Nonoperative treatment of posterior tibial tendon dysfunction

One of the most common causes of acquired flatfoot deformity in adults is d ysfunction of the posterior tibial tendon. The main function of the posteri or tibial tendon is to invert the midfoot and lock the transverse tarsal jo ints (talonavicular and calcaneocuboid joints). When the tendon fails to fu nction properly, a progressive flatfoot deformity develops. Because the dis ease process is a continuum, a staging system has been devised to offer gui delines for nonoperative and operative treatment of this problem. The ratio nale for nonoperative treatment of this disorder is to support the longitud inal arch and to decrease the valgus angulation of the calcaneus for flexib le flatfoot deformity, and to immobilize and support the hindfoot and midfo ot for rigid flatfoot deformities. The success of nonoperative treatment fi rst requires the assessment of the flexibility of the flatfoot deformity. F or a flexible deformity, the custom orthosis should be fitted with the foot and ankle in a corrected position as close to the neutral position as poss ible. Whereas, for a rigid deformity, it is imperative for the custom ortho sis to be fitted with the affected foot and ankle in an in situ position.