SUCCESSFUL OVERLAPPING ANAL-SPHINCTER REPAIR - RELATIONSHIP TO PATIENT AGE, NEUROPATHY, AND COLOSTOMY FORMATION

BACKGROUND: Fecal incontinence from single anal sphincter defects are surgically remedial and commonly the result of obstetric injuries. Ove rlapping anal sphincter repair has previously been associated in small series with good results in 69 to 97 percent of patients. OBJECTIVES: The aims of this study were to assess the results of overlapping anal sphincter repair in one institution and to assess the effects of age, presence of a neuropathy, and addition of a temporary colostomy on th e success of surgery. METHODS: A study of 57 overlapping anal sphincte r repairs in 56 (54 females) patients at the Royal Prince Alfred Hospi tal during a six-year period was performed. All patients were investig ated preoperatively with endoanal ultrasound and concentric needle ele ctromyography. Patients have been assessed prospectively since 1994 wi th a questionnaire, including a four-point Likert scale of continence level, the St. Mark's incontinence scoring system (range, 0-13), the P escatori incontinence scoring system (range, 0-6), and patient assessm ent of success or failure of the overlapping anal sphincter repair. A colostomy was selectively formed in conjunction with an overlapping an al sphincter repair in 21 patients (8 preoperatively, 13 simultaneousl y), and 18 patients had a concomitant neuropathy (3 unilateral, 15 bil ateral). RESULTS: After a median follow-up of 18 months, median contin ence scores overall had improved from St. Mark's incontinence scoring 13 to 3 (P < 0.0001) and Pescatori incontinence scoring 6 to 2 (P < 0. 0001). Forty-nine of 57 (86 percent) repairs have been successful, and 8 are considered to be failures. Twenty-one of 27 (78 percent) repair s in patients younger than 40 years of age were successful, as were 28 of 30 (93 percent) repairs in patients older than 40 years of age (P = 0.10). Four of 18 (22 percent) repairs associated with a neuropathy failed compared with 4 of 39 (10 percent) without a neuropathy (P = 0. 21). Improved or normal continence was achieved in 17 of 21 (81 percen t) patients with a stoma and overlapping anal sphincter repair and in 32 of 36 (89 percent) patients with an overlapping anal sphincter repa ir alone (P = 0.32). The presence of a stoma did not improve the rate of wound healing by primary intention (62 percent for stoma vs. 64 per cent for overlapping anal sphincter repair alone; P = 0.55). CONCLUSIO NS: Single anal sphincter defects can be successfully treated with an overlapping anal sphincter repair. There is no Improvement in primary healing with selective stoma formation. Age of the patient and presenc e of a neuropathy should not detract from proceeding with overlapping anal sphincter repair when singular anal sphincter defects are detecte d on endoanal ultrasound in muscle that is still active.