Adhesions after laparoscopic inguinal hernia repair. A comparison of extra versus intra peritoneal placement of a polypropylene mesh in an animal model.

Prosthetic mesh for laparoscopic inguinal hernia repair has become popular but the method of its placement is controversial. Mesh placed within the peritoneum may cause adhesion formation and further complications. The aim of this study was to examine the laparoscopic placement of a mesh, comparing intraperitoneal vs extraperitoneal insertion. In a porcine model (n = 15) a polypropylene mesh was placed laparoscopically over the anterior abdominal wall. On the left side the mesh was stapled on the parietal peritoneum. On the right side the peritoneum was incised, an extraperitoneal space was dissected, the mesh was inserted, and the peritoneum was closed over it. The animals were maintained for 2 weeks. At postmortem there were adhesions in two of those placed extraperitoneally and five of those placed intraperitoneally (P = 0.19, Fisher's exact test). The adhesions comprised fibrous peritoneal bands to loops of small intestine. Both methods of laparoscopic mesh placement were associated with a small but significant incidence of adhesion formation.