Extensor Carpi Radialis Longus Muscle, Posterior View

Description

Running along the posterolateral forearm, the extensor carpi radialis longus is shown arising from the lateral supracondylar ridge of the humerus and descending superficial to the radius toward the dorsum of the wrist. Its muscle belly occupies the proximal forearm and transitions distally into a long tendon that courses toward the base of the second metacarpal, lateral to extensor carpi ulnaris and typically adjacent to extensor carpi radialis brevis. Posterior bony landmarks of the humerus, radius, ulna, carpal bones, metacarpals, and phalanges provide positional reference, with the elbow joint superior and the radiocarpal joint distal. Triceps brachii is suggested proximally on the posterior arm. Posterior visualization of extensor carpi radialis longus matters because its tendon and line of pull define wrist extension and radial deviation while stabilizing the wrist during grip, a relationship that becomes obvious when you track the tendon from the lateral epicondylar region to the second metacarpal. Lateral elbow pain frequently localizes around the common extensor origin, yet distinguishing extensor carpi radialis longus from extensor carpi radialis brevis helps clarify why classic tennis elbow tends to involve the brevis more than the longus. This anatomy also guides surgical and procedural planning around the lateral elbow and proximal forearm, where the radial nerve and its branches travel in the same neighborhood. Clear landmarks. Real consequences. Use this artwork in upper limb anatomy teaching to anchor the posterior compartment of the forearm, in sports medicine or orthopaedic texts discussing lateral epicondylalgia, or in rehabilitation materials that explain resisted wrist extension and radial deviation testing. It also suits clinical hand therapy references when describing tendon excursion and wrist positioning during grip training. Anatomical accuracy verified by SciePro's Medical Advisory Board.