STUDIES ON TERMINAL MOTOR LATENCY IN THE SACRAL NERVE FOR RECTOCELE

To clarify neurological function with respect to puborectalis muscle for rectocele with symptoms such as incomplete evacuation, difficulty in defecation, chronic constipation, soiling, and so on, we examined terminal motor latency in the sacral motor nerves (SNTML). The latency of the response in the puborectalis muscle following transcutaneous stimulation of the spinal column overlying the cauda equina was measured. SNTML was measured in 34 patients with rectocele (females, age 24-79 years, mean age 55.4 years), and the results were compared with data obtained from 10 control subjects (females, age 16-66 years, mean age 49.9 years). Incomplete evacuation and defecation straining were the most common complaint in the patients with rectocele, and they were significantly more common in patients with rectocele compared with normal subjects. Most rectocele cases had a history of childbirth. In 44% of the patients, rectocele was associated with perineal descent. The conduction delay of bilateral SNTML in the patients with rectocele was longer than that in the control subjects. These findings support the hypothesis that the conduction delay of SNTML in rectocele patients is caused by damage (stretch injury, entrapment, and so one) to sacral motor nerves.