Superficial part of external anal sphincter

The superficial part of the external anal sphincter is one of the three parts of the external anal sphincter (EAS), constituting the main portion of the muscle. It arises from a narrow tendinous band, the anococcygeal raphé, which stretches from the tip of the coccyx to the posterior margin of the anus; it forms two flattened planes of muscular tissue, which encircle the anus and meet in front to be inserted into the central tendinous point of the perineum, joining with the Transversus perinaei superficialis, the Levator ani, and the Bulbocavernosus.

The superficial part of the external anal sphincter is a striated muscle that encircles the anal canal and contributes to the voluntary control of defecation. This part of the EAS is continuous with the deep part superiorly and the subcutaneous part inferiorly, forming a crucial component of the anal sphincter complex