Risk of reamputation in diabetic patients stratified by limb and level of amputation: a 10-year observation

Abstract

Objective: This study examined the risk of reamputation, stratified by original level of amputation, in a population of diabetic patients. We also illustrated reamputation rates by ipsilateral and contralateral limbs.

Research design and methods: The study population included 277 diabetic patients with a first lower-extremity amputation performed between 1993 and 1997 at University Hospital in San Antonio, Texas. Reamputation episodes for the ipsilateral and contralateral limbs were recorded through 2003. Using a cumulative incidence curve analysis, we compared the reamputation rate by limb. Cumulative rates of reamputation were calculated for each limb at each amputation level at 1, 3, and 5 years.

Results: Cumulative rates of reamputation per person were 26.7% at 1 year, 48.3% at 3 years, and 60.7% at 5 years. Ipsilateral reamputation per amputation level at the 1-, 3-, and 5-year points were toe: 22.8, 39.6, and 52.3%; ray: 28.7, 41.2, and 50%; midfoot: 18.8, 33.3, and 42.9%; and major: 4.7, 11.8, and 13.3%. For contralateral reamputation, the rates at 1, 3, and 5 years were toe: 3.5, 18.8, and 29.5%; ray: 9.3, 21.6, and 29.2%; midfoot: 9.4, 18.5, and 33.3%; and major: 11.6, 44.1, and 53.3%.

Conclusions: This study showed that a patient is at greatest risk for further same-limb amputation in the 6 months after the initial amputation. Although risk to the contralateral limb rises steadily, it never meets the level of that of the ipsilateral limb. This finding will help clinicians focus preventive efforts and medical resources during individualized at-risk periods for diabetic patients undergoing first-time amputations.