Extensor Digitorum Brevis (EDB)

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: Intrinsic foot muscles¹

Muscles of the anterior leg²

The Mucous sheaths of the tendons around the ankle (lateral view)²

Overview

Muscle	Origin	Insertion	Innervation	Action
Extensor digitorum brevis	Calcaneus (lateral dorsal)	Bases of middle phalanx 2-4	Deep Fibular n. L5 - S1	2nd-4th Toe: MTP Extension, PIP Extension

Origin

Calcaneus (lateral dorsal surface)³

Insertion

Bases of middle phalanges of digits 2-4³

According to Brad Jones⁴, the EDB inserts distally on the lateral aspect of the EDL tendons⁴.

Nerve

Deep Fibular N. (L5, S1)³

Action

MTP/PIP 2-4: Extension³

Note

Since the EDB only inserts and acts on toes 2-4, the 5th (pinky) toe only extends through EDL contraction⁴.

MMT

“The EDL and the EDB muscles produce the motion of extension at the MTP and IP joints of the lateral four digits from a flexed position.”⁵

• Apply resistance dorsal surface of the proximal and distal phalanges into toe flexion⁵

References

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.

Gilroy AM, MacPherson BR, Wikenheiser JC, Voll MM, Wesker K, Schünke M, eds. Atlas of Anatomy. 4th ed. Thieme; 2020.

4.

Jones B. B Project Foundations. b Project; 2025.

5.

Dutton M. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 5th ed. McGraw Hill Education; 2020.