British Journal of Surgery 1998, 85, 1433–1438 Third-degree obstetric perineal tear: long-term clinical and functional results after primary repair A. C. POEN*†, R. J. F. FELT-BERSMA*†, R. L. M. STRIJERS‡, G. A. DEKKER§, M. A. CUESTA† and S. G. M. MEUWISSEN* Departments of *Gastroenterology, †Surgery, ‡Clinical Neurophysiology and §Obstetrics and Gynaecology, University Hospital ‘Vrije Universiteit’, Amsterdam, The Netherlands Correspondence to: Mrs R. J. F. Felt-Bersma, Department of Gastroenterology, University Hospital ‘Vrije Universiteit’, PO Box 7057, 1007 MB, Amsterdam, The Netherlands Background This study was designed to investigate the long-term clinical and anorectal functional results after primary repair of a third-degree obstetrical perineal rupture. Methods One hundred and fifty-six consecutive women who had a primary repair of a third-degree perineal rupture were sent a questionnaire and asked to undergo anorectal function testing (anal manometry, anorectal sensitivity, anal endosonography and pudendal nerve terminal motor latency (PNTML)) Results Some 117 women (75 per cent) responded. Anal incontinence was present in 47 women (40 per cent); however, in most cases only mild symptoms were present. In 40 women additional anorectal function tests were performed and compared with findings in normal controls. Mean(s.d.) maximum squeeze pressure (31(15) versus 63(17) mmHg, P  0·001) was decreased and first sensation to filling of the rectum (88(47) versus 66(33) ml, P = 0·03) and anal mucosal electrosensitivity (4·7(1·7) versus 2·5(0·8) mA, P = 0·003) were increased compared with values in normal controls. In 35 women (88 per cent) a sphincter defect was found with anal endosonography. Factors related to anal incontinence were the presence of a combined anal sphincter defect (relative risk (RR) 1·7 (95 per cent confidence interval (c.i.) 1·1–2·8)) or subsequent vaginal delivery (RR 1·6 (95 per cent c.i. 1·1–2·5)). Conclusion Anal incontinence prevails in 40 per cent of women 5 years after primary repair of a third-degree perineal rupture. The presence of a combined sphincter defect or subsequent vaginal delivery increase the risk of anal incontinence. Anal incontinence occurs in approximately 2·2 per cent of the general Western population, especially in women 1 . Many women with anal incontinence have a history of one or more difficult vaginal deliveries. After a third-degree perineal tear, which involves rupture of the anal sphincters and occurs in about 0·4–5 per cent of vaginal deliveries 2–7 , anal incontinence rates from 19–58 per cent within several months after the rupture 2,4,8–12 to 7–42 per cent after several years 8,9,11 have been reported. These complaints can have serious consequences for the social, psychological and sexual life of those affected. The exact cause of anal incontinence after third-degree perineal tear is not clear. Both sphincter rupture and pudendal nerve damage are considered pathophysiological factors 4,13–15 . Anal endosonography, which provides clear images of the anal sphincters, is advocated in the assessment of anal incontinence 16,17 , as well as other anorectal function tests, and might help insight to be gained into the pathophysiology of anal incontinence after third-degree perineal tear. The aim of this study was to investigate long-term clinical and anorectal functional results after primary repair of a third-degree obstetrical perineal rupture. Patients and methods Between 1985 and 1994, 156 women (approximately 1·8 per cent of all vaginal deliveries 5 ) with a mean age of 31 (range 18–43) years underwent primary repair of a third-degree obstetric perineal tear (anal sphincter tear) in the authors’ hospital. A complete third-degree obstetric anal sphincter tear was defined as a rupture of the perineum with total separation of the anal sphincters, with or without a breach of the anal epithelium 3,4 . When some fibres of the anal sphincter remained intact, the third-degree tear was defined as incomplete 3 . All tears were confirmed and sutured by a staff gynaecologist. The torn ends of the anal sphincters, which were retracted, were identified and approximated with interrupted or ‘figure of 8’ sutures of polyglactin 18 . The vaginal mucosa, perineal muscles and skin were then repaired as in routine episiotomy. Postoperative complications included wound infection in four patients and anovaginal fistula in two. Nineteen women were lost to follow- up. The remaining 137 women were sent a questionnaire 1–10 years after the anal sphincter tear (mean follow-up 4·7 years), containing questions about anal incontinence, urinary incontinence, vaginal flatus and dyspareunia. The severity of anal incontinence was assessed by a 100-mm visual analogue scale (VAS), the descriptions at each end being ‘no distress’ and ‘distress couldn’t be worse’. In addition, all women who were sent a questionnaire were asked to undergo anorectal function tests. The study was approved by the medical ethics committee. Anorectal function tests Anal endosonography. Anal endosonography was performed with a Diagnostic Ultrasound System (type 3535; Br¨ uel and Kjër, Naerum, Denmark) with a 7-MHz rotating endoprobe (type 1850, focal range 2–4·5 cm) covered by a water-filled hard sonolucent cone (diameter 1·7 cm), producing a 360° view of the anal canal. Serial images of the anal sphincters were obtained both transvaginally 19 and transanally. Mean internal and external Paper accepted 17 April 1998 © 1998 Blackwell Science Ltd 1433