Sphincters in our body keep the urethra closed preventing leakage of urine when the bladder is not full or when you do not want to urinate. Internal sphincters are located at the neck of the bladder and the external sphincters are located below the prostate gland. Urinary incontinence is the leakage of urine when you do not intend to urinate. This condition is more common in women than men, but men can also have it.

Urination is a complex process controlled by muscles of the bladder and urinary sphincter mechanism and by modulatory centers in the central and peripheral nervous systems.

The illustration shows the nervous control of the urinary bladder through the hypogastric, pelvic and pudendal nerves in a human body.

An illustration showing enlarged view of urinary catheterization in a patient.

A Foley catheter is used with many disorders, procedures, or problems such as enlarged prostate, retention of urine, prostate cancer, trauma etc. It is a thin, sterile tube inserted into the bladder to drain urine.