Long-Term Outcomes of Surgical vs. Conservative Management of Chronic Anal Fissures

Background. Chronic anal fissure is highly prevalent, and the decision to undertake pharmacological sphincter relaxation (SR) versus lateral internal sphincterotomy (LIS) remains a matter of debate. While the short-term healing rates are well established, the long-term outcomes greater than two years and the relationship with continence are less predictable. Aim. To compare long-term healing, recurrence, pain, continence, quality of life, and patient satisfaction following surgical versus conservative management of adult patients with chronic anal fissure, and to elucidate predictors of long-term treatment failure. Methods. Using a cross-sectional design, a tertiary colorectal unit identified all adult patients treated for chronic anal fissure from 01/01/25 until 31/3/26. Patients were followed up with history, clinical examination, a visual analogue scale for pain, the Wexner score for anal incontinence, the Euro Qol 5D 5L (EQ-5D-5L), and an interview by a colorectal surgeon unfamiliar with the index intervention. Statistical analysis employed the independent samples t-test, Mann-Whitney U test, Chi-square or Fisher's exact test, and binary logistic regression. Statistical significance was set at p < 0.05. Results. The mean (standard deviation) age of patients was 38.6 (11.2) years and 34.2 (7.9) months from intervention. Both groups were comparable at baseline. Long-term healing rates were greater with LIS at 71/78 (91.0%) vs. 52/81 (64.2%) SR patients ( 2.30-13.91, 7.558.66 OR, p < 0.001), and there was less recurrence at 7.7% versus 38.3% ( 2.80-203.08, 20.80OR, p < 0.001) and crossover or re-intervention rates at 5.1% versus 27.2% (p < 0.001). Pain at follow-up was less after LIS at VAS 1.2 (1.1) vs. 2.6 (1.8) ( 2.31, 6.946.94, p < 0.001), while EQ-5D-5L scores were better at 0.89 (0.09) vs. 0.81 (0.13) ( 2.94, 5.414.21, p < 0.001). The rate of any continence disturbance was higher after LIS at 11.5% (9/78) versus 2.5% (2/81) (p = 0.030); however, these were limited to slight soiling or flatus, and there was no incontinence to solid stool. Multivariate logistic regression revealed conservative management (1.09-5.11, 2.48-11.79, p < 0.001), persistent constipation (1.32-6.55, 2.94, p = 0.009), and duration of symptoms > 1 year (1.09-5.11, 2.36, p = 0.011) independently predicted long-term failure. Conclusion. Although sphincterotomy provided significantly greater and more durable resolution of symptoms than medical therapy at a mean follow-up of 38 months, the residual risk of a minor continence disturbance was low. Conservative management remains appropriate; however, those with chronicity or untreated constipation should be made aware that definitive intervention is unavoidable.