Comparative Effectiveness of Transmetatarsal First Ray Amputation and Hallux Amputation in a Diabetic Foot Ulcer Cohort

Abstract

Background:

The optimal amputation level along the first ray in diabetic foot disorders remains disputed, particularly the choice between transmetatarsal first ray amputation and hallux amputation. This study aimed to compare mid- to long-term outcomes between these surgical approaches, focusing on ulcer recurrence and revision rates.

Methods:

A retrospective analysis was conducted at a tertiary care center, examining 112 patients who underwent first ray amputations between 2000 and 2023. The study compared outcomes over 5 years between transmetatarsal first ray amputation (n = 28) and hallux amputation (n = 84), which was defined as any amputation at the hallux. The primary outcome was ulcer recurrence; secondary outcomes were need for revision surgery and revision-free survival. Multivariable Cox regression analysis was performed, adjusting for age, sex, chronic kidney disease, peripheral arterial disease, coronary heart disease, and history of contralateral amputation. Additionally, a propensity score matched analysis was conducted to control for significant baseline age differences.

Results:

After a maximum follow-up of 48 months, no statistically significant difference was found in ulcer recurrence between the 2 procedures in the unmatched cohort (HR = 0.56, P = .078, 95% CI: 0.30-1.07). Similarly, no significant difference was observed in revision surgery rates (HR = 0.680, P = .189, 95% CI: 0.35-1.31). In the propensity-matched analysis, transmetatarsal amputation was associated with a significantly lower risk of ulcer recurrence (HR = 0.33, 95% CI: 0.14-0.78; P = .011). Age emerged as a significant predictor of ulcer recurrence, with each additional year associated with reduced risk (HR = 0.977, P = .001, 95% CI: 0.96-0.99). Higher stage of PAD (stage III or higher) showed lower risk of ulcer recurrence compared with lower stage (HR = 0.34, P = .01, 95% CI: 0.15-0.78). Chronic kidney disease was associated with an increase of revision (HR = 2.067, P = .018, 95% CI: 1.13-3.77 ), a history of minor amputation or conservative surgery on the contralateral side significantly increased revision risk (HR = 5.798, P = .021, 95% CI: 1.30-26.03).

Conclusion:

The study found no clear advantage of either transmetatarsal or hallux amputation regarding risk of revision surgery, whereas the risk of ulcer recurrence was significantly lower in the propensity-matched transmetatarsal amputation group.