Quick Facts
Origin: Dorsolateral aspect of calcaneus, inferior extensor retinaculum of foot, and talocalcaneal interosseous ligament.
Insertion: Extensor expansions of second to fourth toes.
Action: Extends second to fourth toes.
Innervation: Deep fibular nerve (L5-S1).
Arterial Supply: Fibular, lateral tarsal, dorsalis pedis, and arcuate arteries.
Related parts of the anatomy
Origin
The extensor digitorum brevis muscle originates from the:
- dorsolateral aspect of calcaneus;
- the inferolateral portion of the inferior extensor retinaculum of foot;
- talocalcaneal interosseous ligament.
Insertion
The fibers of the extensor digitorum brevis muscle travel anteromedially along the dorsum of the foot and insert, via three separate tendons, onto the extensor expansions of the tendons of the extensor digitorum longus muscle that go to the second to fourth toes.
Key Features & Anatomical Relations
The extensor digitorum brevis muscle is one of the muscles of the dorsum of the foot. It is a short, thin, fusiform type of skeletal muscle.
It is located:
- superior (superficial) to the cuboid and lateral cuneiform bones, and the second to fourth metatarsal bones;
- inferior (deep) to the tendons of the extensor digitorum longus and fibularis tertius muscles;
- lateral to the extensor hallucis brevis muscle.
Actions & Testing
The extensor digitorum brevis muscle is involved in multiple actions:
- extends the distal phalanges at the distal interphalangeal joints of the second to fourth toes;
- extends the middle phalanges at the proximal interphalangeal joints of the same toes;
- extends the proximal phalanges at the metatarsophalangeal joints of the same toes (Standring, 2016).
The extensor digitorum brevis muscle can be tested by extending the second to fourth toes against resistance, during which it can be seen and palpated (Sinnatamby, 2011).
References
Sinnatamby, C. S. (2011) Last's Anatomy: Regional and Applied. ClinicalKey 2012: Churchill Livingstone/Elsevier.
Standring, S. (2016) Gray's Anatomy: The Anatomical Basis of Clinical Practice. Gray's Anatomy Series 41st edn.: Elsevier Limited.
