Long-term retromuscular and intraperitoneal mesh size changes within a randomized controlled trial on incisional hernia repair, including a review of the literature

Purpose Ingrowth of fibroblasts in a polypropylene mesh may cause contraction and a later recurrence. We assessed mesh contraction in intraabdominal and retromuscular implantation after incisional hernia repair.

A cohort of patients within an RCT on laparoscopic (LHR) versus open hernia repair (OHR) had their mesh borders marked with metal clips. X-ray was performed on postoperative day 1 and after 1 year. Total length, width, and dislocation were measured. A tacker fixated large-pore polypropylene mesh was used in LHR, and a retromuscular small-pore heavy-weight mesh was sutured to the midline in OHR. Patient's pain was assessed before surgery and after 1 year.

For analysis 37/47 patients remained: 20 LHR and 17 OHR. Hernia defect area was median 41 cm² in LHR and 25 cm² in OHR (p < 0.140). Implanted mesh size was 300 cm² for LHR and 240 cm² for OHR (p < 0.341). After 1 year the mesh area decreased by 4.4% and 0.5% in LHR and OHR, respectively (p < 0.063). Longitudinal distance decreased by 2.8% in LHR and by 2.6% in OHR (p < 0.269). Transverse distance decreased by 1.6% in LHR but increased by 3.1% in OHR (p < 0.005). Dislocation was seen in four LHR and one OHR. Two recurrent and one port-site hernia were diagnosed after LHR. Measurements between observers were identical in 58% and consensus was made in the remainder. Pain was not correlated to mesh area change.

Mesh contraction after 1 year is not a clinical issue for an intraperitoneal large-pore mesh or a retromuscular small-pore mesh. It is not correlated to postoperative pain.