Outcomes and Complications of Free Anterolateral Thigh Flaps in Lower Limb Reconstruction: A Systematic Review and Comparative Analysis.

Background/Objectives: Reconstruction of complex soft-tissue defects in the lower extremity remains a significant challenge in reconstructive surgery, necessitating reliable vascularized tissue coverage when local options are exhausted. Since 1984, the free ALT flap has been recognized for its versatility, consistent vascular anatomy and low donor-site morbidity. Methods: A two-pronged approach was used, consisting of a systematic review of 18 clinical studies (published 2015-2025, n > 3400) and a retrospective analysis of 20 patients treated for high-energy traumatic defects at a single center (2017-2021). Primary endpoints included flap survival, complication rates, and functional outcomes. Results: The retrospective cohort demonstrated a 90% flap survival rate, which was not significantly different from the figure of 92.4% reported in the literature (p = 0.661). The overall complication rate was 40%, significantly higher than the 7.4% literature average (p < 0.001). Most complications were localized wound-healing disorders, such as partial necrosis, associated with the zone of injury in trauma. Despite these complications, a 100% limb salvage rate was achieved. Good functional outcomes, defined as regaining weight-bearing capacity, were observed in 80% of patients, consistent with the literature benchmarks (84.8%, p = 0.532). Conclusions: Within the limitations of this retrospective cohort and systematic review, the findings suggest that the free ALT flap is a reliable option for lower-extremity reconstruction, providing high flap survival and favorable functional outcomes despite a relatively high rate of localized wound complications in complex trauma cases.