Introduction
Anal incontinence (AI) is a very distressing condition that occurs in up to 15% of women (1) However the true incidence is likely to be higher as only a third of women with incontinence ever report this to their physician (2). Disruption of the anal sphincter caused by obstetric injury (Obstetric anal sphincter injury (OASI)), or anorectal operations are the most common causes of AI (3). It is estimated that 51% of patients reported some degree of AI following OASI (4). Third-degree tears occur during 2-6 % of vaginal deliveries and are usually repaired by obstetrician-gynaecologists, but “occult” sphincter injury that are unrecognized at delivery may occur in up to one-third of deliveries (5). AI following childbirth may result from sphincter damage or nerve injury, or both (6).
The most common finding is a defect in the anterior external anal sphincter, which often manifests clinically as urgency of defecation and faecal urge incontinence. Associated disruption of the internal sphincter may cause additional symptoms of passive or stress AI (7).
Conservative therapies (stool bulking agents, antidiarrheals and pelvic floor exercises/biofeedback) are the mainstay of initial treatment, with reported improvement of up to 80% (8). When conservative treatment fails, a sphincteroplasty or sacral nerve stimulation are commonly offered. Most reports on AS repair for faecal incontinence in the literature are uncontrolled case series mostly using the trans-perineal approach. There are very few studies comparing sphincteroplasty with other treatments.
Short term success rates for anal sphincter repair are up to 80%. This reduces to 50% when patients were followed up for more than 5 years in a systematic review (1). In asymptomatic females, aging is associated with reduced anal resting and squeeze pressures, reduced rectal compliance, reduced rectal sensation, and perineal laxity (9).
Although AI deteriorates over the long-term following anal sphincteroplasty, patient QOL and satisfaction with improved control remain relatively high (1).
Prognostic factors associated with less favourable outcomes include advanced patient age, longer duration of incontinence and postoperative wound infection (10).
Over recent years there has been a number of changes and improvements, particularly in diagnostic techniques using ultrasound imaging of the AS. There has also been an introduction of other novel treatments such as Sacral Neuromodulation and Anal Bulking which have led to a decline in this procedure partly due to its poor long-term results in the current literature.
The objective of our study was to examine the long-term functional outcomes following transvaginal anal sphincter repair for faecal incontinence.