Anatomy of the lower UT
The bladder is a hollow muscular organ situated behind
the pubic symphasis & covered superiorly & anteriorly
by peritoneum.
It is composed from a meshwork of smooth muscle
fibers which is called detrusor muscle & those fibers are
only recognized at the bladder outlet as 3 distinct layers
,the outer are longitudinal , middle circular & inner
longtudinal.
In the adult female the urethra is a muscular tube
3-5 cm in length , lined proximally by transitional
epithelium & distally by stratified sequamus non
keratinized epithelium.
The second layer is a rich vascular plexus which
contribute to the urethral pressure & it decreases
with age.
The 3rd layer is the layer of longitudinally arranged
smooth muscle fibers
The internal urethral sphincter
Is a striated m. that surround the middle one third of
the urethra & is responsible for urethral closure of
The external urethral sphincter
Is a striated m. fibers which is a part of levator ani m.
& is situated at the junction of the middle & lower one
third of urethra & it is responsible for the additional
closure pressure at time of physical effort.
The urethra is supported by 2 pubourethral
ligaments that attach the urethra to the posterior
aspect of symphasis pubis.
Innervations
The lower UT is under the control of both
sympathetic & parasympathetic system.
the parasympathetic fibers originate from the spinal
segments S2,3,4 & stimulation of those fibers will
cause contraction of detrusor m.
stimulation of these fibers occur due to sensory
impulses transmitted through strech receptors within
the bladder wall & afferent impulses from the bladder
will travel through pelvic hypogastric nerves to the
sacral spinal segments
so cholinergic drugs stimulate & anticholinergic drugs
inhibit detrusor contraction.
the sympathetic innervation is through fibers that
originate from spinal cord segments T10-L2
the sympathetic system has α & β adrenergic
component .
the β fibers terminate primerly in the detrusor m.
whereas α fibers in the urethra.
α adrenergic stimulation contract the bladder neck &
urethra & relaxes detrusor m. while β adrenergic
stimulation relaxes the detrusor m. & urethra.
The intrinsic urethral sphincter m. is supplied by
motor innervation through motor nerves from S2,3,4
via pelvic splanchnic nerves , while extrinsic urethral
sphincter m. is supplied by the same sacral nerves
roots but those travel through pudendal nerve.
Sensory supply
the afferent impulses from the bladder wall & proximal
urethra travel through pelvic hypogastric nerves to
the sacral segments S2,3,4.
the sensory nerves are stimulated when there is
increase in the intravasical pressure or acute cystitis
(radiation, infections…
Inhibitory impulses to those nerves travel through
pudendal nerve which supply sensation to the vulva
& perinael area & this is why pain in this area causes
retention of urine.
Central nervous system
During infancy , the storage & expulsion of urine is
under the direct sacral reflex arc, later on with
training there will be a central control of this reflex
arc & voiding will be under voluntary control.
This central control may be interrupted by organic
diseases , social or mental disorders.
Continence control
Normally the urine remain within the bladder as long
as the inravasical pressure is below the intraurethral
pressure & whenever the intravasical pressure
exceeds the intraurethral
pressure there will be incontinence of urine.
The pubourethral ligaments & surrounding fascia
support the proximal urethra which is normally an
intra abdominal organ, so any increase in the intra
abdominal pressure would be transmitted equally to
the bladder & urethra & the pressure gradient
remain the same.
whenever there is physical effort that increase the
intra abdominal pressure , there will be voluntary
contractions of pelvic floor m. which add additional
strength for urethral closure pressure.
It is the involuntary loss of urine
According to symptomatology the types of urinary
incontinence are:
1.
Stress inco.
2.
Total inco.
3.
Urge inco.
4.
Overflow inco.
Causes
 Genuine stress inco. (GSI) due to urethral sphincter
incompetence.
 Detrusor instability (DI)
 Retention with overflow
 Fistulae: vasico-vaginal, uretro-vaginal, urethrovaginal
 Congenital abnormality as epispadias , ectopic ureter
, spina bifida
 Urethral diverticulum
 Temporary as in UTI immobility , feacal impaction
 functional
Usually 90% of inco. In female are due to genuine
stress inco. then detrusor instability
Urinary inco. Is a symtom or eve a sign but not a
diagnosis so we need to reach to the final diagnosis
or the cause
History:
 Ask about other urinary symptoms as irritative
symptoms (dysurea , frequency, urgency) or voiding
problems (poor stream, straining during voiding,
incomplete bladder evacuation) .
 Ask about other gynecological symptoms or
diseases as prolapse, menstrual disturbance , H/O
fibroid , any gyn. operations vaginal wall repair




Obstetric history as delivery of large baby vaginaly.
If there is H/O recurrent UTI or acute retention of
urine or nocturnal enuresis during childhood.
Ask about neurological symptoms & other medical
disorder as multiple sclerosis or DM
Ask about drug intake as diuretic in old people ,
tricyclic antidepressant , major tranquilizer & β
blocker.
examination
Unfortunately clinical examination is not so helpful in
the diagnosis of female
SI can be demonstrated objectively but even that the
diagnosis can not be made with sure because 98%
of patient with GSI presented with SI , while 25% of
patients with DI can be presented with such
symptom
nevertheless the patient should be examined
generally & for mental state
local pelvic examination include inspection of vulva to
see any excoriation which indicate severity of the
condition, any atrophic change
then inspection of the vaginal wall with Sims
speculum for visualization of the anterior
vaginal wall & vasico-urethral junction & to see if
there is any scarring or rigidity due to previous
vaginal operation, & to see if there are atrophic
changes of the vaginal wall & distal urethra.
During pelvic examination stress test should be
performed that the patient in lithotimy with full
bladder , then ask the patient to cough
GSI is suspected if there is a short spurt of urine per
urethra with each cough , while if there is a delayed
leakage or loss of a large volume of urine this may
suggest DI.
If leakage of urine is not demonstrated in the
lithotomy position , then the test is repeated while the
patient in standing position.
if SI is demonstrated then GSI can be suggested by
performing Bonney’s test by inserting one finger on
each side of the urethra at the bladder neck to
elevate the bladder neck & proximal urethra , then if
urine leakage is stopped this will suggest GSI
Investigations
Simple types:
 Mid stream urine for culture & sensitivity ( the
presence of infections may affect the management )
 Frequency-volume chart
 Pad weighing test for confirmation of inco. Not for
identification the cause
 Q tip test