Abductor Pollicis Longus (APL) Anatomy

Origin: Middle third of the posterior surfaces of the ulna and radius, and the interosseous membrane.

Insertion: Base of the first metacarpal bone of the thumb.

Innervation: Posterior interosseous nerve.

Nerve: Radial nerve (via its deep branch)

Diagrams & Photos
  • APL
Key Points
  • Abductor Pollicis Longus (APL) typical has 2 to 7 slips. The multiple slips are frequently seen when opening the first dorsal extensor compartment during surgical release of the compartment for DeQuervain's tenosynovitis.  
Anatomy References
Anatomic Abbreviations
Hand Surgery Resource Anatomy Diagnostic Guide (Chapter)