Mesh shrinkage depends on mesh properties and anchoring device: an experimental long-term study in sheep.

Harsløf, S; Zinther, N; Harsløf, T; Danielsen, C; Wara, P; Friis-Andersen, H

PURPOSE The choice of mesh and anchoring device in laparoscopic ventral hernia repair is controversial. Clinically important long-term properties of mesh and anchoring device such as mesh shrinkage have been sparsely investigated. Furthermore, the effect of various anchoring devices on mesh properties has never been examined. METHODS In 20 sheep, using laparoscopy, we inserted three PhysiomeshTM (large pore, lightweight) and three VentralightTMST (small pore, mediumweight), anchored with ProTackTM, SecurestrapTM or GlubranTM, respectively. After 6 and 12 months, 10 sheep at each time-point, we euthanized the animals, harvested the meshes with fascia, and measured the exact size and area of the mesh, expressing mesh shrinkage as a percentage of the initial area. RESULTS The shrinkage of PhysiomeshTM was 35.7 %, 23.8 % and 17.7 % when anchored with ProtackTM, GlubranTM or SecurestrapTM, respectively. Shrinkage with ProtackTM was significantly higher than with either GlubranTM or SecurestrapTM, respectively (p<0.01 and p<0.01). The shrinkage of VentralightTMST was 19.3 %, 22.2 % and 19.6 % when anchored with ProtackTM, GlubranTM and SecurestrapTM, respectively (p>0.05 for all pairwise comparisons). Overall shrinkage of PhysiomeshTM anchored with ProtackTM was significantly higher for all comparisons (p<0.01). CONCLUSION Our results suggest that mesh shrinkage in sheep takes place within 6 months after implantation. A significant interaction between mesh and type of anchoring indicates that shrinkage may depend on both mesh properties and anchoring device. The results of the current study imply that the combined effect of mesh and anchoring device should be evaluated in future studies.