A Cadaveric Foot Model for Posterior Tibial Tendon Dysfunction

Posterior tibial tendon dysfunction (PTTD) is a significant foot disorder in which the posterior tibial tendon becomes inflamed and painful and loses its integrity. As a result, the posterior tibialis muscle/tendon unit becomes dysfunctional and, over the long term, the foot acquires a flatfoot deformity. Ideally, one would like to treat the problem early on and prevent the deformity from occurring. However, treatment to restore muscle balance in the foot in the early stages of the disorder have met with minimal success with patients eventually requiring fusions to treat the deformity and relieve pain. Currently no adequate models exist for studying the efficacy of treatment. A cadaveric foot model has been developed which simulates the muscle imbalance. The model can be used to investigate the biomechanical efficacy of surgical treatments used in early stage disease, prior to the occurrence of deformity. The model utilizes medial arch strain and talonavicular joint rotation as outcome measures.