Posterior compartment of the forearm
The forearm is divided into the posterior compartment and the anterior compartment by the deep fascia, lateral intermuscular septum and the interosseous membrane between the ulna and radius.
Muscles
The posterior compartment of the forearm contains 11 muscles, divided into deep and superficial layers.
Superficial
- mobile wad of Henry
- extensor digitorum (ED) muscle
- extensor digiti minimi (EDM) muscle
- extensor carpi ulnaris (ECU) muscle
Deep
- supinator muscle
- extensor pollicis longus (EPL) muscle
- extensor pollicis brevis (EPB) muscle
- abductor pollicis longus (APL) muscle
- extensor indicis (EI) muscle
The anconeus muscle is sometimes considered part of the posterior compartment of the forearm rather than part of the posterior compartment of the arm.
Arterial supply
Anterior and posterior interosseous arteries, which are branches of the short common interosseous artery, arise from the proximal ulnar artery.
Innervation
All muscles in the extensor compartment are supplied by the radial nerve.
