The tibialis posterior is a muscle located within the deep compartment of the posterior leg, and is situated between the flexor digitorum longus and flexor hallucis longus muscles. The primary attachments of the tibialis posterior are from the posterior surface and the interosseous membrane of the tibia and fibula, with the tendon entering the foot posteriorly of the medial malleolus and attaching to the plantar surfaces of the medial tarsal bones.
When the tibialis posterior muscle contracts, it causes a number of important actions in the foot, including inversion and plantarflexion. It also contributes to the formation of the medial arch of the foot. The muscle is innervated by the tibial nerve and receives blood mainly from the posterior tibial artery.
The accompanying figure shows the muscles that make up the deep layer in the posterior leg, and includes the tibialis posterior. These muscles are essential for normal movement of the foot, and the correct functioning of the tibialis posterior is of particular importance.
The tibialis posterior muscle has four primary attachments; the posterior surface of the tibia and the interosseous membrane of the tibia and fibula. The tendon of the muscle passes through the sole of the foot and attaches to the plantar surfaces of the medial tarsal bones, posterior to the medial malleolus.
When the tibialis posterior muscle contracts, it results in a number of important movements of the foot. Firstly, the muscle causes inversion of the foot by turning the sole of the foot inwards, as well as plantarflexion, in which the angle of the foot is decreased, as if pressing the pedals of a bicycle.
The tibialis posterior also plays a crucial role in maintaining the medial arch of the foot, which is an important element of the normal functioning of the foot. This arch provides the foot with flexibility and support, and is necessary in order to provide the foot with the stability and range of motion that it needs for normal functioning.
The tibialis posterior muscle is innervated by the tibial nerve, which is the main nerve that innervates the muscles in the posterior leg. In terms of its blood supply, the main artery that provides oxygen and nutrients to the tibialis posterior is the posterior tibial artery.
Figure 1 shows the muscles that make up the deep layer in the posterior leg, including the tibialis posterior. It is this layer of muscles that are essential for normal movement of the foot, and it is therefore important to ensure that the tibialis posterior is functioning correctly.
