Abstract
The foot goes through a complex series of biomechanical movements in a normal gait cycle, which result in smooth and coordinated propulsion. Various biomechanical faults may result in abnormal motion of the foot, the most important of which is abnormal pronation, causing the foot to be unstable in propulsion, leading to hypermobility of the joints, and eventual subluxation with static deformities. This abnormal motion must be treated, usually be biomechanical orthotic devices, sometimes combined with surgery. Emphasis is laid on the early recognition and correction of biomechanical faults to prevent deformities.