What is the pelvic floor?

Pelvic floor function is very important in the maintenance of both bladder and bowel continence.

The pelvic floor is a funnel-shaped structure. It is a sling of muscles and ligaments which support the organs in the lower pelvis, the bladder and bowel, and in females the vagina. The sling is attached to the pubic bone at the front and the coccyx at the back.

To understand the structure of the pelvic floor it is helpful to look at it diagrammatically:

^{Above: the pelvic organs and pelvic floor muscles}

The diagram above shows the sling of pelvic floor muscles and it demonstrates the relationship with the bladder/vagina/rectum in the female.

How does the pelvic floor work?

When the pelvic floor contracts, the internal organs are lifted and the sphincters and opening to the vagina, urethra and anus tighten. When the pelvic floor relaxes this allows for the passage of urine and faeces.

The pelvic floor is also important for sexual function in both sexes, in men for erectile function and ejaculation, and in females a voluntary contraction contributes to sexual sensation and arousal.

The diagram below shows a bird’s eye view of the pelvic floor of a female:

^{Above: ‘Bird’s eye view’ of the pelvic floor muscles of a female.}

From this view (above), the pelvic floor looks like a ‘pudding basin’ and the three openings in the pelvic floor — the urethral hiatus, the vaginal canal and the rectal hiatus — can clearly be seen.

It also shows the position of the main pelvic floor muscles — the puborectalis, the pubococcygeus, the iliococcygeus and the coccygeus.

The urogenital hiatus is an anteriorly positioned gap which allows for the passage of the urethra in males and the urethra and vagina in females, therefore allowing for urination.

The rectal hiatus is a posteriorly positioned gap which allows for the passage of the anal canal, therefore allowing defaecation.