What’s the Claim?
More than 50% of patients with diabetes who underwent transmetatarsal amputation for nontraumatic indications underwent revision amputation to a higher level. After controlling for the many confounding variables you’d expect in a large case series of this sort, only overall infirmity — as measured by a higher Charlson Comorbidity Index (CCI) — was found to be associated with an increased odds of the transmetatarsal amputation being revised to a transtibial (or higher) amputation. The optimal cut-point for using the CCI in this decision was >7.5. And even when patients with a CCI over 7.5 came to revision amputation, as would be expected in some, those revision amputations occurred much later (at a median of nearly 15 years, compared to a median of about a month for those with a CCI of ≤7.5).