The extensor pollicis brevis is a muscle found in the deep compartment of the posterior forearm. This muscle is located in the 1st extensor compartment at the wrist and its tendon contributes to the radial border of the anatomical snuffbox.
The extensor pollicis brevis muscle originates from both the posterior surface of the radius and the interosseous membrane. It then attaches to the base of the proximal phalanx of the thumb.
This muscle is responsible for extending the metacarpophalangeal and carpometacarpal joints of the thumb.
The extensor pollicis brevis muscle is innervated by the radial nerve and its posterior interosseous branch.
The blood supply for the extensor pollicis brevis is provided by the ulnar artery.
The muscles in the deep layer of the posterior forearm can be seen in Fig 1. The extensor pollicis brevis is one of the muscles seen in the deep layer, and is located in the 1st extensor compartment at the wrist. It originates from both the posterior surface of the radius and the interosseous membrane and attaches to the base of the proximal phalanx of the thumb. Its main action is to extend the metacarpophalangeal and carpometacarpal joints of the thumb, and it is innervated by the radial nerve and its posterior interosseous branch. The ulnar artery provides the blood supply for the extensor pollicis brevis muscle.
The extensor pollicis brevis is one of the muscles located within the deep compartment of the posterior forearm, and plays a part in the movement of the thumb in the wrist. Due to its structure and attachments, it is able to extend the metacarpophalangeal and carpometacarpal joints of the thumb, and is innervated by the radial nerve and its posterior interosseous branch. The ulnar artery supplies blood to the muscle.
The extensor pollicis brevis, along with the other muscles in the deep compartment of the posterior forearm, work together to control the movement of the wrist. They provide stability to the joint and enable the thumb to move in a coordinated and precise manner. The tendon of the extensor pollicis brevis also contributes to the radial border of the anatomical snuffbox, an area located on the back of the wrist that is useful in assessing fractures and tendon injuries.
Damage or injury to any of the muscles within the deep compartment of the posterior forearm, including the extensor pollicis brevis, can limit movement of the wrist and affect the ability of the thumb to move. In some cases, hand surgery is required to repair the tendon or the nerve which supplies the muscle with motor signals. With surgery, the movement of the thumb can be restored, and the wrist can be strengthened.
The extensor pollicis brevis is an important muscle in the deep compartment of the posterior forearm as it is responsible for extending the metacarpophalangeal and carpometacarpal joints of the thumb. It is innervated by the radial nerve and its posterior interosseous branch, and is supplied by the ulnar artery. The extensor pollicis brevis muscle works in conjunction with the other muscles in the deep compartment to provide stability to the wrist joint, and its tendon plays a part in the radial border of the anatomical snuffbox. Injury or damage to the muscle can affect the movement of the wrist and thumb, but this can often be corrected by surgery.
