The medial malleolus is in the centre of the medial ankle. Pain in the malleolus itself is usually die to a fracture after trauma, but stress fractures occasionally occur, especially in athletes or after ankle replacement.

Anterior to the malleolus are the medial gutter of the ankle and the talonavicular joint. Medial gutter pain often occurs in association with lateral instability or in a planovalgus foot. Talonavicular pain can be difficult to tell from ankle pain. The patient may point more downwards than into the ankle mortise, but palpation may be needed to tell the difference.

The deltoid ligament lies anterior and inferior to the malleolus, with the malleolus, the navicular tuberosity and the sustentaculum tali at the vertices of the triangle. Pain here may be due to trauma, but is often associated with adult acquired flatfoot and tibialis posterior tendonopathy. Below the deltoid, deep under the head of the talus, is the spring ligament which is also often painful in adult acquired flatfoot.

The tibialis posterior tendon runs from the posterior edge of the malleolus, over the lower part of the deltoid ligament, toward the navicular tuberosity. These bony landmarks are usually fairly obvious but if there is a lot of swelling around the tendon (paratendonitis), or the foot is oedematous or obese, you may need to palpate them to be sure which structure the pain is related to. Pain and swelling in the tendon is usually associated with a progressive flatfoot deformity (adult acquired flatfoot), typically in middle-aged women. It may also occur in younger patients, usually men, with spondyloarthropathy.

The sustentaculum tali is about 1cm below the malleolus. Pain here may indicate a tarsal coalition or subtalar arthritis. Patients with subtalar arthritis often complain of pain all round the hindfoot below the ankle, although they often say the pain is "in the ankle".