch?

Scaphoid fractures are prone to nonunion and avascular necrosis due to their unique blood supply. How does the predominant vascular supply enter the scaphoid?

Extensor pollicis longus (EPL) tendon ruptures can occur following distal radius fractures. The EPL tendon typically passes around a bony prominence on the dorsal radius. This prominence acts as a pulley and separates which two extensor compartments?

During an ulnar collateral ligament (UCL) reconstruction using the docking technique, the surgeon decides to transpose the ulnar nerve subcutaneously. Which of the following is the primary risk factor for postoperative ulnar neuropathy in this specific scenario?

A 42-year-old competitive weightlifter undergoes an anterior single-incision repair for an acute complete distal biceps tendon rupture.

Postoperatively, he complains of significant numbness over the lateral aspect of his forearm. Which nerve is most likely injured?