Diabetic neuropathy and foot complications

Foot ulceration and Charcot neuroarthropathy (CN) are well recognized and documented late sequelae of diabetic peripheral, somatic, and sympathetic autonomic neuropathy. The neuropathic foot, however, does not ulcerate spontaneously: it is a combination of loss of sensation due to neuropathy together with other factors such as foot deformity and external trauma that results in ulceration and indeed CN. The commonest trauma leading to foot ulcers in the neuropathic foot in Western countries is from inappropriate footwear. Much of the management of the insensate foot in diabetes has been learned from leprosy which similarly gives rise to insensitive foot ulceration. No expensive equipment is required to identify the high risk foot and recently developed tests such as the Ipswich Touch Test and the Vibratip have been shown to be useful in identifying the high risk foot. A comprehensive screening program, together with education of high risk patients, should help to reduce the all too high incidence of ulceration in diabetes. More recently another very high risk group has been identified, namely patients on dialysis, who are at extremely high risk of developing foot ulceration; this should be preventable. The most important feature in management of neuropathic foot ulceration is offloading as patients can easily walk on active foot ulcers due to the loss of pain sensation. Infection should be treated aggressively and if there is any evidence of peripheral vascular disease, arteriography and appropriate surgical management is also indicated. CN often presents with a unilateral hot, swollen foot and any patient presenting with these features known to have neuropathy should be treated as a Charcot until this is proven otherwise. Most important in the management of acute CN is offloading, often in a total contact cast.