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CHAPTER 26
2. Control of incontinence
(a) Passive overflow
or passive incontinence is the result of overdistension of the para
lysed hypotonic bladder in both upper and lower motor neuron lesions, if no drainage was
established at the proper time. Rapid evacuation of an overdistended bladder by catheter
drainage should be avoided in order to give the bladder wall the chance to adjust itself to
a small volume, as otherwise haemorrhage may occur within the bladder.
Passive incontinence may also develop in tabes and diabetic neuropathy due to
degeneration of the afferent pathways when, as a result of the loss of sensibility, there is
no desire to urinate, and the bladder becomes atonic and dribbling incontinence ensues. In
progressed cases, wearing of a urinal will be indispensable in addition to intermittent
catheter drainage. In less progressed cases the treatment consists, apart from controlling
infection, in teaching the patient to adjust the frequency of micturition, using abdominal
pressure, in relation to the amount of fluid intake. Moreover, fluid intake should be
restricted from 7 p.m. and/or the patient should interrupt his sleep once or twice at
night to avoid nocturnal incontinence.
Patients with lower motor neuron lesions as a result of traumatic lesions or myelo-
dysplasia, associated with spina bifida resulting in autonomous bladder, often suffer from
passive incontinence to various degrees, especially if the sensory elements are affected
more severely than the motor, and the urethral resistance is low as a result of the paralysis
of the urethral spincter and the bulbo-cavernosus muscles, and the anal reflexes are
absent. Such patients will need urinals or, in certain cases, surgical urinary diversion,
especially in cases of spina bifida, if hydronephrosis, hydroureter or other anomalies of
the upper urinary tract exist, representing co-existent anomalies to the lower motor
neuron lesions. Nash (1967) reported on urinary diversion in congenital paraplegia in
473 children, in 448 (about 95 per cent) of whom the causative lesion was spina bifida or
dysplasia. Seventy female children have been subjected to ileal loop diversion at various
ages and various stages of their pathology. Children below the age of 5 were excluded
from this operation. The post-operative mortality was nil, 50 girls operated on between
1955-1963 were followed up. There was a late mortality due to renal failure of 7 (14 per
cent), 3 in the first 4 months, one in the 3rd year, 2 in the 4th year and one in the loth
year. Nash considered ileal loop as the most satisfactory method in dealing with incon
tinence arising from congenital paraplegia in the female. However, in incomplete lower
motor neuron lesions, whether traumatic or non-traumatic, the passive incontinence can
be reduced to manageable proportions by training the patient to habits of self-manage
ment. This can even be achieved, as I found, in spina bifida children, provided the
mother is instructed to correlate the amount of fluid intake and the time of expressing
the child's bladder to avoid dribbling incontinence.
(b) Stress.
A special form of passive incontinence in lower motor neuron lesion is the
stress incontinence due to weakness of the external urethral sphincter and the muscles of
the pelvic floor. Loss of urine will occur during various types of stresses such as coughing,
laughing, brisk movements, jumping or lifting of objects, even in patients who otherwise
have learned to control their incontinence. Such patients may, therefore, prefer to wear
a urinal.
