The neuropathic factor in the aetiology of diabetic foot ulcers.

The nature and severity of changes due to peripheral neuropathy has been assessed clinically and electrophysiologically in 39 diabetic patients, 23 of whom had penetrating ulcers on the sole of the foot. Patients suffering from diabetic foot ulcers were found to have sensory loss to pin prick in the feet more frequently than "controls". The electrophysiological measurements confirmed the severity of the neuropathy with absent sural nerve action potentials in 95% of the ulcer patients and inexcitability of small foot muscles in 40%. Weakness of small foot muscles due to neuropathy is thought to underlie the foot deformity that leads to maldistribution of weight bearing, and subsequent pressure necrosis of analgesic skin.