Post-operative clinical, manometric, and defecographic findings in patients undergoing unsuccessful STARR operation for obstructed defecation.

Aim: To evaluate the reason for failure of STARR (stapled transanal rectal resection) operation for obstructed defecation.
Methods: A retrospective study (June 2012-December 2017) was performed using a prospectively maintained database of patients who underwent STARR operation for ODS (obstructed defecation syndrome), complaining of persisting or de novo occurrence of pelvic floor dysfunctions. Postoperative St Mark's and ODS scores were evaluated. A VAS was used to score pelvic pain. Patients' satisfaction was estimated administering the CPGAS (clinical patient grading assessment scale) questionnaire. Objective evaluation was performed by dynamic proctography and anorectal manometry.
Results: Ninety patients (83.3% females) operated for ODS using STARR technique were evaluated. Median ODS score was 19 while 20 patients (22%) reported de novo fecal urgency and 4 patients a worsening of their preoperative fecal incontinence. Dynamic proctography performed in 54/90 patients showed a significant (> 3.0 cm) rectocele in 19 patients, recto-rectal intussusception in 10 patients incomplete emptying in 24 patients. When compared with internal normal standards, anorectal manometry showed decreased rectal compliance and maximum tolerable volume in patients with urgency. Nine patients reported a persistent postoperative pelvic pain (median VAS score 6).
Conclusion: Failure of STARR to treat ODS, documented by persisting ODS symptoms, fecal urgency, or chronic pelvic pain, is often justified by the persistence or de novo onset of alteration of the anorectal anatomy at defecation. This occurs in about half of the patients, but in 40% of the cases who complained of incomplete emptying or incontinence, anatomical abnormalities were not recognized.