Corpus: Fibularis tertius
Synonym: peroneus tertius
1. Definition
The fibularis tertius is a muscle that belongs to the extensor muscles of the lower leg. It is a separation of the extensor digitorum longus muscle and is relatively often not present in humans.
2. Course
The fibularis tertius originates from the distal and lateral third of the fibula and the interosseous membrane. It inserts at the base of the fifth metatarsal bone.
3. Innervation
The tertius fibularis is innervated by the deep fibular nerve.
4. Function
The tertius fibularis is involved in dorsiflexion of the foot and supports pronation.