Muscle
Flexor digitorum profundus
Only muscle flexing the DIP joints
High-yield
Only muscle that flexes the DIP joints; split nerve supply — lateral half (index/middle) median (AIN), medial half (ring/little) ulnar.
Overview
The deep flexor of the fingers, the only muscle able to flex the distal interphalangeal joints. It has split (median/ulnar) innervation.
Reference facts
- Origin
Proximal three-quarters of the anterior and medial ulna and interosseous membrane
- Insertion
Bases of the distal phalanges of the medial four fingers
- Action
Flexes the DIP joints of the four fingers; assists MCP and wrist flexion
- Innervation
Medial part: ulnar nerve (C8, T1). Lateral part: anterior interosseous branch of median nerve (C8, T1)
- Blood supply
Ulnar and anterior interosseous arteries