Incidentally detected anomalous pectoralis major muscle during reconstruction of oral cavity cancer

Abstract

The congenital deficiency of pectoralis major muscle is quite uncommon. Only a few cases are described in the literature that too in cadavers. Recently, we came across a case of deficient pectoralis major while harvesting pectoralis major myocutaneous (PMMC) flap for reconstruction following right composite resection for carcinoma of the right buccal mucosa in a 50-year-old female. The external appearance of the anterior chest wall was normal. During surgery, we found that the clavicular head and sternal portion of the sternocostal head of the right pectoralis major muscle were absent and the costal portion of the sternocostal head was deficient over the medial aspect. A normal pectoralis minor was present. This deficiency may be congenital in nature. We present this case to highlight this uncommon condition, and this may be the only case report till now wherein deficient pectoralis major was used for PMMC flap reconstruction of oral cavity defect.