Extensor Digitorum

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 1
The muscles in the superficial layer of the posterior forearm.