Evaluation of a fully absorbable poly-4-hydroxybutyrate/absorbable barrier composite mesh in a porcine model of ventral hernia repair

Background

The objective of this study was to evaluate the mechanical and histological properties of a fully absorbable poly-4-hydroxybutyrate/absorbable barrier composite mesh (Phasix? ST) compared to partially absorbable (Ventralight? ST), fully absorbable (Phasix?), and biologically derived (Strattice?) meshes in a porcine model of ventral hernia repair.

Methods

Bilateral abdominal surgical defects were created in twenty-four Yucatan pigs, repaired with intraperitoneal (Phasix? ST, Ventralight? ST) or retromuscular (Phasix?, Strattice?) mesh, and evaluated at 12 and 24 weeks (n = 6 mesh/group/time point).

Results

Prior to implantation, Strattice? demonstrated significantly higher (p < 0.001) strength (636.6 ± 192.1 N) compared to Ventralight? ST (324.3 ± 37.1 N), Phasix? ST (206.9 ± 11.3 N), and Phasix? (200.6 ± 25.2 N). At 12 and 24 weeks, mesh/repair strength was significantly greater than NAW (p < 0.01 in all cases), and no significant changes in strength were observed for any meshes between 12 and 24 weeks (p > 0.05). Phasix? mesh/repair strength was significantly greater than Strattice? (p < 0.001) at 12 and 24 weeks, and Ventralight? ST mesh/repair strength was significantly greater than Phasix? ST mesh (p < 0.05) at 24 weeks. At 12 and 24 weeks, Phasix? ST and Ventralight? ST were associated with mild inflammation and minimal–mild fibrosis/neovascularization, with no significant differences between groups. At both time points, Phasix? was associated with minimal–mild inflammation/fibrosis and mild neovascularization. Strattice? was associated with minimal inflammation/fibrosis, with minimal neovascularization at 12 weeks, which increased to mild by 24 weeks. Strattice? exhibited significantly less neovascularization than Phasix? at 12 weeks and significantly greater inflammation at 24 weeks due to remodeling.

Conclusions

Phasix? ST demonstrated mechanical and histological properties comparable to partially absorbable (Ventralight? ST) and fully resorbable (Phasix?) meshes at 12 and 24 weeks in this model. Data also suggest that fully absorbable meshes with longer-term resorption profiles may provide improved mechanical and histological properties compared to biologically derived scaffolds.