Kono-S anastomosis for Crohn's disease: a systemic review, meta-analysis, and meta-regression

The Kono-S anastomosis was introduced in 2011 as an alternative anastomosis in Crohn's disease (CD) surgery. Since then, prevailing evidence of the favorable results of the Kono-S anastomosis has been published from around the world. We conducted this study to analyze the effectiveness of the Kono-S anastomosis, by searching Medline, Embase, CNKI, and google scholar. Binominal data were analyzed after Freeman-Tukey double-arcsine transformation. Comparative data were analyzed using the Mantel-Haenszel model for dichotomous outcomes and the mean difference for continuous outcomes. We identified 676 patients who underwent surgery with a Kono-S anastomosis. Surgical recurrence was pooled at an average of 0% (CI: 0.00-0.01) and a reduced mean Rutgeerts score of 1.375 (CI: 0.727-2.023) after Kono-S anastomosis. Endoscopic recurrence after sensitivity analysis was 5% (CI: 0.00-0.15). Complications were rare, with a 3% incidence of ileus (CI: 0.01-0.05), a 4% incidence of small bowel obstruction (CI: 0.01-0.10), a 1% incidence of an anastomotic leak incidence (CI: 0.00-0.03), and a 10% incidence of postoperative infection (CI: 0.03-0.20). Evidence from this meta-analysis favors the Kono-S anastomosis for CD patients, especially for ileocolic anastomosis. Thus, clinicians should consider the applicability of Kono-S anastomosis in respective institutions.