The surgical loss of the foot or leg is vigorously resisted by podiatrists who are committed to the conservation of limbs at risk because of peripheral vascular disease. Pathologic changes in blood vessels may, however, progress to a point where no other option is available to the patient. This study assesses amputation of the extremities and investigates tissue alterations that can be identified in diseased blood vessels implicated in these circumstances. Gross pathology and scanning electron microscopy are examined in this, the first of a two-part study.