BoneShort bone

Pisiform

Latin: Os pisiforme sinistrum

Location: Hand — carpus

Paired structure: one on the left and one on the right side of the body.

View the pisiform in 3D

Function

Pea-shaped sesamoid in the flexor carpi ulnaris tendon. A sesamoid rather than a true weight-bearer: it boosts the flexor carpi ulnaris' leverage at the wrist and forms the medial wall of Guyon's canal.

Landmarks

  • Palmar prominence
  • FCU tendon embedding

Articulations (joints)

  • Triquetrum (pisotriquetral joint)

Clinical relevance

Ulnar nerve compression in Guyon's canal — between the pisiform and hamate hook — causes cyclist's palsy: clawing and ulnar-side numbness.

Educational anatomy reference, not medical advice. About this content.