The pelvic floor is a complex trampoline-like structure made up of muscle and ligaments. It acts like a scaffolding for the anus, rectum, bladder and vagina. Specialised parts of the pelvic floor act as sphincters (gatekeepers) helping to maintain anal and urinary continence. Part of the pelvic floor forms a sling around the anorectal junction (where the rectum joins the anus) and helps to preserve anal function and facilitate defaecation by altering the angle between the anus and rectum at the appropriate time.