Spectrum of disease and outcome of primary amputation for diabetic foot sepsis in rural KwaZulu-Natal

Abstract

Background: Primary amputation (stump closure) for diabetic foot sepsis is perceived to have a higher re-amputation rate due to stump sepsis. A guillotine amputation with elective stump closure is widely practised due to the lower risk of stump sepsis and re-amputation.

Aims: To provide an epidemiological analysis of the spectrum of disease and outcomes of primary amputation for diabetic foot sepsis in a regional rural hospital.

Methods: A prospective cohort study of 100 patients who underwent surgery for diabetic foot sepsis over a 5-year period was undertaken at Madadeni Provincial Hospital, in northern KwaZulu-Natal. Demographic data, co-morbid profile, radiographic features, anatomical level of vascular occlusion and type of surgery performed were recorded. The Wagner classification (Wag) was used to classify disease severity. Outcome measures included length of hospital stay, in-hospital mortality and re-amputation rates.

Results: Of the 100 patients, females (n = 50) accounted for 50% of admissions. The median age was 61 years (range: 29 to 80 years). Most patients presented with advanced disease: Wag 5, n = 71 (71%); Wag 4, n = 20 (20%); Wag 3, n = 7 (7%); Wag 2, n = 2 (2%). The anatomic levels of vascular occlusion comprised: aortoiliac disease n = 2 (2%), femoropopliteal n = 21 (21%) and tibioperoneal disease n = 77 (77%). The following surgical procedures were undertaken: above knee amputation (AKA), n = 35 (35%); below knee amputation (BKA), n = 46 (46%); transmetatarsal amputation (TMA), n = 8 (8%); toe ectomy, n = 8 (8%) and debridement, n = 3 (3%). The re-amputation rate to above knee amputation was n = 2/46 (4.3%). All AKA stumps healed completely. The overall in-hospital mortality was n = 7 (7%) and median length of hospital stay was 7.8 ± 3.83 days.

Conclusion: Most patients present with advanced disease requiring a major amputation. A definitive one stage primary amputation is a safe and effective procedure for diabetic foot sepsis with distinct advantages of a short hospital stay, low reamputation rates and mortality. A guillotine amputation should be reserved for physiologically unstable patients.