Sonographic detection of puborectalis muscle avulsion is not associated with anal incontinence

Background: The puborectalis muscle is believed to play an important role in anal continence. However, to date, there is very limited evidence to support this hypothesis. Aims: This study was designed to test for an association between puborectalis trauma and ballooning of the levator hiatus on the one hand and anal incontinence on the other hand. Methods: The records of 397 women who had attended a tertiary urogynaecological clinic were reviewed in a retrospective study. The history included questions on faecal urgency, soiling, faecal and flatus incontinence. Examination included puborectalis muscle assessment by palpation and 4D pelvic floor ultrasound. Results: Mean age on presentation was 54 (19-89) years. Median vaginal parity was 2 (0-9). Of 397 women, 89 complained of faecal urgency, 65 of faecal incontinence (FI), 67 of soiling and 91 of flatus incontinence. Seventy-seven patients were diagnosed with puborectalis avulsion, of which 38 were bilateral. Puborectalis avulsion was not associated with FI (P = 0.801), faecal urgency (P = 0.894), soiling (P = 0.768) and flatus incontinence (P = 0.187). Hiatal dimensions at rest or on Valsalva were also found not to be associated with symptoms of anal incontinence. Conclusions: Surprisingly, we found no association between avulsion of the puborectalis muscle and hiatal biometry on the one hand and anal continence on the other hand. These findings argue against a major role of the puborectalis muscle in anal continence.