Abductor pollicis longus muscle

This tutorial focuses on the abductor pollicis longus, a deep extensor muscle of the forearm. It covers the muscle's origin at the dorsal surfaces of the radius and ulna, its insertion at the base of the first metacarpal bone, and its additional attachment to the trapezium. The muscle is innervated by the radial nerve, specifically the posterior interosseous nerve. The abductor pollicis longus is responsible for thumb abduction and radial deviation at the wrist joint. The video concludes with a call to explore more anatomy resources on Kenhub.

Which muscle group does the abductor pollicis longus belong to?

• Flexors of the forearm

• Deep extensors of the forearm

• Superficial muscles of the hand

• Intrinsic muscles of the hand

Where does the abductor pollicis longus muscle originate?

• Medial epicondyle of the humerus

• Lateral epicondyle of the humerus

• Dorsal surfaces of the radius and ulna

• Ventral surfaces of the radius and ulna

What nerve is responsible for the innervation of the abductor pollicis longus?

• Ulnar nerve

• Radial nerve

• Median nerve

• Musculocutaneous nerve

What is the primary function of the abductor pollicis longus?

• Adduction of the thumb

• Extension of the thumb

• Flexion of the thumb

• Abduction of the thumb

What additional movement does the abductor pollicis longus assist with at the wrist joint?

• Supination

• Pronation

• Radial deviation

• Ulnar deviation