The anatomy of urination: What every physician should know

Normal voiding needs a coordinated, sustained bladder contraction of adequate size and duration. It requires a decrease in resistance of the bladder neck and urethra and no obstruction. Voiding problems can arise from abnormal storage of urine or problems with urinary control. The aim of this article was to review the functional anatomy and physiology of urinary control and micturition and the pathophysiology of urinary control problems. The Medline (PubMed) database, Cochrane Library, and Science Citation Index were searched electronically to identify original published studies on bladder anatomy, function and urinary control. References were searched from relevant chapters in specialized texts and all were included. Voiding problems are the most common presenting urological symptoms in general medical practice. Urinary incontinence occurs when the normal process of storing and passing urine is disrupted. A history of coexisting fecal incontinence suggests a neuropathic etiology. A better understanding of the physiology of urinary control could lead to preventive measures for postoperative urinary retention and incontinence such as fluid restriction and to appropriate anesthesia/analgesia, autonomic nerve preservation, total mesorectal excision (TME) for rectal cancer, and biofeedback exercises. It could also suggest appropriate therapeutic measures for established urinary incontinence. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.