A prospective study of the effect of haemorrhoidectomy on sphincter function and faecal continence.

The effect of haemorrhoidectomy on anal sphincter manometry and continence to faeces and rectally infused saline was investigated in 24 unselected patients with third-degree haemorrhoids. Haemorrhoidectomy resulted in the abolition of ultra-slow waves and significant decreases in basal and squeeze pressures, though these were reduced to normal values from abnormally high levels. Pressures remained at normal levels up to a year after surgery. An association was found between mucous soiling following surgery and an abnormally low postoperative squeeze pressure. There was no alteration in the function of the recto-anal inhibitory reflex following surgery. Only two patients developed incontinence to rectally infused saline for the first time following surgery. The addition of four-finger dilatation of the anal canal to the operative procedure did not cause any significant differences in sphincter manometry.