Close lateral internal sphincterotomy versus open lateral internal sphincterotomy for chronic anal fissure: a systematic review and meta-analysis.

Background: Lateral internal sphincterotomy (LIS) has been the gold standard for treating chronic anal fissure (CAF) that persists despite other measures. The authors aim to evaluate the effects of the close method (CLIS) of performing LIS as compared to the open method (OLIS).

Methods: Databases were searched for relevant studies and results were screened to identify eligible articles, and all concerned outcomes were pooled as odd ratio (OR) or mean difference (MD) with 95% CI in the meta-analysis models using RevMan 5.4.

Results: Pooled data from 16 trials with 1,711 patients with idiopathic CAF showed that the CLIS has significant lower risk of delayed fissure healing [OR: 0.28, 95% CI (0.10, 0.77), = 0.01], duration of hospital stay [MD: -0.82 with 95% CI (-1.07, -0.57), < 0.00001] and postoperative visual analogue pain score (VAPS) at 24 h [MD: -0.30 with 95% CI (-0.39, -0.21), < 0.00001]. Also, the risk of overall complications [OR: 0.33 with 95% CI (0.19, 0.55), < 0.0001], incontinence [OR: 0.28 with 95% CI (0.20, 0.38), < 0.00001], and postoperative pain [OR: 0.56 with 95% CI (0.35, 0.91), = 0.02] was significantly lower with CLIS.

Conclusion: CLIS is a safer option than OLIS for treating anal fissure. The risk of delayed fissure healing, incontinence, post-op pain and overall complication was significantly lower. However, the risk of surgical site infection, postoperative bleeding and recurrence did not differ. Future research with more prolonged follow-up is necessary to document recurrence reliably.