CKD, low serum hemoglobin, and low serum albumin were identified as significant risk factors for major amputation in patients with diabetic hindfoot ulcers complicated by critical infection and ischemia, and the risk of major amputation increases substantially with the number of risk factors present, from 6% with one factor to 67% with three.
Key Findings
Results
Chronic kidney disease (CKD) stage 3 or higher, hemoglobin below 10.35 g/dL, and albumin below 3.75 g/dL were independent predictors of major amputation in diabetic hindfoot ulcers with critical infection and ischemia.
Retrospective analysis of 1,663 hospitalized patients with diabetic foot ulcers; 50 with hindfoot ulcers and critical ischemia and infection were included.
88 baseline clinical and laboratory parameters were evaluated to determine key risk factors.
The three factors were independent predictors of major amputation (P < 0.05).
Results
Major amputation rate rose with the number of risk factors present.
Patients with none of the three risk factors did not undergo major amputation, even with critical infection and ischemia.
Amputation rates were 6% with one risk factor, 27% with two, and 67% with all three (P < 0.001).
Univariable logistic regression showed a strong positive correlation between the number of risk factors and major amputation rate.
Background
The risk-factor-based model refines a previous model that relied only on ischemia and infection and had limited accuracy.
The earlier preliminary model used only ischemia and infection to predict major amputation in hindfoot ulcers.
The present study aimed to identify additional risk factors and evaluate amputation rates according to them.
Conclusions
The authors state that validation in prospective studies with larger samples is needed.
The analysis was retrospective and included only 50 patients meeting the critical ischemia and infection criteria.
The abstract states prospective studies with larger sample sizes are warranted to validate the model.
What This Means
Foot ulcers on the heel or back of the foot in people with diabetes are more likely to end in a major amputation (above the foot) than ulcers elsewhere on the foot. Patients and families often want to know the real chance of limb loss given the patient's current condition, but few tools exist to answer that. This study looked back at records of 50 patients with heel-area diabetic ulcers who had both severe infection and severely reduced blood flow, out of 1,663 hospitalized patients with diabetic foot ulcers.
Three factors were linked to a higher chance of major amputation: chronic kidney disease of stage 3 or worse, low hemoglobin (below 10.35 g/dL, a sign of anemia), and low albumin (below 3.75 g/dL, a blood protein often related to nutrition and overall health). Patients with none of these did not have a major amputation, even with severe infection and poor circulation. The rate was 6% with one factor, 27% with two, and 67% with all three.
This research suggests that routine blood tests and kidney status could help give a more realistic picture of amputation risk in this high-risk group. However, the study was small and retrospective, so the numbers are rough estimates. The authors say larger, prospective studies are needed to confirm the model before it is relied upon.
Lee K, Kim W, Han S, Moon K, Namgoong S, Jeong S, et al.. (2026). Predicting Major Amputation Rates in Diabetic Hindfoot Ulcers With Critical Infection and Ischemia: A Risk-Factor-Based Model.. Journal of Korean medical science. https://doi.org/10.3346/jkms.2026.41.e247