Medial retromalleolar region

The medial retromalleolar region of ankle corresponds to the space located behind the medial malleolus of the tibia. It is situated in the posteromedial portion of the posterior ankle region.

This region is characterized by the presence of the flexor retinaculum, a thickening of deep fascia that extends from the medial malleolus to the heel bone. It forms the covering for a fibro-osseous space known as the tarsal tunnel. Within this tunnel, the long tendons of the deep posterior leg muscles pass to reach the sole of the foot. These include the tendons of the tibialis posterior, flexor hallucis longus, and flexor digitorum longus muscles. Furthermore, the posterior tibial vessels and the tibial nerve also traverse the tarsal tunnel in the medial retromalleolar region of ankle.

All the deep posterior leg muscles contribute to plantar flexion at the ankle joint. Given its medial position, the tibialis posterior muscle also contributes to the inversion of the foot.