Biomechanics of the Diabetic Foot: The Road to Foot Ulceration

Diabetic peripheral neuropathy can cause changes in foot structures and function as well as gait abnormalities, which subsequently can lead to abnormal mechanical loading of the foot. Foot deformities, such as prominent MTHs, clawed toes and Charcot neuroarthropathy, are strongly associated with and predictive of increased plantar pressure and foot ulceration. Limited joint mobility of the foot and ankle has also been suggested to increase foot pressure and to be related to foot ulceration. Additionally, changes in quantity and quality of plantar subcutaneous fat cushioning are indicators of abnormal foot loading during walking, thereby causing high plantar foot pressure. Excessive and/or repetitive pressure applied to the plantar surface of the foot appears to be the main causative factor for development of skin breakdown. However, often, it is the combination of footwear characteristics, lifestyle factors, soft tissue characteristics, plantar foot pressures and level of physical activity that contribute to the development of foot ulceration.