Diabetic Foot Biomechanics and Ulceration

الملخص

Diabetes mellitus affects the structure and function of the foot leading to sensorimotor neuropathy, foot deformities,
callus formation and also limits joint mobility. High plantar pressure and autonomic dysfunction interact and
contribute to the development of foot ulceration. Trauma is also needed in addition to neuropathy and vascular
disease to cause tissue breakdown. This trauma may be intrinsic, repetitive stress from high pressure or callus.
The body responds to repetitive high pressures or microtrauma with callus formation. If callus formation becomes
excessive it will contribute to high pressure. Ankle dorsiflexion and subtalar range of motion are reduced in
diabetes, so also the motion at first metatarsophalangeal joints. These along with changes in tendon, muscles, and
bone with thickening and hardening of skin and fascia also add to stiffness and limited joint mobility. These changes
are secondary to enzymatic glycosylation. Offloading of the diabetic wound is a key factor in successful wound
healing. Total contact cast is generally reviewed as a reference standard for offloading the diabetic wound however
several useful alternatives also exist.