Direct repair vs. overlapping sphincter repair: a randomized, controlled trial

Abstract

Purpose: The aim of this study was to compare the results of two surgical techniques (direct end-to-end vs. overlapping) of delayed repair of a localized anterior defect of external anal sphincter after an obstetric trauma.

Methods: During a five-year period, 23 patients were randomly assigned to direct end-to-end repair (n = 12) or overlapping sphincter repair (n = 11), using 2-0 PDS sutures. Two patients from each group had an internal anal sphincter defect that also was repaired. All patients had a normal pudendal nerve terminal motor latency preoperatively. Evaluations included endoanal ultrasound, anorectal manometry, and neurophysiologic evaluation. Continence was assessed by the Cleveland Clinic Continence Score (0-20; 0, perfect continence; 20, complete incontinence).

Results: The two groups were comparable with regard to age (median, 45 years), past history of sphincter repair (n = 2), and posterior vaginal repair. There was no major morbidity. The wound-healing rate was identical between the two groups. However, of the patients undergoing overlapping repair, two had fecal impaction, and one had a urinary retention. Median preoperative continence score was 17 in both the direct-repair group (score, 8-20) and the overlap group (score, 7-20). At a median follow-up of 18 months, the improvement in continence was similar between the two surgical groups, with a median continence score of 3, respectively. In both surgical groups there was a significant and similar improvement in maximum squeeze pressure and in the functional anal canal length postoperatively (P < 0.05), but the mean resting pressure was relatively unchanged. In the overlap group, one patient developed a unilaterally prolonged pudendal nerve terminal motor latency that was persistent 22 months after surgery, and two patients had impaired fecal evacuation postoperatively.

Conclusions: This randomized, controlled study suggests that the outcome is similar whether direct end-to-end or overlapping repair of a sphincter defect is performed. Overlapping repair might be associated with more difficulties with fecal evacuation and a prolonged pudendal nerve terminal motor latency postoperatively.