Which structure is NOT contained in the anal triangle?

Which structure is NOT contained in the anal triangle?

• A. Lower anal canal
• B. Anococcygeal body
• C. Bilateral ischiorectal fossae
• D. Ischiocavernosus muscle

Answer: (D)

The anal triangle contains structures associated with the anal canal and posterior perineum, including the lower anal canal with its sphincters, the anococcygeal body in the midline, and the bilateral ischiorectal fossae lying lateral to the canal. The ischiocavernosus muscle, however, is part of the urogenital triangle. It lies over the ischiopubic ramus and around the crus of the penis or clitoris, not within the posterior anal region. Therefore, the ischiocavernosus muscle is not contained in the anal triangle.

The anal triangle contains structures associated with the anal canal and posterior perineum, including the lower anal canal with its sphincters, the anococcygeal body in the midline, and the bilateral ischiorectal fossae lying lateral to the canal. The ischiocavernosus muscle, however, is part of the urogenital triangle. It lies over the ischiopubic ramus and around the crus of the penis or clitoris, not within the posterior anal region. Therefore, the ischiocavernosus muscle is not contained in the anal triangle.