Functional outcome in a contemporary series of major lower extremity amputations

We undertook this study to document the functional natural history of patients undergoing major amputation in an academic vascular surgery and rehabilitation medicine practice.

A retrospective review was conducted of consecutive patients undergoing major lower extremity amputation and rehabilitation in a university and Department of Veterans Affairs hospital. Main outcome variables included operative mortality, follow-up, survival, median time to incision healing, secondary operative procedures for wound management, and conversion from below-knee amputation (BKA) to above-knee amputation (AKA). For surviving patients, quality of life was determined by degree of ambulation, eg, outdoors, indoors only, or no ambulation; use of a prosthesis; and independence, eg, community housing or nursing facility.

From August 1997 through March 2002, 154 patients (130 men; median age, 62 years) underwent 172 major amputations, 78 AKA and 94 BKA, because of either critical limb ischemia (87%) or diabetic neuropathy (13%). Thirty-day operative mortality was 10%. Mean follow-up was 14 months. Healing at 100 and 200 days, as determined with the Kaplan-Meier method, was 55% and 83%, respectively, for BKA, and 76% and 85%, respectively, for AKA. Twenty-three BKA and 16 AKA required additional operative revision, and 18 BKA ultimately were converted to AKA. Survival was 78% at 1 year and 55% at 3 years. Function in surviving patients at 10 and 17 months, respectively, was as follows: 21% and 29% of patients ambulated outdoors, 28% and 25% ambulated indoors only, and 51% and 46% of patients were nonambulatory; 32% and 42% of patients used prosthetic limbs; and 17% and 8% of patients who lived in the community before amputation required care in a nursing facility.

We were surprised to find that vascular patients in a contemporary setting who require major lower extremity amputation and rehabilitation often remain independent despite infrequent prosthesis use and outdoor ambulation. Although any hope for postoperative ambulation in this population requires salvaging the knee joint, because of the morbidity incurred in both wound healing and rehabilitation efforts, aggressive effort should be reserved for selected patients at good risk. Ability to predict ambulation after BKA in the vascular population is poor.