Interpretation of findings
A large proportion of the existing literature on AS repairs relates to trans-perineal anterior sphincteroplasty often with no concurrent perineal body repair. The study demonstrates that, following a transvaginal repair, long-term functional results are better than previously reported in the literature. Gutierrez et al published on 182 patients undergoing an anterior sphincteroplasty without perineal body repair. 57% were still incontinent of solid stool at 10 year follow up (15). Barossa et al had 370 patients from a Danish registry with 54% still incontinent of solid stools at follow up (13). In our cohort we showed that only 26.8% of women were incontinent of solid stool at follow up. Furthermore, our study showed that 69.3% had a clinically significant improvement in their symptoms with 46.5% of patients showing a marked improvement in their incontinence. Whether this is causally related to the transvaginal route with a concurrent posterior repair is hard to determine in a retrospective observational study.
Perineal body thickness is a predictor of FI (16). It would make sense that reconstructing the perineal body with a perineorrhaphy at the time of surgery would improve continence score although further studies are needed to confirm this.
Briel et al compared complex repairs (with perineorrhaphy and restoring rectovaginal septum) vs simple repairs. This trial did not show any difference, the numbers were small and patients receiving simple repairs were done >10 yr prior to the complex repairs (17). Chase et al showed that all patients that had a levatorplasty at time of sphincter repair did well following sphincter repair, although this is based on only 6 patients (18).
We believe that a concomitant pelvic floor repair with the AS repair can improve results, as the pelvic floor and perineal body plays an important part in continence. Excessive vaginal narrowing from overtight levator sutures and introital stenosis resulting in dyspareunia in sexually active women should be avoided.
Successful anatomic repair of the defect would likely be a factor in predicting long-term functional outcomes; however, no series of long-term follow-up of patients with postoperative imaging exists (1). Engel et al compared US pre and post with a median follow up of 15 months. It showed that the postoperative squeeze pressure was increased, and the external sphincter was more frequently intact in those with a good outcome (19). In our case series, women with a persistent defect had a higher post-operative St Marks score compare to the women with no defect, but the numbers were small. Endoanal ultrasound may have the ability to identify those patients with poor results from an initial repair who may benefit from repeat repair (20).
An increasingly popular method to treat AI is with sacral neuromodulation. This has also been evaluated in women with sphincter defects. A prospective study on the efficiency of SNS for faecal incontinence following OASIS has shown that SNS can reduce weekly faecal incontinence, regardless of the extent of the sphincter defect (21). A Cochrane systematic review from 2015 showed favourable mid‐ and long‐term positive outcomes for SNS. The review reported the success rates for SNS (based on at least 50% improvement in FI episodes per week) were 63%, and 36% of participants achieved complete faecal continence. The quality of evidence was low and there was no consistent outcome reporting between studies making the analysis difficult (22). These figures may be reduced further when results are reanalysed using all available participants on an intention‐to‐treat basis. Furthermore, SNS has a high surgical revision rate of up to 32.5% for complications relating to the device such as pain and lead migration (23). A prospective comparative trial in women with sphincter defects would beneficial to help guide women and clinicians in the treatment of AI in the setting of sphincter defects.