Abductor pollicis longus

The abductor pollicis longus (APL) is a muscle found in the deep layer of the posterior compartment of the forearm. As it descends, it becomes superficial and passes under the extensor retinaculum and through the 1st extensor compartment of the wrist before attaching distally. It is one of the extrinsic muscles of the hand.

Summary

Variant anatomy

  • presence of multiple slips instead of a single APL tendon 4
  •  a vertical septum spliting the 1st extensor compartment into two distinct subcompartments (i.e. APL lies in its own tunnel) 4.
Anatomy: Upper limb
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Article information

rID: 24510
Section: Anatomy
Synonyms or Alternate Spellings:
  • Abductor pollicis longus muscle
  • Abductor pollicis longus (APL)
  • APL muscle

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Cases and figures

  • Figure 1: extensor compartments of the wrist
    Drag here to reorder.
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