Posterior compartment of the forearm Posterior compartment of the forearm The posterior compartment of the forearm (or extensor compartment) contains twelve muscles which are chiefly responsible for extension of the wrist and digits, and supination of the forearm. It is separated from the anterior compartment by the interosseous membrane between the radius and ulna. There are generally twelve muscles in the posterior compartment of the forearm, which can be further divided into a superficial, intermediate, and deep layer. Most of the muscles in the superficial and the intermediate layers share a common origin which is the outer part of the elbow, the lateral epicondyle of
Scaphoid bone ulna to form the major bones involved in movement of the wrist. The scaphoid serves as a link between the two rows of carpal bones. With wrist movement, the scaphoid may flex from its position in the same plane as the forearm to perpendicular. Fractures of the scaphoid are the most common of the carpal bone injuries, because of its connections with the two rows of carpal bones. The scaphoid can be slow to heal because of the limited circulation to the bone. Fractures of the scaphoid must be recognized and treated quickly, as prompt treatment by immobilization or surgical