7. Hand and Wrist MCQs

A 25-year-old motorcyclist sustains a traction injury to his right upper extremity. On examination, he has profound weakness of the intrinsic muscles of the hand and a noticeable ptosis and miosis on the right side of his face. Avulsion of which of the following nerve roots is most likely responsible for these facial findings?

A 45-year-old mechanic presents with an inability to actively extend his fingers at the metacarpophalangeal joints, though he can extend his wrist with radial deviation. Sensation over the dorsum of the hand is completely intact. Where is the most likely site of neural compression?

A patient presents with proximal median nerve compression. Radiographs reveal a bony exostosis on the anteromedial aspect of the distal humerus. Compression is likely occurring beneath a ligament connecting this exostosis to the medial epicondyle. What is this structure?

A 25-year-old male sustains a laceration over the thenar eminence. He demonstrates an inability to oppose the thumb but maintains normal thumb adduction. Which of the following muscles is primarily innervated by the deep branch of the ulnar nerve and remains functional?

A 45-year-old female presents with a distal radius fracture and concurrent severe median nerve neuropathy. During open carpal tunnel release, the surgeon must identify the precise boundaries of the tunnel. Which of the following forms the radial border of the carpal tunnel?

A 25-year-old man sustains a proximal pole scaphoid fracture. The risk of avascular necrosis is high due to the retrograde blood supply. Which of the following arteries provides the primary blood supply to the proximal pole of the scaphoid?

During a pinch mechanism, the adductor pollicis muscle is tested (Froment's sign). This muscle is innervated by the deep branch of the ulnar nerve. Where does the transverse head of the adductor pollicis originate?

A patient with De Quervain's tenosynovitis undergoes surgical release. The surgeon must be cautious of septal variations within the first dorsal extensor compartment. Which tendons reside in this compartment?

The lumbrical muscles of the hand are unique because they originate from tendons and insert onto tendons. Which of the following accurately describes the typical innervation pattern of the lumbricals?

A 45-year-old mechanic presents with weakness in extending his fingers and thumb, but normal wrist extension (with radial deviation). Sensation is entirely intact. He is diagnosed with Posterior Interosseous Nerve (PIN) syndrome. What is the most common anatomical site of PIN compression?

During a dorsal approach to the wrist for a scaphoid nonunion repair, the surgeon uses Lister's tubercle as a landmark. Which of the following tendons utilizes this bony prominence as a mechanical pulley to redirect its line of pull?

A 45-year-old mechanic presents with weakness in extending the fingers and thumb, but normal wrist extension. Sensory examination is completely normal. Compression of the involved nerve most commonly occurs at the proximal tendinous edge of which of the following muscles?

To avoid iatrogenic injury during percutaneous pinning of a fifth metacarpal neck fracture, the surgeon must be mindful of the dorsal sensory branch of the ulnar nerve. This branch typically diverges from the main ulnar nerve how far proximal to the ulnar styloid?

A 24-year-old man sustains a scaphoid waist fracture. He is at high risk for avascular necrosis of the proximal pole. What is the primary arterial supply to the proximal pole of the scaphoid?

During an open cubital tunnel release, the surgeon must be careful to protect the medial antebrachial cutaneous nerve. What is the typical anatomic relationship of this nerve to the basilic vein in the distal arm?

In a patient with ulnar tunnel syndrome (Guyon's canal syndrome), surgical release is planned. Which of the following structures forms the floor of Guyon's canal?

The anterior interosseous nerve (AIN) is a motor branch of the median nerve. Which of the following muscles is NOT innervated by the AIN?

A hand surgeon is evaluating a patient with a lumbrical plus finger following an amputation. The lumbrical muscles of the hand originate from the tendons of the flexor digitorum profundus (FDP). What is the anatomical arrangement of the lumbricals?

During an in situ ulnar nerve decompression at the cubital tunnel, the nerve is traced proximally. Which structure can compress the ulnar nerve as it pierces the medial intermuscular septum?

A patient cannot make an "OK" sign with their thumb and index finger. Which muscle is unaffected in isolated Anterior Interosseous Nerve (AIN) syndrome?