Predictive factors for functional failure of ventral mesh rectopexy in the treatment of rectal prolapse and obstructed defecation

BACKGROUND: Ventral mesh rectopexy (VMR) is widely accepted for the treatment of rectal prolapse or obstructed defecation. However, despite good anatomical results, the improvement of functional symptoms (constipation or incontinence) cannot always be obtained and in some cases these symptoms may even worsen. The aim of the present study was to identify possible predictors of functional failure after VMR. METHODS: Data of all consecutive patients who had VMR for the treatment of rectal prolapse and/or obstructed defecation between January 2017 and December 2020 in three different pelvic floor surgical centres in Italy were analysed to identify possible predictors of functional failure, intended as persistence, worsening or new onset of constipation or faecal incontinence. Symptom severity was assessed pre- and postoperatively with the Wexner Constipation score and Obstructed Defecation Syndrome score. Quality of life was assessed, also before and after treatment, with the Patients Assessment of Constipation Quality of Life questionnaire, the Pelvic Floor Disability Index and the Pelvic Floor Impact Questionnaire. Faecal incontinence was evaluated with the Cleveland Clinic Incontinence Score. The functional outcomes before and after surgery were compared. RESULTS: Sixty-one patients were included (M:F ratio 3:60, median age 64 years [range 33-88 years]). Forty-two patients (68.9%) had obstructed defecation syndrome, 12(19.7%) had faecal incontinence and 7 patients (11.5%) had both. A statistically significant reduction between pre- and postoperative Obstructed Defecation Syndrome and Wexner scores was reported (p < 0.0001 in both cases). However, the postoperative presence of constipation occurred in 22 patients (36.1%) (this included 3 cases of new-onset constipation). The presence of redundant colon and the pre-existent constipation were associated with an increased risk of persistence of constipation postoperatively or new-onset constipation (p = 0.004 and p < 0.0001, respectively). The use of postoperative pelvic floor rehabilitation (p = 0.034) may reduce the risk of postoperative constipation. CONCLUSIONS: VMR is a safe and effective intervention for correcting the anatomical defect of rectal prolapse. The degree of prolapse, the presence of dolichocolon and pre-existing constipation are risk factors for the persistence or new onset of postoperative constipation. Postoperative rehabilitation treatment may reduce this risk.