CHT CHT Hand Anatomy & Biomechanics 2

Question 1

The radial nerve innervates which muscle that is commonly tested in high radial nerve palsy?

Accepted Answer

Extensor carpi radialis longus

Answer

The extensor carpi radialis longus is innervated by the radial nerve proximal to the lateral epicondyle and is used to assess the level of radial nerve palsy.

Question 2

During pinch, the first dorsal interosseous muscle is responsible for:

Accepted Answer

Index finger radial abduction

Answer

The first dorsal interosseous abducts the index finger radially, stabilizing it during lateral (key) pinch against the thumb.

Question 3

The proximal interphalangeal (PIP) joint is a hinge joint whose stability is primarily provided by:

Accepted Answer

Volar plate and collateral ligaments

Answer

PIP joint stability relies on the volar plate preventing hyperextension and the proper collateral ligaments resisting lateral stress.

Question 4

Which forearm rotation motion is primarily performed by the supinator muscle?

Accepted Answer

Supination with elbow extended

Answer

The supinator muscle is the primary supinator when the elbow is extended; biceps brachii becomes more effective at supination with the elbow flexed.

Question 5

Froment's sign is used to assess the integrity of which muscle, indicating ulnar nerve dysfunction?

Accepted Answer

Adductor pollicis

Answer

Froment's sign tests the adductor pollicis; when weakened from ulnar nerve palsy, the patient compensates with FPL flexion to maintain lateral pinch.

(CHT) Certified Hand Therapist Practice Test

(CHT) Certified Hand Therapist Practice Test

CHT CHT Hand Anatomy & Biomechanics 2