Editing Urinary incontinence (section)

==Mechanism==
=== Adults ===
The body stores urine—water and wastes removed by the kidneys—in the [[urinary bladder]], a balloon-like organ. The bladder connects to the [[urethra]], the tube through which urine leaves the body.<ref>{{cite journal | vauthors = Andersson KE, Arner A | title = Urinary bladder contraction and relaxation: physiology and pathophysiology | journal = Physiological Reviews | volume = 84 | issue = 3 | pages = 935–986 | date = July 2004 | pmid = 15269341 | doi = 10.1152/physrev.00038.2003 }}</ref>{{citation needed|date=April 2021}}

Continence and [[micturition]] involve a balance between [[urethra]]l closure and [[detrusor]] muscle activity (the muscle of the bladder). During [[urination]], [[detrusor muscle]]s in the wall of the bladder contract, forcing urine out of the bladder and into the urethra. At the same time, [[sphincter]] muscles surrounding the urethra relax, letting urine pass out of the body.  The [[Urethral sphincters|urethral sphincter]] is the muscular ring that closes the outlet of the urinary bladder preventing urine to pass outside the body. Urethral pressure normally exceeds bladder pressure, resulting in urine remaining in the [[Urinary bladder|bladder]], and maintaining continence.<ref>{{cite journal | vauthors = DeLancey JO | title = Anatomy and physiology of urinary continence | journal = Clinical Obstetrics and Gynecology | volume = 33 | issue = 2 | pages = 298–307 | date = June 1990 | pmid = 2190733 | doi = 10.1097/00003081-199006000-00014 | s2cid = 43806356 }}</ref> The urethra is supported by [[Pelvic floor|pelvic floor muscles]] and tissue, allowing it to close firmly. Any damage to this balance between the [[detrusor muscle]], [[Urethral sphincters|urethral sphincter]], supportive tissue and nerves can lead to some type of incontinence .{{citation needed|date=April 2021}}

For example, [[Stress incontinence|stress urinary incontinence]] is usually a result of the incompetent closure of the urethral sphincter. This can be caused by damage to the sphincter itself, the muscles that support it, or nerves that supply it. In men, the damage usually happens after prostate surgery or radiation,<ref name="Clemens_2022" /> and in women, it's usually caused by childbirth and pregnancy.<ref>{{cite journal | vauthors = DeLancey JO | title = The pathophysiology of stress urinary incontinence in women and its implications for surgical treatment | journal = World Journal of Urology | volume = 15 | issue = 5 | pages = 268–274 | date = 1997-10-01 | pmid = 9372577 | doi = 10.1007/BF02202011 | hdl-access = free | s2cid = 12952663 | hdl = 2027.42/47055 }}</ref> The pressure inside the abdomen (from coughing and sneezing) is normally transmitted to both urethra and bladder equally, leaving the pressure difference unchanged, resulting in continence. When the sphincter is incompetent, this increase in pressure will push the urine against it, leading to incontinence.{{citation needed|date=April 2021}}

Another example is urge incontinence. This incontinence is associated with sudden forceful contractions of the [[detrusor muscle]] (bladder muscle), leading to an intense feeling of urination, and incontinence if the person does not reach the bathroom on time. The syndrome is known as [[Overactive bladder|overactive bladder syndrome]], and it's related to dysfunction of the detrusor muscle.<ref>{{Cite web|title=Overactive Bladder (OAB): Symptoms, Diagnosis & Treatment | work = Urology Care Foundation |url= https://www.urologyhealth.org/urologic-conditions/overactive-bladder-(oab) |access-date=2020-05-08}}</ref>

===Children===
[[File:Voiding dysfunction.svg|thumb|upright=1.6|Voiding dysfunction]]
{{main|Enuresis}}
Urination, or voiding, is a complex activity. The bladder is a balloon-like muscle that lies in the lowest part of the abdomen. The bladder stores urine and then releases it through the urethra, which is the canal that carries urine to the outside of the body. Controlling this activity involves nerves, muscles, the spinal cord and the brain.{{citation needed|date=April 2021}}

The bladder is made of two types of muscles: the detrusor and the sphincter. The detrusor is a muscular sac that stores urine and squeezes to empty. Connected to the bottom or next of the bladder, the sphincter is a circular group of muscles that automatically stays contracted to hold the urine in. It will automatically relax when the detrusor contracts to let the urine into the urethra. A third group of muscles below the bladder (pelvic floor muscles) can contract to keep urine back.{{citation needed|date=April 2021}}

A baby's bladder fills to a set point, then automatically contracts and empties. As the child gets older, the nervous system develops. The child's brain begins to get messages from the filling bladder and begins to send messages to the bladder to keep it from automatically emptying until the child decides it is the time and place to void.{{citation needed|date=June 2022}}

Failures in this control mechanism result in incontinence. Reasons for this failure range from the simple to the complex.{{citation needed|date=June 2022}}