PUDENDAL NERVE-TERMINAL MOTOR LATENCY INFLUENCES SURGICAL OUTCOME IN TREATMENT OF RECTAL PROLAPSE

PURPOSE: This study was undertaken to document the effect of pudendal nerve function on anal incontinence after repair of rectal prolapse. M ETHODS: Patients with full rectal prolapse (n = 24) were prospectively evaluated by anal manometry and pudendal nerve terminal motor latency (PNTML) before and after surgical correction of rectal prolapse (low anterior resection (LAR; n = 13) and retrorectal sacral fixation (RSF; n = 11)). RESULTS: Prolapse was corrected in all patients; there were no recurrences during a mean 25-month follow-up. Postoperative PNTML was prolonged bilaterally (>2.2 ms) in six patients (3 LAR; 3 RSF; fiv e patients were incontinent (83 percent). PNTML was prolonged unilater ally in eight patients (4 LAR; 4 RSF); three patients were incontinent (38 percent). PNTML was normal in five patients (3 LAR; 2 RSF); one w as incontinent (20 percent). Postoperative squeeze pressures were sign ificantly higher for patients with normal PNTML than for those with bi lateral abnormal PNTML (145 vs. 66.5 mmHg; P = 0.0151). Patients with unilateral abnormal PNTML had higher postoperative squeeze pressures t han those with bilateral abnormal PNTML, but the difference was not si gnificant (94.8 vs. 66.5 mmHg; P = 0.3182). The surgical procedure did not affect postoperative sphincter function or PNTML. CONCLUSION: Inj ury to the pudendal nerve contributes to postoperative incontinence af ter repair of rectal prolapse. Status of anal continence after surgica l correction of rectal prolapse can be predicted by postoperative meas urement of PNTML.