In order to effectively treat any part of the human musculoskeletal system, it is important to fully understand its biomechanics. Biomechanics is the study of normal mechanics (kinetics and kinematics) in the musculoskeletal system by analysing forces and their effects on anatomical structures. The normal mechanics of the foot and ankle result from the combined effects of muscle, tendon, ligament, and bone. The coordinated and unified effect of these tissues within the foot, ankle and lower extremity results in the most efficient force attenuation. To comprehend biomechanics of the foot during standing and walking, it is important to understand gait. (C) 2002 Published by Elsevier Science Ltd.