Extensor Pollicis Longus (EPL)

Authors
Affiliations

Nate Yomogida, B.S., SPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, B.S., SPT

Doctor of Physical Therapy

B.A. in Neuroscience

Figure 1: Muscles that move the Forearm1

Mucous sheaths of the dorsal hand2

Mucous sheaths of the dorsal hand2

Transverse section of distal forearm2

Transverse section of distal forearm2

Transverse cut of the Hand2

Transverse cut of the Hand2
Reading list
  • MMT3
Muscle Origin Insertion Innervation Action
Extensor pollicis longus Dorsal ulna
IO membrane		 Base of 1st Distal phalanx Radial n.
C7 - C8		 Wrist: Extension, Radial dev.
CMC: Abduction
1st MCP & IP: Extension

Origin

  • Ulna (Posterior surface)4
  • IO membrane4

Insertion

Base of distal phalanx of thumb4

Innervation

Posterior Interosseous N. (C7, C8)4

Action

  • Wrist: Extension4
  • 2nd MCP, PIP, DIP: Extension4

Notes

1.
Betts JG, Blaker W. Anatomy and Physiology. 2nd ed. OpenStax; 2022. https://openstax.org/details/books/anatomy-and-physiology-2e/?Book%20details
2.
Gray H. Anatomy of the Human Body. 20th ed. (Lewis WH, ed.). Lea & Febiger; 1918. https://www.bartleby.com/107/
3.
Weinstock D. NeuroKinetic Therapy: An Innovative Approach to Manual Muscle Testing. North Atlantic Books; 2010.
4.
Gilroy AM, MacPherson BR, Wikenheiser JC, Voll MM, Wesker K, Schünke M, eds. Atlas of Anatomy. 4th ed. Thieme; 2020.

Citation

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