[Degeneration of the posterior tibial tendon : Established and new concepts].

backgroundThe most common cause of degeneration of the posterior tibial tendon is a congenital valgus deformity of the calcaneus. Other associated pathologies are forefoot supination, forefoot abduction and shortening of the gastrocnemius muscle. DIAGNOSTICS: Loaded x‑rays of the foot in three planes as well as the hindfoot alignment view enable evaluation of the axis of the foot under static loading conditions. The posterior tibial tendon can be imaged with ultrasound and magnetic resonance imaging (MRI). The fatty degeneration of the posterior tibial muscle can be identified in MRI. CONSERVATIVE THERAPY: Unloading of the posterior tibial tendon can be achieved by orthotics with medial support or braces. SURGICAL THERAPY: The surgical therapy of the posterior tibial tendon alone has not been proven to be successful. The key element is the correction of the hindfoot valgus by medializing calcaneal osteotomy. Depending on the deformity, an additional lateral lengthening osteotomy of the calcaneus, as well as a dorsal open wedge osteotomy of the medial cuneiform bone (Cotton osteotomy) can additionally be indicated. The transposition of the tendon of the flexor digitorum longus muscle to the navicular bone is used to augment the posterior tibial tendon. Ruptures of the plantar calcaneonavicular ligament are sutured, in addition a sinus tarsi spacer can be implanted to protect medial soft tissues. A shortening of the gastrocnemius muscle is addressed by release of the aponeurosis. First results are published on use of biologically active substances, such as platelet rich plasma.

resultsThe correction of the hindfoot deformity as well as the subsequent treatment of the different components of the pathology lead to a significant improvement in foot function. Pre-existing degenerative alterations are limiting factors.