Lower Extremity Revascularization With Transmetatarsal Amputation Improves Healing and Reduces Major Amputation

Abstract

A transmetatarsal amputation (TMA) allows patients with forefoot wounds to maintain ambulatory function and preserves a sensate heel and ankle. However, healing after TMA is often compromised in older patients by peripheral artery disease (PAD). The aim of this study was to investigate the effect of lower extremity revascularization (LER) on TMA healing and prevention of major amputation. A retrospective review was conducted of all patients who had a TMA at three centers of a multicenter vascular practice from January 1, 2008, to December 31, 2016. In January 2012, a multidisciplinary limb salvage team consisting of vascular surgeons and podiatrists was established. Data on demographics, procedural details, and outcomes were collected. A total of 124 patients had 134 TMAs with a median follow-up of 1221 days (interquartile range [IQR], 730-1757 days). The mean age was 60.9 ± 11.5 years; 81% were men, 87% had diabetes, 56% had PAD, and 31% had coronary artery disease (CAD). Of 134 TMAs, 68% (91) healed, 10% (14) had recurrent wounds, and 22% (29) failed, requiring above- or below-knee amputation (AKA/BKA). Patients with PAD/CAD had a significantly lower healing rate (51/84 [61%] vs 40/50 [80%]; P = .021) and significantly higher AKA/BKA rate (24/84 [29%] vs 5/50 [10%]; P = .012). LER was associated with significantly improved TMA healing rates (36/52 [69%] vs 15/32 [47%]; P = .042). Open LER had a significantly higher healing rate (16/31 [52%] vs 4/20 [20%]; P = .024) and lower AKA/BKA rate (2/31 [6%] vs 9/22 [41%]; P = .002) than endovascular LER. By Kaplan-Meier analysis, the median time to healing was 295 days (IQR, 99-754 days). The median time to AKA/BKA was 1062 days (IQR, 471-1595 days). In a multivariable Cox model, LER was associated with a lower risk (hazard ratio, 0.43; P = .039) of AKA/BKA, and PAD/CAD was associated with a higher risk (hazard ratio, 5.41; P = .001); 70% (94/134) of the TMAs were performed by the multidisciplinary limb salvage team, and there was an increase in TMA for Wound, Ischemia, and foot Infection (WIfI) stage 3/4 wounds (84/94 [89%] vs 28/40 [70%]; P = .006). In a multivariable Cox model, there was no change in TMA healing or AKA/BKA rates despite the higher WIfI category. TMA is a successful and durable procedure for patients with advanced foot wounds. Whereas TMA healing is time and labor intensive, aggressive use of LER can achieve TMA healing and avoid major amputation in older patients with PAD.