Chapter 125 - Lower extremity amputations

Summary

Lower extremity amputations are performed for tumors, trauma, peripheral vascular disease, infection, or congenital deformity. The goal of treatment is to return the patient to a functional level allowing pain-free ambulation, which is best achieved through a multidisciplinary approach involving physician, physical therapist, and prosthetic team. Due to the psychological aspects of care, it is important to involve the patient in the decision-making process. This will help the patient to understand the intervention and (hopefully) to concur with the medical staff regarding the importance and necessity of performing the amputation, as well as postoperative expectations.

The vast majority of amputations are performed for vascular disease and infection resulting from diabetic neuropathy; the most common level is a below-knee amputation. The more proximal the amputation, the greater the metabolic cost of walking. Studies have shown that walking speed is decreased and oxygen consumption is increased with more proximal amputations.

Preoperative consideration of several important factors will directly affect the patient’s ability to successfully recover from the amputation. The goal of surgery is to leave enough viable tissue that will heal and allow for prosthetic fitting. A serum albumin level below 3.5 g/dL indicates a malnourished patient and an absolute lymphocyte count below 1,500/mm3 is a sign of immune deficiency; these values should be corrected prior to any elective amputation. Some advocate the optimization of serum glucose levels in patients with diabetes, but this treatment choice is not entirely clear. To maximize the health and nourishment of the patient, an internist and nutritionist should be included in the treatment team.