++
A 60-year-old woman with uncontrolled type 2 diabetes, hypercholesterolemia, and tobacco use presented with a 2-month history of a nonhealing ulceration on her left foot (Figure 219-1). She believes this started as a callus that peeled off. She presented with the ulcer, loss of protective sensation, and a nonpalpable posterior tibial pulse. She began treatment in a wound care center without any success. Noninvasive arterial studies showed severe vascular disease and thus, she underwent revascularization. While in the hospital, she quit smoking and gained control of her diabetes. Her ulcer healed, and she continues to take her diabetes medications and no longer smokes.
++
++
Ulcerations occur from ongoing biomechanical forces or trauma in the insensate foot. Ulcers require adequate blood flow to heal. Nonhealing ulcers are often a result of peripheral ischemia seen in patients with diabetes and other vascular diseases. Treatment includes local wound care and improvement or correction of underlying factors causing ischemia. Untreated ischemic ulcers become infected and may require amputation.
++
++
Of patients with diabetes, 15% to 25% will develop an ulcer at an annual incidence of 1% to 4%.1
+++
ETIOLOGY AND PATHOPHYSIOLOGY
++
Microvascular dysfunction is an important component of the disease process that occurs in diabetic foot disease. The abnormalities observed in the endothelium in patients with diabetes are not well understood, and evidence suggests that endothelial dysfunction could be involved in the pathogenesis of diabetic macroangiopathy and microangiopathy.2 Microangiopathy is a functional disease, in which neuropathy and autoregulation of capillaries lead to poor perfusion of the tissues, especially at the wound base. Also, an occlusion of the small vessels may occur.
++
Diabetes for more than 10 years, especially with poor glycemic control and the presence of other macro- or microvascular complications such as nephropathy and retinopathy.
Peripheral vascular disease from any cause or other vascular risk factors, including dyslipidemia and tobacco use.
Neuropathy caused by diabetes is a sign of microvascular disease, and an accompanying loss of protective sensation may delay detection.
History of a previous ischemic ulcer.
++
Pain.
Gray/black fibrotic base (Figures 219-1 and 219-2).
Undermined skin margins.
Punched-out appearance.
Nonpalpable pulses.
Associated trophic skin changes (e.g., absent pedal hair and thin shiny skin).
++