The ischiopubic ramus is a compound structure consisting of the following two structures: from the pubis, the inferior pubic ramus from the ischium, the inferior ramus of the ischium It serves as part of the origin for the Obturator internus muscle. It also marks a vertex of the anal triangle and the urogenital triangle. The fascia of Colles is attached to its margin. [ http://en.wikipedia.org/wiki/Ischiopubic_ramus ]