An Unusual Bilateral Membranous Variant of Triplicate Pitted Pectoralis Major Muscle: A Case Report

The variations in the attachments of the pectoralis major not only affect its function but also reflect on its ability to be used as flaps. Membranous origins of this muscle not only add to its stress but also contribute to its inherent tears. The present report unravels the membranous as well as variant tri-muscular origins of this muscle bilaterally, with implications for its role in reconstructive procedures. Although varied classifications of this muscle exist in the literature, the present case finding is unique due to the gaps of separation that were found between the strata of this muscle, which is quite a rare phenomenon. Variations in the membranous and triplicate origins of the pectoralis major are indeed rare findings that warrant the need for larger, separate morphological typing studies in order to delineate its intricate patterns. Membranous variants of the pectoralis major are prone to shearing stress and internal tears, which pose threats to flap reconstruction procedures involving this muscle; thus, the present case report represents a significant finding.