Anatomical observations on 30 cadavers: new insights into the relationship between the posterior wall of the inguinal canal and the cremaster.

ABSTRACT

PURPOSE: Clarify the composition of the Posterior wall of the Inguinal Canal(PWIC), the location and composition of the Transverse Fascia(TF), and the tissue origin of the Cremaster(C) by observing the anatomy of the inguinal region of the cadaver. METHODS: 30 cadavers were dissected to observe the alignment of the muscles and fascia of the inguinal canal and the anterior peritoneal space. the anatomical levels of the posterior wall of the inguinal canal and the alignment of the Spermatic Cord(SC) were observed. RESULTS: (1) The posterior wall of the inguinal canal was white, bright, and tough tendon membrane-like tissue; (2) the transverse fascia was a thin fascial tissue with only one layer of membranous structure located in the abdominal wall under the abdominal wall on the side of the blood vessels of the peritoneal cavity; (3) the internal oblique muscle and its tendon membrane, and the transversus abdominis muscle and its tendon membrane extended on the surface of the spermatic cord, and fused and continued to the cremaster on the surface of the spermatic cord. CONCLUSIONS: 1. PWIC is mainly composed of Internal oblique muscle of abdomen (IOMA), Aponeurosis of internal oblique muscle of abdomen (AIOMA), Transverse abdominal muscle (TAM), and Transverse abdominal aponeurosis(TAA) as the following four types (1) TAM and AIOMA fused to form a tendinous layer; (2) IOMA and TAM form the posterior wall of the muscle in the PWIC; (3) IOMA and AIOMA continue in the PWIC; 4) TAM and TAA continue in the PWIC. 2.TF is a thin fascial tissue with only one layer of membrane structure, TF is not involved in the composition of PWIC, so this fascia has nothing to do with resisting the occurrence of inguinal hernia. 3. The spermatic cord that travels in the inguinal canal is fixed to the lower wall of the inguinal canal by the tendon membrane of the cremaster, which is organized from the internal oblique and transversus abdominis muscles and their tendon membranes, The inguinal canal is a musculotendinous canal.