Medial displacement calcaneal tuberosity osteotomy in the treatment of posterior tibial insufficiency

Posterior tibial insufficiency first was described by Kulowski in 1936. 22 The loss of function of the posterior tibial tendon has been associated with a progressive deformity in adults that results in a painful flatfoot. During normal gait, the posterior tibial muscle creates a rigid lever for pushing off from the stance into the swing phase of gait. The posterior tibial tendon does this by inverting the foot, locking the hindfoot and the transverse tarsal joints, and allowing the function of the gastrocnemius-soleus in plantar flexing the foot. The inferior calcaneonavicular ligament, or spring ligament, originates from the coronoid cavity on the calcaneus located on the inferior surface of the calcaneus between the anterior border of the sustentaculum tali and the cuboidal articular surface. It extends to the inferior surface of the tarsonavicular bone. The medial border of this ligament is in continuity with the superior medial calcaneonavicular ligament. This ligament extends from the sustentaculum tali of the calcaneus, covers the medial segment of the talar head, and inserts on the lateral aspect of the tuberosity of the navicular bone. The integrity of the talonavicular joint is maintained by this spring ligament complex. The posterior tibial tendon at the level of the inferior aspect of the