Muscle
Tibialis posterior
Chief invertor, supports arch
High-yield
Prime invertor and arch support; tibial nerve. Dysfunction → acquired flatfoot (pes planus).
Overview
The deepest posterior leg muscle, the main invertor of the foot and a key support of the medial longitudinal arch.
Reference facts
- Origin
- Interosseous membrane and adjacent posterior tibia and fibula
- Insertion
- Navicular tuberosity, cuneiforms, cuboid, and bases of metatarsals 2-4
- Action
- Inverts the foot and plantarflexes the ankle; supports the medial longitudinal arch
- Innervation
- Tibial nerve (L4, L5)
- Blood supply
- Posterior tibial / fibular arteries
Frequently asked questions
What does the tibialis posterior do?
The tibialis posterior inverts the foot and plantarflexes the ankle; supports the medial longitudinal arch.
What nerve innervates the tibialis posterior?
The tibialis posterior is innervated by the tibial nerve (L4, L5).
Where does the tibialis posterior attach?
The tibialis posterior originates from the interosseous membrane and adjacent posterior tibia and fibula and inserts on the navicular tuberosity, cuneiforms, cuboid, and bases of metatarsals 2-4.
What is the blood supply of the tibialis posterior?
The tibialis posterior is supplied by the posterior tibial / fibular arteries.