Pectoralis Major Myocutaneous Flap Reconstruction for Oromandibular Defects: Analysis of Predictors for Reconstructive Outcome

Objective: The aim of the study was to identify factors predicting outcomes following pectoralis major myocutaneous flap reconstruction in complex oromandibular defects.Methods: A prospective cohort study was conducted at a tertiary care oncology center in South Asia from January 2020 to May 2022 to include consecutive cases of complex oromandibular defects reconstructed with pectoralis major myocutaneous flap. During pectoralis major myocu-taneous flap harvest surgical modifications were incorporated to preserve the choke vessel from the fourth intercostal perforator and lateral pedicle supply apart from the main pedicle from acromiothoracic artery.Results: In our series of 196 patients, overall flap compromise was noted in 17.6% with the most common pattern of failure being partial full -thickness necrosis (n = 23) and complete flap loss was identified in only 3 cases. The factors that showed statistically significant correlation with flap outcome in the univariate model were female sex (42.9% vs. 14.9%) associated with a higher incidence of flap compromise, while bipaddle pectoralis major myocutaneous flap (2.2% vs. 17.3%) and larger surface area of skin paddle (>49 cm2) (20.2%, 16%, and 0% in <49 cm(2), 50-96 cm(2), and >96 cm(2), respectively) were factors favoring a better outcome. Factors that emerged as independent prognostic variables in the multivariate model were female sex (odds ratio: 9.801, P = .001) and high body mass index (odds ratio: 1.19, P = .03) signifying a higher incidence of flap compromise.Conclusion: Pectoralis major myocutaneous flap is still the "workhorse" of head and neck reconstruction. Nevertheless, the female sex and high body mass index may serve as deterrents to the success of this flap.