Flexor digitorum profundus

Dr Henry Knipe et al.

Flexor digitorum profundus (FDP) makes up the third layer of the anterior compartment of the forearm along with flexor pollicis longus. It passes through the carpal tunnel.


  • origin: proximal, anterior surface of ulna and adjacent interosseous membrane
  • insertion: volar surface of distal phalanges 2-5
  • innervation
  • action: flexion at the distal interphalangeal, proximal interphalangeal and wrist joints
Upper limb anatomy
Share article

Article information

rID: 23265
Section: Anatomy
Synonyms or Alternate Spellings:
  • Flexor digitorum profundus
  • FDP

Support Radiopaedia and see fewer ads

Cases and figures

  • Drag
    Figure 1: carpal tunnel diagram
    Drag here to reorder.
  • Updating… Please wait.

    Alert accept

    Error Unable to process the form. Check for errors and try again.

    Alert accept Thank you for updating your details.