Primary repair of obstetric anal sphincter rupture using the overlap technique

Abstract

Objective: To evaluate the feasibility of a new technique of primary overlap anal sphincter repair instead of end-to-end repair.

Setting: A teaching hospital and a district general hospital.

Methods: Between June 1995 and November 1996, two obstetricians repaired 32 anal sphincters ruptured during vaginal delivery. A ruptured internal sphincter was repaired separately and the torn ends of the external sphincter were overlapped and sutured with 3/0 polydioxanone sulphate sutures (Ethicon, Edinburgh, UK).

Main outcome measures: Bowel function, clinical assessment, anal endosonography and manometry performed at a mean of 140 days after delivery.

Results: Eight percent of the women experienced incontinence of flatus. Fifteen percent had persistent sonographic external sphincter defects, and 44% had internal sphincter defects. The maximum mean resting pressure was 58 mmHg (range 37-135) and the mean maximum incremental squeeze pressure 54 mmHg (range 8-104). None had defaecatory difficulty and no complications were encountered with the new technique of repair.

Conclusions: Reservations regarding the feasibility of the overlap technique of primary repair are unfounded, as both subjective and objective outcomes are favourable compared with other studies using end-to-end approximation. A multicentre randomised study of the overlap vs end-to-end repair technique is now planned.