Extensor carpi radialis longus muscle

Extensor Carpi Radialis Longus Muscle

Diagram of the extensor carpi radialis longus muscle.

The extensor carpi radialis longus is one of the five main muscles that control movements at the wrist. It is located on the lateral side of the forearm and is responsible for extending and abducting the hand at the wrist joint.

Anatomy

The extensor carpi radialis longus originates from the lateral supracondylar ridge of the humerus, just above the lateral epicondyle. It runs along the forearm and inserts into the base of the second metacarpal bone on the dorsal side.

Structure

Muscles of the forearm, showing the extensor carpi radialis longus.

The muscle is fusiform in shape and is situated superficially in the forearm. It lies adjacent to the brachioradialis muscle and is partially covered by the brachialis muscle.

Innervation

The extensor carpi radialis longus is innervated by the radial nerve, specifically by its branch, the posterior interosseous nerve.

Function

The primary function of the extensor carpi radialis longus is to extend and abduct the wrist. It works in conjunction with the extensor carpi radialis brevis and other muscles of the forearm to facilitate wrist movements.

Clinical Significance

Injuries to the extensor carpi radialis longus can result in pain and weakness in wrist extension. Conditions such as lateral epicondylitis, commonly known as tennis elbow, can affect this muscle due to overuse or strain.

Related Muscles

• Extensor carpi radialis brevis
• Extensor carpi ulnaris
• Flexor carpi radialis
• Flexor carpi ulnaris

Related Pages

• Forearm
• Wrist
• Radial nerve

Cross-section of the forearm, showing the position of the extensor carpi radialis longus.

See Also

• Muscles of the forearm
• Wrist joint
• Tennis elbow