"Orochi" Flaps in Head and Neck Reconstruction.

Abstract

Multiple simultaneous free flap reconstructions for extensive head and neck defects in vessel-depleted necks are extremely challenging. The "Orochi" flap, described by Koshima, in which one or more secondary free flaps are anastomosed to the main pedicle of a primary free flap resulting in a fabricated chimeric flap may be a useful option when recipient vessels are scarce. Orochi free flap reconstructions for head and neck defects from 2005 to 2024 were reviewed. Postoperative outcomes for Orochi flaps were compared to outcomes for traditional free flaps and vein grafted free flaps using multivariable regression and propensity score matching. Seventy-two Orochi flaps were compared to 385 traditional flaps, and 47 vein grafted flaps. The flap loss rate was 0% for primary Orochi flaps and 4% for secondary Orochi flaps. Only vein grafted flaps (OR= 68.7 (95% CI: 2.6-1788.6)) and history of prior free flaps (OR = 44.2 (95% CI:2.2-879.4)) were found to be independent predictors of total flap loss on multiple regression analysis. In propensity score matched analysis, Orochi flaps had shorter median hospital stays (8 vs. 10 days, p <0.05), and vein-grafted flaps had higher rates of overall complications (21% vs. 8.3%, p = 0.037) and total flap loss (7.1% vs. 0%, p = 0.035) compared to traditional flaps. Orochi flaps are a reliable option for head and neck reconstruction requiring multiple simultaneous free flaps in patients with vessel-depleted necks, possibly offering an advantage over vein grafting to reach recipient vessels at distant sites.