Incidence and Risk Factors for Secondary Surgery and Amputation After Lower Extremity Limb Salvage.

Background: Traumatic defects of the lower extremity (LE) require robust soft tissue to cover critical structures and facilitate healing. Free tissue transfer (FTT) is often necessary when local tissue is inadequate. While much of the literature emphasizes free flap viability in successful limb salvage, there is limited understanding regarding the need for additional surgeries or eventual amputation. We investigated a single institution's limb salvage efforts to better understand the need for additional procedures.

Methods: All patients who underwent LE limb salvage were retrospectively reviewed from 2014 to 2022 at a single level 1 trauma center. Our primary clinical outcome was the incidence and indication of secondary surgeries following FTT.

Results: Ninety-two LE free flaps were performed during the study period. The mean age was 45 and majority were male. Seventy-two percent of flaps were fasciocutaneous while 28% were muscle flaps. Seventy-two percent of patients required a secondary surgery following FTT, with a mean of 7 total surgeries per salvage attempt. Ten percent of patients proceeded to amputation. Body mass index >30, higher frailty scores, flap type, and masquelet technique were significantly associated with subsequent amputation (P = 0.017, P = 0.024, P = 0.005, P = 0.04, respectively). Older age, the need for bony reconstruction, and longer period from injury to flap coverage were significantly associated with the need for secondary surgeries (P = 0.05, P < 0.001, and P = 0.22 respectively).

Conclusions: FTT is an important component of limb salvage. Patients undergoing limb salvage should be counseled on the need for secondary surgeries, as the process is often not complete following FTT. Furthermore, risk factors identified in this study may increase the likelihood of subsequent amputation. Thorough preoperative counseling is necessary to optimize the postoperative course and expectations in this population.