Effect of mesh plane on short-term surgical and functional outcomes in ventral hernia repair with associated rectus diastasis.

BACKGROUND: Optimal management of diastasis recti in patients undergoing ventral hernia repair remains uncertain, particularly regarding mesh plane selection. We compared wound morbidity and functional outcomes across mesh locations using a multi-institutional registry. METHODS: Retrospective cohort study using the Abdominal Core Health Quality Collaborative (ACHQC) registry (2015–2025). Eligible patients underwent elective ventral hernia repair with mesh and associated diastasis recti repair, with complete 30-day follow-up. The primary outcome was 30-day surgical site occurrence (SSO). Secondary outcomes included surgical site infection, readmission, reoperation, and patient-reported outcomes (HerQLes and PROMIS Pain Interference). RESULTS: Among 1,209 patients (mean age 55.0 ± 13.6 years, 49.7% female, mean BMI 31.4 ± 6.2 kg/m²), mesh location was retromuscular in 74.3%, intraperitoneal in 11.9%, preperitoneal in 9.3%, and onlay in 4.5%. The overall 30-day SSO rate was 7.8% and varied by mesh plane (p = 0.007): onlay 16.7%, retromuscular 8.4%, intraperitoneal 4.9%, and preperitoneal 2.7%. After multivariable adjustment, onlay placement had fivefold higher odds of SSO compared with retromuscular repair (OR 5.25, 95% CI 1.82–15.16, p = 0.002). Baseline HerQLes was the strongest predictor of postoperative HerQLes (β = 0.39; p < 0.001), but preperitoneal repair was associated with higher adjusted 30-day HerQLes compared with retromuscular repair. Baseline PROMIS predicted postoperative pain, while mesh location was not independently associated with 1-year pain. Onlay repair was performed in patients with lower BMI than retromuscular repair (25.9 vs. 32.0 kg/m²). CONCLUSIONS: Preperitoneal repair demonstrated the most favorable short-term wound profile, whereas onlay mesh placement was associated with higher early wound morbidity despite use in lower–body mass index patients. Baseline functional status was the primary determinant of postoperative quality of life and pain, highlighting the need for prospective studies to define optimal mesh positioning in diastasis recti repair.