AnatoMemory

Muscle

Extensor carpi ulnaris

Extends and adducts the wrist

Upper limbMuscular system

High-yield

Extends and adducts (ulnar deviates) the wrist; posterior interosseous nerve.

Overview

The most medial superficial extensor, extending and ulnarly deviating the wrist. Supplied by the posterior interosseous nerve.

Reference facts

Origin
Lateral epicondyle of the humerus and posterior border of the ulna
Insertion
Base of the 5th metacarpal
Action
Extends and adducts (ulnarly deviates) the wrist
Innervation
Posterior interosseous nerve (C7, C8)
Blood supply
Ulnar / posterior interosseous arteries

Frequently asked questions

What does the extensor carpi ulnaris do?

The extensor carpi ulnaris extends and adducts (ulnarly deviates) the wrist.

What nerve innervates the extensor carpi ulnaris?

The extensor carpi ulnaris is innervated by the posterior interosseous nerve (C7, C8).

Where does the extensor carpi ulnaris attach?

The extensor carpi ulnaris originates from the lateral epicondyle of the humerus and posterior border of the ulna and inserts on the base of the 5th metacarpal.

What is the blood supply of the extensor carpi ulnaris?

The extensor carpi ulnaris is supplied by the ulnar / posterior interosseous arteries.