Mechanical Parameters Influencing Recurrence in Ventral Midline Incisional Hernia Open Repair

Abstract Background Ventral midline incisional hernia (VMIH) is common and recurrence rates remain of concern after gold-standard open repairs. Personalized optimization and risk stratification are traditionally performed through preoperative considerations regarding patients’ general and medical status and occulting mechanical factors. Aims The aim of this retrospective observational cohort study is to identify mechanical parameters potentially influencing VMIH recurrence (VMIHR) after repair. Methods Data were derived from an institutional quality database. Patients who underwent VMIH open repair with retromuscular or preperitoneal non-absorbable mesh reinforcement, confirmed by an available preoperative CT scan for biomechanical measurements, between June 2012 – June 2020 in a single centre, were included. Exclusion criteria were non-open repairs, non-midline hernias, absence of preoperative scan, absence of mesh reinforcement, intraperitoneal/bridging mesh positions, biologic/biosynthetic mesh and use of component separation techniques. The main outcome was VMIHR, a symptomatic clinically confirmed recurrence re-operated in the same institution within 36 months maximum following primary open repair. Patients with/without recurrence were compared using standard analytic tools. Results Fourty-eight patients met the inclusion criteria of which 11 (23%) developed VMIHR. The following parameters were statistically significantly associated with VMIHR: smaller visceral fat surface (mean of 244.9 cm2 in the recurrence group vs 286.3 cm2 in non-recurrence group, p = 0.0295), smaller mesh length (17.2 cm vs 23 cm, p = 0.001), smaller total mesh surface (315.2 cm2 vs 550.1 cm2, p = 0.0095), coated meshes (p = 0.033), absorbable suture for mesh anchoring (p = 0.043) and a greater largest defect width/mesh width ratio (0.42 vs 0.29, p = 0.0146). Conclusions When focusing on mechanical parameters, non-modifiable and patient-related parameters seem to play a limited role. However, using uncoated meshes of larger dimensions (greater than/equal to 3.5x defect size) than suggested previously (defect size + 5cm) resulted in fewer recurrences. This may help to orientate further larger prospective trials.