96 Neurological bladder
Salient features
Examination
Ask the patient the following questions:
• Do you get a sensation when the bladder is full?
• Do you feel the urine passing?
• Are you able to stop urine passing in midstream at your own will?
• Does the bladder leak continually?
• Do you suddenly pass large volumes?
• The examination should concentrate on the legs, because the segments that innervate the bladder are caudal to those that innervate the lower limbs, and spinal cord involvement that affects the innervation of the bladder almost always results in lower limb signs. (Possible exceptions are lesions of the low sacral cord or conus, but only the most caudal lesions fail to produce some overactivity in the legs and extensor plantar responses.)
• Tell the examiner that in male patients you would like to take a history of impotence and examine the neurological system and spine.
Note: Cauda equina lesions at S1 and S2 may impair the ankle reflexes, and those at S3 may affect the intrinsic muscles of the foot, causing foot deformities and fasciculation of the muscles. Saddle anaesthesia is a feature of cauda equina (p. 331) or conus medullaris lesions (p. 332).
