The extensor digitorum is a muscle within the superficial compartment of the posterior forearm. The tendons of the extensor digitorum pass through the 4th extensor compartment at the wrist. Attachments: Originates from the lateral epicondyle of the humerus. The tendon divides into four in the distal forearm, and inserts into the extensor hood of each digit. Actions: Extension of the digits at the interphalangeal and metacarpophalangeal joints. Innervation: Radial nerve (deep branch). Blood supply: Radial artery By TeachMeSeries Ltd (2025) Fig 1The muscles in the superficial layer of the posterior forearm. Pro Feature - 3D Model You've Discovered a Pro Feature Access our 3D Model Library Explore, cut, dissect, annotate and manipulate our 3D models to visualise anatomy in a dynamic, interactive way. Learn More Print Article Rate This Article