Tensile strength and adhesion formation of mesh fixation systems used in laparoscopic incisional hernia repair

Mesh tearoff from the tissue is the most common reason for hernia recurrence after hernia surgery involving the use of a synthetic mesh. Various fixation systems were critically compared in terms of their retention strength and the formation of adhesions. In a prospective study with 25 Sprague-Dawley rats, two pieces of Parietex composite meshes measuring 2 x 3 cm were fixed intraperitoneally in a paramedian location. The randomized mesh fixation groups included transfascial fixed suture, ProTack, AbsorbaTack, and I-Clip. Of the 25 rats, 12 were killed and analyzed 1 week after implantation, with the remaining 13 rats killed and analyzed after 2 months. Adhesions observed at the time of mesh removal were measured according to an adhesion scoring system, and the fixation strengths of the individual fixation systems were tested. Additionally, the foreign body reaction to the mesh and fixation systems was measured as well as their potential degradation. After 1 week, the retention strength of transfascial fixed suture was significantly higher (8.7 N/cm(2)) than that of ProTack (5.6 N/cm(2)) or AbsorbaTack (5.7 N/cm(2)). After 2 months, the retention strength had increased to 13.2 N/cm(2) in the transfascial fixed suture group, which was significantly higher than in the ProTack (9.7 N/cm(2)) or AbsorbaTack (8.7 N/cm(2)) groups. In contrast, the mesh could be fixed with the I-Clip only in 56% of the cases, and then achieved rather poor retention strength. Adhesion was significantly greater in the ProTack group than in any of the other groups (p < 0.001). At 2 months, scanning electron microscopy showed only marginal degradation of the absorbable elements. Suture fixation led to satisfactory attachment of the prosthesis. Additional widespread anchorage of the mesh was achieved with ProTack or AbsorbaTack. The feasibility and retention strength of the I-Clip were poor.