Acute limb ischemia is caused by embolism or thrombosis, or rarely by dissection or trauma. Thrombosis is usually caused by peripheral vascular disease (an atherosclerotic disease that leads to blood vessel blockage), while an embolism is usually of cardiac origin. In the United States, ALI is estimated to occur in 14 out of every 100,000 people per year. With proper surgical care, acute limb ischemia is a highly treatable condition; however, delayed treatment (beyond 6 to 12 hours) can result in permanent disability, amputation, and/or death.