Slow transit constipation. Comparison between patients with or without previous hysterectomy

We have studied 31 patients with slow transit constipation. Fourteen developed severe symptoms following a hysterectomy, while the remainder had symptoms arising de novo and unrelated to pelvic surgery. To establish whether there were specific abnormalities which might be linked to hysterectomy, we compared the two groups. Rectosigmoid motility was impaired in the de novo group. Functional sphincter length, maximum resting anal canal pressure, and the rectoanal inhibitory reflex were not significantly different from controls. The majority of patients were able to significantly increase the anorectal angle on straining to defecate. Patients in the de novo group had a higher sensory threshold for rectal filling compared with controls, whereas the posthysterectomy group was not significantly different. Electromyography of the external sphincter showed failure of appropriate inhibition of resting activity in 57% of the de novo and 38% of posthysterectomy patients. The de novo group had hypoactivity of the rectosigmoid and an insensitive rectum. The abnormality in the hysterectomy group is less clear and any precise link between slow transit constipation and hysterectomy remains obscure.