Among 1,972 patients operated upon because of lumbar disc herniation in a 7-year period (1971-1978), cauda equina syndrome was diagnosed in 26 patients. 22 patients had follow-ups 4-72 months postoperatively (average 37 months). At follow-up half of the patients had histories of normal micturition and only 6 patients made serious micturition complaints. One third were free from lumbar or sciatic pain, two thirds complained of distressing pain and neurological symptoms. The urodynamic investigation revealed complete bladder emptying in all but 1 patient. In half of the patients normal detrusor contraction was demonstrated, while one third of the patients voided by straining only. Preoperative micturition symptoms exceeded 2 days in almost all patients voiding by straining. This finding indicates a connection between early diagnosis and treatment, and the degree of detrusor damage.