What is the course of an indirect hernia?

The course of an indirect hernia is indeed through the internal inguinal ring, down the inguinal canal, and into the scrotum. This pathway occurs due to the hernia sac passing through the deep inguinal ring, which is a congenital defect in the transversalis fascia.

Indirect inguinal hernias are the most common type of hernias among infants and are typically associated with a failure of the processus vaginalis to close. As a result, abdominal contents can move from the abdominal cavity through the inguinal canal and into the scrotum, especially during activities that increase intra-abdominal pressure, such as lifting or straining.

In comparison, the other pathways mentioned relate to different types of hernias or incorrect anatomical routes. The external inguinal ring at Hesselbach's triangle corresponds to direct inguinal hernias, while a hernia passing directly through the abdominal wall does not typically indicate an indirect hernia. Lastly, a route directly into the peritoneal cavity without passing through any rings would not describe an inguinal hernia scenario.