Open Ventral Hernia Repair: A Prospective Comparative Analysis of Onlay Versus Sublay Mesh Placement

Ventral hernia repair is among the most frequently performed general surgical procedures worldwide. Mesh-based repair has become the standard of care, but the optimal plane for mesh placement remains debated. This study compares outcomes of onlay and sublay techniques in open ventral hernia repair.

A prospective observational study enrolled 62 patients (31 per group) undergoing elective open ventral hernia repair at a tertiary care institute in India over 18 months. Postoperative wound complications (seroma, surgical site infection (SSI)), operative duration, hospital stay, and pain scores (Visual Analog Scale, postoperative days (POD) 1, 3, 5) were compared. Statistical analysis used the Mann-Whitney U test, the Chi-square/Fisher exact tests, and binary logistic regression (SPSS Statistics version 30 (IBM Corp., Armonk, NY, USA)).

Groups were comparable in age (onlay 51.3±14.2 vs sublay 51.7±11.0 years; p = 0.897), gender, body-mass index (BMI), and comorbidities. Seroma occurred significantly more often in the onlay group (32.3% vs 3.2%; p = 0.003). SSI rates were higher in onlay patients (25.8% vs 16.1%) but did not reach statistical significance (p = 0.349). Operative time was significantly shorter in the onlay group (94.4 vs 126.7 minutes; p<0.001). Onlay patients had less pain on POD 1 (p = 0.042). Median hospital stay was similar (9 vs 8 days; p = 0.155). No hematoma, mesh infection, or wound dehiscence occurred in either group. Subcutaneous fat thickness was an independent predictor of seroma (p = 0.026).

Both techniques are safe for open ventral hernia repair. Sublay mesh placement significantly reduces seroma formation and trends toward fewer SSIs, while onlay repair offers a shorter operative time and less immediate postoperative pain. Surgical decision-making should be individualized based on anatomical factors, comorbidities, and intraoperative findings.