Short- and long-term outcomes of sphincteroplasty for anal incontinence related to obstetric injury: a systematic review.

Anal incontinence is a frequent pathological condition with devastating impact on quality of life. The prevalence is approximately 15% of the population, with higher incidence reported in the elderly and multiparous women, and several factors have a major role in its pathogenesis, such as anatomical sphincter defects (Glasgow and Lowry in Dis Colon Rectum 55(4): 482-490, 2012), delivery injuries, and colorectal, uro-gynecological, and perineal surgery. The direct surgical approach is the gold standard treatment for fecal incontinence, especially through anterior sphincteroplasty, although a permanent defect of continence persists over time. The aim of our study is to evaluate, throughout a systematic review of the literature, the short- and long-term outcomes of sphincteroplasty performed for obstetric injuries anal incontinence. A systematic review of the studies published in the literature from January 2000 to December 2021 was performed in accordance with the PRISMA guidelines. Of the 2543 studies extrapolated, only eight fulfilled the inclusion criteria and were admitted represented by retrospective and prospective studies. The data analyzed from the included studies were number and mean age of the female population, and incontinence improvement with preoperative and postoperative short- and long-term outcomes, as reported by QoL questionaries and incontinence scores. Overall 355 patients with obstetric sphincter damage underwent sphincteroplasty with an anterior external sphincter overlapping procedure. A consistent improvement in fecal incontinence at short-term follow-up with relative improvement in QoL was reported. In 7 of 8 studies, the authors found a progressive worsening of the incontinence symptoms on the long-term follow-up. However, it is not clear whether the decrease in long-term continence results is parallel to a simultaneous decrease in QoL scores. Nevertheless, compared to the preoperative findings, the improvement was maintained in the long-term follow-up. Despite the limited data in the literature, a properly performed sphincteroplasty can guarantee a consistent improvement of the continence in short term with encouraging outcomes, especially for solid stool continence, in long time. We believe that anterior sphincteroplasty, as a low cost, feasible, and safe procedure, still has a role in the treatment of fecal incontinence for obstetric injury. Further large cohort randomized clinical trials are necessary to validate these results.