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
Frequently asked questions
What does the flexor digitorum profundus do?
The flexor digitorum profundus flexes the DIP joints of the four fingers; assists MCP and wrist flexion.
What nerve innervates the flexor digitorum profundus?
Medial part: ulnar nerve (C8, T1). Lateral part: anterior interosseous branch of median nerve (C8, T1).
Where does the flexor digitorum profundus attach?
The flexor digitorum profundus originates from the proximal three-quarters of the anterior and medial ulna and interosseous membrane and inserts on the bases of the distal phalanges of the medial four fingers.
What is the blood supply of the flexor digitorum profundus?
The flexor digitorum profundus is supplied by the ulnar and anterior interosseous arteries.