The fate of the ischaemic limb in diabetes: it is neuropathy that makes the difference

Evidence is presented of the deleterious effects of sensory and autonomic polyneuropathy on coexisting peripheral arterial occlusive disease (PAOD) in diabetes mellitus. Autonomic neuropathy triggers medial arterial calcification in the lower leg, which affects arterial haemodynamics, and aggravates preexisting PAOD. Calcificated arteries are incompressible and give,false blood pressure readings by sphygmomanometry, with subsequent underestimation of PAOD. Sensory neuropathy leads to loss of protective pain sensation, and precludes the timely diagnosis and treatment of limb ischaemia (no claudication, no rest pain), Absent pain perception is also critical for the outcome of surgical interventions, as wound infections and other complications will occur unnoticed. These features have consequences for the detection of high-risk patients, and for the safety, of surgery as well.