The Role of the Posterior Tibial Tendon in the Adult Acquired Flatfoot

Flatfoot involves a complex change in the foot architecture with a lowered medial longitudinal arch and a hindfoot eversion. It is observed in one fifth of the adult population. A distinction should be made between a flexible and a rigid form. The major cause of an acquired adult flatfoot deformity is degeneration of the tibialis posterior tendon. The tendon dysfunction results in diminished active support to the medial foot arch. There are four clinical stages of tendon dysfunction which require different therapeutic approaches. While the first stage can still be treated conservatively with immobilisation and arch support, later stages require specific surgical procedures.