Wound healing in forefoot amputations: the predictive value of toe pressure

A retrospective study of 136 men undergoing forefoot amputation was done to test the hypothesis that preoperative toe pressure (TP) could predict the likelihood of wound healing. Demographic data included age, smoking history, diabetes mellitus (DM), hypertension, hyperlipidemia, and coronary artery disease. Clinical data included infection, preoperative arterial Doppler data, TP, wound disposition, concomitant revascularization (REV), and healing outcome. Among diabetics, no primary amputation healed with a preoperative TP < 38 mm Hg. Among REV diabetics, no healing occurred with a TP < 40 mm Hg after bypass, but no failures occurred either with a TP > 68 mm Hg or an increase in TP > or = 30 mm Hg after bypass. Nondiabetic patients exhibited no threshold TP values. Univariate analysis revealed that DM and REV were significantly different in the healed (N = 83) vs. nonhealed (N = 53) populations (p = 0.027 and 0.034). In healed patients mean TP (71.8 +/- 3.5 mm Hg SEM) was significantly higher than in nonhealed patients (45.1 +/- 4.3 mm Hg SEM, p = 0.000). Logistic regression analysis identified age > 60 years (p = 0.03), DM (p = 0.003), preoperative TP (p < 0.001), and REV (p < 0.001) as significant independent predictors of forefoot amputation healing. Healing probability was calculated and plotted vs. TP for subpopulations based on age, DM, and REV status for both primary forefoot amputation and amputation concomitant with bypass. In this study population, therefore, preoperative TP appeared to be a useful clinical tool for predicting the healing potential of both primary forefoot amputations and amputations plus concomitant bypass for any given patient.