Muscle/musculocutaneous versus fasciocutaneous free flap reconstruction in the lower extremity: A systematic review and meta-analysis

Background Free flaps for soft tissue coverage of the lower extremity can be broadly divided into muscle/musculocutaneous and fasciocutaneous flaps. The purpose of this systematic review and meta-analysis was to assess their different post-operative outcomes. Methods A systematic search was performed in PubMed, Scopus, and the Web of Science from their inception to February 2022. Non-randomized comparative studies, which describe any post-operative outcome of muscle/musculocutaneous and fasciocutaneous free flaps reconstruction in the lower extremity were included. Articles with duplicate titles, editorials, review articles, case series, case reports, and publications lacking an abstract, those reporting pediatric patients, those describing only muscle/musculocutaneous or fasciocutaneous free flaps, those with incomplete or incomparable post-operative outcomes, and studies involving <10 muscle/musculocutaneous or fasciocutaneous free flaps were excluded. A comparative meta-analysis was conducted on muscle/musculocutaneous and fasciocutaneous free flaps outcomes, comprising vascular thrombosis, partial or complete flap necrosis, infection, donor-site complications, non-union, and primary or recurrent osteomyelitis. The fixed-effects meta-analysis model was used when low heterogeneity (I-2 < 50%) was identified. Results Twenty-two articles with a total of 2711 flaps (1584 muscle/musculocutaneous flaps and 1127 fasciocutaneous flaps) were included in the qualitative and quantitative assessment. The rates of any flap necrosis (12.0% vs. 7.4%; p = 0.007) and donor-site complications (16.7% vs. 6.7%; p < 0.0001) were significantly higher for muscle/musculocutaneous flaps than for fasciocutaneous flaps. There were no significant differences in the rates of vascular thrombosis (10.5% vs. 10.7%; p = 0.98), complete flap necrosis (6.2% vs. 4.7%; p = 0.30), infection (19.4% vs. 14.7%; p = 0.18), non-union (18.9% vs. 14.8%; p = 0.33), and primary or recurrent osteomyelitis (14.7% vs. 12.4%; p = 0.69). Conclusion This meta-analysis revealed no significant difference in long-term post-operative outcomes, but suggested that fasciocutaneous flaps should be preferred to avoid flap necrosis and donor-site complications.