Adult Acquired Flat Foot: A New Biomechanical Classification for the Deformity Based on two Point Failure of the Medial Column

Adult acquired flatfoot deformity (AAFD) is a common condition which is historically thought to be the result of tibialis posterior tendon dysfunction. As a result, the classification of the disease and its management centres around the state of the tibialis posterior tendon. This classification system has been accepted in the absence of substantial evidence to support it. In this paper, we propose a new biomechanical classification of (AAFD) based on available evidence that not only explains the progression of the disease but also aids clinicians to formulate a management plan.