Anorectal and bladder function after sacrifice of the sacral nerves

Study Design. The quantitative changes in anorectal and bladder functions after sacrifice of the sacral nerves were assessed. Objectives. To evaluate the bladder and anorectal functions before and after sacral nerve division in patients with sacral bone tumors. Summary of Background Data. The quantitative changes in bladder and anorectal functions after sacrifice of the sacral nerves have not been intensively studied. The purpose of this investigation was to measure the bladder and anorectal function before and after sacral nerve division using manometry and cystometry. Methods. Surgical resection of a sacral tumor was performed in five patients. The sacral nerves were sacrificed bilaterally in three patients and unilaterally in two patients. Anorectal function was evaluated on the basis of symptoms and physiologic tests. Micturition function was evaluated based on symptoms, and intravesical pressures were measured by cystometry. Results. The two patients with unilateral sacral nerve loss did not experience subjective problems with defecation or micturition, although the residual volume of urine was increased after surgery. Two of the three patients with bilateral sacral nerve loss had no urge to defecate, were unable to differentiate between feces and flatus, and experienced no urgency. Fecal incontinence was uncommon because of firm feces. It was possible to control defecation using enemas on alternate days. The third patient underwent colostomy because the maximum resting pressure, which is controlled by the hypogastric nerves, was affected before surgery. Conclusion. Unilateral sacrifice of sacral nerves results in little bladder or anorectal dysfunction.