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chial index, skin perfusion pressure, and magnetic resonance angiography, as well as cardiology consultation become necessary in cases of suspected or confirmed ischemia or ulcers.4-1-1-2 Neurological disordersDiabetic neuropathy, the most important among all peripheral neuropathies that affect the lower extremities is characterized by symmetrical appear-ance of the distal extremities12). Sensory neurop-athy results in decreased sensation of warmth and pain, which may delay detection of shoe-induced chafing and cold burns, with consequent serious foot lesions, which may even necessitate lower extremity amputation. Motor neuropathy causes muscle atrophy in the foot and joint contractures secondary to accumulation of advanced-glycation end products, which results in deformities such as hammertoes and crooked toes. Disruption of the arch structure leads to flat and open feet (Figure 1), with greater susceptibility to callus formation (Figure 2). Progressive autonomic neuropathy results in reduced sweating, which negatively affects the excretory function of the skin and causes dryness that predisposes patients to infection. Sympathetic neuropathy causes opening of arterio-venous shunts and consequently accelerated bone resorption and small fatigue fractures, which result in a characteristic Charcot foot deformity (Figure 3). Therefore, patients with diabetic neuropathy are at a high risk of multiple concomitant foot lesions.In addition to diabetes mellitus, trauma, osteoar-thritis, spinal disease, cranial neuropathies, prolonged Figure 1　flat and open footalcohol consumption, and aging contribute to neuropathy. Similar to diabetic neuropathy, alco-holic neuropathy tends to show a distal and symmetric presentation; however, careful history taking and details regarding the patient’s lifestyle can distinguish between these conditions13）.Evaluation of subjective symptoms, muscle atrophy, and the degree of deformity, if any, is important in addition to objective tests including the touch test, testing for vibration sense, and Achilles tendon reflex. It is also important to confirm shoe comfort and fit in patients with neuropathy because owing to sensory loss, patients are unable to determine the proper fit and tend to wear shoes that are too large or small.Figure 2　callusFigure 3　Charcot foot215