Anorectal function in patients with complete rectal prolapse. Differences between continent and incontinent individuals

Abstract

Aims: A study is made of the alterations in anorectal physiology among rectal prolapse patients, evaluating the differences between fecal continent and incontinent individuals.

Patients and methods: Eighteen patients with complete rectal prolapse were divided into two groups: Group A (8 continent individuals) and Group B (10 incontinent women), while 22 healthy women were used as controls (Group C). Clinical exploration and perineal level measurements were performed, along with anorectal manometry, electrophysiology, and anorectal sensitivity to electrical stimuli.

Results: The main antecedents of the continent subjects were excess straining efforts, while the incontinent women presented excess straining and complex deliveries. Pathological perineal descent was a frequent finding in both groups, with a hypotonic anal canal at rest (p < 0.001 vs controls) and at voluntary squeezing (p < 0.001 vs controls). In turn, the incontinent patients exhibited a significantly lower anal canal pressure at rest than the continent women (p < 0.05). There were no significant differences between Groups A and C in terms of pudendal motor latency, though latency was significantly longer in Group B than in the controls (p < 0.01). Moreover, pudendal neuropathy was more common, severe and often bilateral in Group B. There were no differences in rectal sensation to distention or in terms of the volumes required to relax the internal anal sphincter. In turn, both prolapse groups exhibited diminished anal canal and rectal sensitivity to electrical stimuli.

Conclusions: Patients with rectal prolapse exhibit a hypotonic anal canal at rest, regardless of whether they are continent to feces or not. Continent patients have less pudendal neuropathy and therefore less pressure alterations at voluntary sphincter squeeze than incontinent individuals.