Medial malleolus

The medial surface of the lower extremity of tibia is prolonged downward to form a strong pyramidal process, flattened from without inward - the medial malleolus.


 * The medial surface of this process is convex and subcutaneous;


 * its lateral or articular surface is smooth and slightly concave, and articulates with the talus;


 * its anterior border is rough, for the attachment of the anterior fibers of the deltoid ligament of the ankle-joint;


 * its posterior border presents a broad groove, the malleolar sulcus, directed obliquely downward and medialward, and occasionally double; this sulcus lodges the tendons of the Tibialis posterior and Flexor digitorum longus.

The summit of the medial malleolus is marked by a rough depression behind, for the attachment of the deltoid ligament.