The tibialis posterior is one of the muscles of the deep group within the posterior compartment of the leg.
The leg is comprised of anterior, lateral and posterior compartments. The posterior (flexor) compartment consists of two groups of muscles: a superficial group and a deep group, which are separated by a deep fascial layer.
Muscles of the superficial group within the posterior compartment of the leg
Muscles of the deep group within the posterior compartment of the leg
Origin
- Posterior surfaces of interosseous membrane and adjacent surfaces of the tibia and fibula
Insertion
- Tuberosity of navicular and adjacent region of medial cuneiform
Action
- Inversion and plantarflexion of foot
- Support of medial arch of foot during walking
Innervation
- Tibial nerve: L4,L5
Blood Supply
- Posterior tibial artery