59 – Disorders of the midtarsal joints

TLDR: The talonavicular and calcaneocuboid joints and the tarsometatarsal joints comprise the midtarsal joints and functionally, they act as one structure.

Abstract: The talonavicular and calcaneocuboid joints and the tarsometatarsal joints comprise the midtarsal joints. Functionally, they act as one structure. Movement is possible in six directions: dorsiflexion–plantiflexion, adduction–abduction and pronation– supination. It is important for the ankle and subtalar joints to be stabilized when these movements are performed; this is achieved by dorsiflexion in the ankle joint and strong valgus pressure at the heel. Due to the obliquity of the joint surfaces and the greater mobility of the talonavicular joint, dorsiflexion is usually accompanied by some abduction, whereas plantiflexion induces adduction. At the distal (Lisfranc’s) joint, considerable rotation round the second metatarsal shaft is possible (Fig. 59.1). Because of the specific structure of the joint line, plantiflexion of the metatarsals will always be accompanied by a movement towards the second metatarsal. Therefore a plantiflexion movement at the midtarsal joint increases the curvature of the anterior arch, whereas dorsiflexion is associated with flattening.