Preoperative anal manometry predicts continence after perineal proctectomy for rectal prolapse

PURPOSE: This study examines whether preoperative anal manometry and pudendal nerve terminal motor latency predict functional outcome after perineal proctectomy for rectal prolapse. METHODS: All adult patients treated by perineal proctectomy for rectal prolapse from 1995 to 2004 were identified (N = 106). Forty-five patients underwent anal manometry and pudendal nerve terminal motor latency testing before proctectomy and they form the basis for this study. RESULTS: Perineal proctectomy with levatoroplasty (anterior 88.9 percent; posterior 75.6 percent) was performed in all patients, with a mean resection length of 10.4 cm. Four patients (8.9 percent) developed recurrent prolapse during a 44-month mean follow-up. Preoperative resting and maximal squeeze pressures were 34.2 ± 18.3 and 60.4 ± 30.5 mmHg, respectively. Pudendal nerve terminal motor latency testing was prolonged or undetectable in 55.6 percent of patients. Grade 2 or 3 fecal incontinence was reported by 77.8 percent of patients before surgery, and one-third had obstructed defecation. The overall prevalence of incontinence (77.8 vs. 35.6 percent, P < 0.0001) and constipation (33.3 vs. 6.7 percent, P = 0.003) decreased significantly after proctectomy. Patients with preoperative squeeze pressures >60 mmHg (n = 19) had improved postoperative fecal continence relative to those with lower pressures (incontinence rate, 10 vs. 54 percent; P = 0.004), despite having similar degrees of preoperative incontinence. Abnormalities of pudendal nerve function and mean resting pressures were not predictive of postoperative incontinence. CONCLUSIONS: Perineal proctectomy provides relief from rectal prolapse, with good intermediate term results. Preoperative anal manometry can predict fecal continence rates after proctectomy, because patients with maximal squeeze pressures >60 mmHg have significantly improved outcomes.