Summary
Origins
- Proximal three-fourths of anterior and medial ulna
- Adjacent interosseous membrane
Insertions
- Bases of the distal phalanges of digits two through five
Actions
- Flexes digits two through five at the distal interphalangeal joints
- Assists with wrist flexion
The flexor digitorum profundus lies deep to the flexor digitorum superficialis. Its broad origin on the ulna and interosseous membrane sends four tendons to the fingers. Each tendon passes through the split in the superficial flexor to insert on the distal phalanx, allowing the fingertips to bend.
Its ulnar fibers blend with the flexor carpi ulnaris aponeurosis, giving the deep flexors a stable base for power grips.
It works with flexor digitorum superficialis to flex the digits and is an antagonist to the extensor digitorum.
Related Muscles
- flexor digitorum superficialis
- flexor carpi ulnaris
- flexor carpi radialis
- palmaris longus
- extensor digitorum