Evaluation of dynamic creep properties of surgical mesh prostheses--uniaxial fatigue.

In this study, we examine the dynamic creep behavior of four commonly used commercial hernia meshes (Prolene, Ultrapro, Vypro, and Vypro II). The meshes, differing from each other with respect to composition and architecture, were tested under uniaxial tension at simulated physiological loads and environmental conditions. The changes in percentage strain elongation, secant modulus, and cyclic energy dissipation over 100,000 cycles were compared. All of the meshes evaluated were found to be overengineered compared to physiological-loading criteria and displayed good load-carrying performance. When all meshes were tested at 37 degrees C in physiological saline, they survived 100,000 cycles of sinusoidal loading without fracture, except Ultrapro. Interestingly, irrespective of the differences in structure and composition, all meshes underwent strain-hardening and permanent plastic deformation. Scanning electron micrographs of the meshes showed evidence of yarn thinning, decrimping, and fracture. The results of this study suggest that strain-hardening of the meshes under dynamic loading could be a possible cause for complications related to abdominal mobility during long-term implantations.