Tibialis Posterior
Musculus tibialis posterior
The tibialis posterior is the deepest muscle of the posterior leg and the primary invertor of the foot, also assisting plantarflexion. It is the key dynamic stabilizer of the medial longitudinal arch, and its dysfunction is a leading cause of acquired adult flatfoot. Strengthening it improves arch support and ankle stability for running and lateral movement.
- Actions
- Foot inversion, Ankle plantarflexion
- Origin
- Posterior surfaces of the interosseous membrane and the adjacent posterior surfaces of the tibia and fibula
- Insertion
- Tuberosity of the navicular and plantar surfaces of the medial cuneiform, with slips to the other cuneiforms, cuboid, and bases of the 2nd-4th metatarsals
- Innervation
- Tibial nerve (L4, L5)
- Blood supply
- Posterior tibial and fibular (peroneal) arteries
Tendons Tibialis Posterior Tendon