Graft-related complications and biaxial tensiometry following experimental vaginal implantation of flat mesh of variable dimensions

Abstract

Objective: To compare the occurrence of graft-related complications (GRCs) and biomechanical properties of meshes implanted vaginally and abdominally.

Design: In vivo animal experiment.

Setting: Centre for Surgical Technologies, Medical Faculty, KU Leuven, Belgium.

Population: Twenty adult parous Texel ewes.

Methods: Sheep were implanted with Gynemesh M, a 28-g/m² polypropylene mesh reinforced with polyglecaprone fibres, under general anaesthesia. Dissection into the rectovaginal septum was performed to accommodate a flat 50 × 50 mm (n = 10) or 35 × 35 mm (n = 10) mesh, which was sutured to the underlying tissues. A 50 × 50 mm mesh was laid over a primarily sutured, full-thickness, 40-mm longitudinal abdominal wall incision. Sacrifice was at 60 days (n = 10) or 90 days (n = 5).

Main outcome measures: The occurrence of exposure, the degree of contraction and examination of the biomechanical properties of explants with a minimum radius of 32 mm via biaxial tensiometry.

Results: Insertion of a 50 × 50 mm mesh led to exposures in 30% (3/10) of cases, and the average contraction rate was 52 ± 14%. In the 35 × 35 mm implants, there were no exposures, and the contraction rate was 25 ± 26.3%. Vaginal explants with no GRCs and of sufficient size had biomechanical properties that were comparable with those of abdominal explants.

Conclusion: Vaginal mesh insertion is associated with GRCs, such as exposure and contraction. Although other factors probably play a role, this study illustrates that mesh size may also induce these complications. In a vaginal surgery model, clinically occurring GRCs can be reproduced. In addition, biomechanics of uncomplicated vaginal explants are comparable with those measured on abdominal explants.