Anismus as a marker of sexual abuse. Consequences of abuse on anorectal motility.

Anorectal manometry was performed in 40 women, who consulted for functional disorders of the lower gastrointestinal tract and had been sexually abused. Anismus, defined as a rise in anal pressure during straining, was observed in 39 of 40 abused women, but in only six of 20 healthy control women (P < 0.0001). Other parameters of anorectal manometry were compared with those observed in another control group composed of 31 nonabused women but with anismus, as well as the group of healthy controls. A decreased amplitude of anal voluntary contraction and an increased threshold volume in perception of rectal distension were observed in both abused and nonabused patients. A decreased amplitude of rectoanal inhibitory reflex, little rise in rectal pressure upon straining, frequent absence of initial contraction during rectal distension, and increased resting pressure at the lower part of the anal canal were observed in abused but not in nonabused patients, suggesting that these abnormalities, in association with anismus, suggest a pattern of motor activity in the anal canal that could be indicative of sexual abuse.