Prophylactic mesh reinforcement for midline incisional hernia prevention: systematic review and updated meta-analysis of randomized controlled trials

Background: Incisional hernia (IH) is a common complication after abdominal surgery. Prevention of IH is matter of intense research. Prophylactic mesh reinforcement (PMR) has been shown to be promising in the minimization of IH risk after elective midline laparotomy. Methods: Systematic review and meta-analysis of randomized controlled trials (RCTs) comparing PMR vs. primary suture closure (PSC). Risk ratio (RR) and standardized mean difference (MD) were used as pooled effect size measures whereas 95% confidence intervals (95%CI) were used to assess relative inference. Results: Fourteen RCTs (2332 patients) were included. Overall, 1280 (54.9%) underwent PMR while 1052 (45.1%) PSC. Postoperative follow-up ranged from 12 to 67 months. The incidence of IH was reduced for PMR vs. PSC (13.4% vs. 27.5%). The estimated pooled IH RR for PMR vs. PSC is 0.38 (95% CI 0.24–0.58; p < 0.001). Stratified subgroup analysis according to mesh location shows a risk reduction for intraperitoneal (RR = 0.65; 95% CI 0.48–0.89), preperitoneal (RR = 0.18; 95% CI 0.04–0.81), retromuscular (RR = 0.47; 95% CI 0.24–0.92) and onlay (RR = 0.24; 95% CI 0.12–0.51) compared to PSC. The seroma RR was higher for PMR (RR = 2.05; p = 0.0008). No differences were found for hematoma (RR = 1.49; p = 0.34), surgical site infection (SSI) (RR = 1.17; p = 0.38), operative time (OT) (MD = 0.27; p = 0.413), and hospital length of stay (HLOS) (MD = -0.03; p = 0.237). Conclusions: PMR seems effective in reducing the risk of IH after elective midline laparotomy compared to PSC in the medium-term follow-up. While the risk of postoperative seroma appears higher for PMR, hematoma, SSI, HLOS and OT seems comparable.