# Is mesh pore size in polypropylene meshes associated with the outcome in Lichtenstein inguinal hernia repair: a registry-based analysis of 22,141 patients

## TL;DR

This study analyzed 22,141 patients to determine if mesh pore size affects outcomes in inguinal hernia repair, finding no significant differences in most outcomes.

## Contribution

The study provides clinical evidence on the association between mesh pore size and hernia repair outcomes using a large registry-based dataset.

## Key findings

- No association was found between mesh pore size and intraoperative or postoperative complications.
- Small-pore meshes showed a tendency for lower complication-related reoperation risk.
- Small-pore meshes were linked to reduced pain at rest and on exertion after one year.

## Abstract

Experimental data show that large-pored meshes reduce foreign body reaction, inflammation and scar bridging and thus improve mesh integration. However, clinical data on the effect of mesh porosity on the outcome of hernioplasty are limited. This study investigated the relation of pore size in polypropylene meshes to the outcome of Lichtenstein inguinal hernioplasty using data from the Herniamed registry.

This analysis of data from the Herniamed registry evaluated perioperative and 1-year follow-up outcomes in patients undergoing elective, primary, unilateral Lichtenstein inguinal hernia repair using polypropylene meshes. Patients operated with a non-polypropylene mesh or a polypropylene mesh with absorbable components were excluded. Polypropylene meshes with a pore size of 1.0 × 1.0 mm or less were defined as small-pored meshes, while a pore size of more than 1.0 × 1.0 mm was considered large-pored.

Unadjusted analyses and multivariable analyses were performed to investigate the relation of pore size of polypropylene meshes, patient and surgical characteristics to the outcome parameters.

Data from 22,141 patients were analyzed, of which 6853 (31%) were operated on with a small-pore polypropylene mesh and 15,288 (69%) with a large-pore polypropylene mesh. No association of mesh pore size with intraoperative, general or postoperative complications, recurrence rate or pain requiring treatment was found at 1-year follow-up. A lower risk of complication-related reoperation tended to be associated with small-pore size (p = 0.086). Furthermore, small-pore mesh repair was associated with a lower risk of pain at rest and pain on exertion at 1-year follow-up.

The present study could not demonstrate an advantage of large-pore polypropylene meshes for the outcome of Lichtenstein inguinal hernioplasty.