Extensor carpi ulnaris

A muscle located in the forearm that primarily facilitates wrist extension and ulnar deviation.

Extensor carpi ulnaris is a muscle of the posterior compartment of the forearm. This muscle originates from the lateral epicondyle of the humerus and the posterior border of the ulna. It inserts into the base of the fifth metacarpal bone, playing a significant role in wrist movement.

Terminologia Anatomica

extensor-carpi-ulnaris

System

Muscular system

Function

The primary role of the extensor carpi ulnaris is to extend and adduct the wrist joint, contributing to a variety of hand movements. This muscle is essential for stabilizing the wrist during activities such as gripping, throwing, and racquet sports. By extending the wrist, it allows for a better reach while maintaining stability, which enhances the effectiveness and precision of hand functions. Furthermore, the extensor carpi ulnaris works in conjunction with other muscles in the forearm to coordinate fine motor skills, making it indispensable for everyday tasks that require dexterity.

Location

Situated on the dorsal side of the forearm, the extensor carpi ulnaris is positioned medially to other extensor muscles. It spans from the lateral epicondyle of the humerus, running down the posterior aspect of the ulna, to its insertion on the base of the fifth metacarpal bone. This location allows it to effectively influence the wrist joint, being strategically placed to provide the necessary mechanical advantage for its functions. Its proximity to the wrist allows it to play a pivotal role in both gross and fine motor movements of the hand, integrating smoothly with the surrounding musculature.

Did You Know?

The extensor carpi ulnaris is one of the key muscles involved in stabilizing the wrist during activities that require precision.
Injuries to the extensor carpi ulnaris can lead to difficulties in wrist movement and grip strength.
This muscle works in a synergistic manner with the flexor carpi ulnaris to balance wrist movements.