Adductor Pollicis Muscle Anatomy

Origin:

  • Transverse Head: Originates from the anterior surface of the third metacarpal bone.
  • Oblique Head: Arises from the bases of the second and third metacarpals, the capitate bone, and adjacent carpal bones.
  • Insertion: Both heads converge to insert onto the medial side of the base of the proximal phalanx of the thumb, the ulnar sesamoid, MP joint capsule, the thumb's extensor tendon and volar plate of the thumb MP joint.
  • Innervation: Deep branch of the ulnar nerve (C8 and T1)
  • The adductor pollicis is the largest of the thenar muscles.
Diagrams & Photos
  • First dorsal interosseous muscle has been cut off the first metacarpal to expose the adductor aponeurosis and adductor muscle. Extensor pollicis longus (EPL) noted.
    First dorsal interosseous muscle has been cut off the first metacarpal to expose the adductor aponeurosis and adductor muscle. Extensor pollicis longus (EPL) noted.
Key Points
  • The deep branch motor branch of the ulnar nerve and the deep vascular palmar arch pass through the interval between the transverse and oblique heads of the adductor pollicis at the level of the long metacarpal.
  • The adductor pollicis is a dynamic stabilizer of the the ulnar side of the thumb MP joint.
Anatomy References
Anatomic Abbreviations
Hand Surgery Resource Anatomy Diagnostic Guide (Chapter)