Perineal nerve damage in genuine stress urinary incontinence. An electrophysiological study.

Twelve patients with genuine stress incontinence of urine were investigated using manometric and electrophysiological techniques. All were shown to have slowed conduction in the perineal branch of the pudendal nerve which innervates the periurethral striated sphincter muscle. The mean perineal nerve terminal motor latency in these patients was 3.9 +/- 0.8 (ms) and in 20 age and parity matched control subjects was 2.0 +/- 0.2 (ms) (P less than 0.001). These results are consistent with a neurogenic factor in patients with genuine stress incontinence of urine which may have implications regarding selection of patients for surgery to restore urethral competence.