BIOLAP: biological versus synthetic mesh in laparo-endoscopic inguinal hernia repair: study protocol for a randomized, multicenter, self-controlled clinical trial.

Background: Inguinal hernia repair is one of the most common surgical operations globally; more than 20 million groin herniae are repaired annually worldwide. Recurrence after an inguinal hernia operation is a considerable clinical problem. Another remaining problem after hernia surgery is the occurrence of chronic pain. Up to now, the use of synthetic meshes is the standard procedure, but there is increasing evidence that biological meshes could be advantageous concerning the occurrence of chronic pain due to different postoperative remodeling, without the disadvantages of a life-long implant. We hypothesize that the use of a biological mesh reduces postoperative pain without being inferior in terms of recurrence rate compared with a synthetic mesh.

Methods/design: The trial compares possible the advantages of biological matrices to synthetic meshes in laparo-endoscopic inguinal hernia repair. Four hundred and ninety-six patients with primary bilateral inguinal herniae in 20 German hernia centers will be enrolled. Biological mesh is used for one of the bilateral herniae, the other side will be operated on with a synthetic mesh. Randomization will preset which side is repaired with which material and trial participants will not be informed about the location of each mesh type. The primary endpoints will be intensity of postoperative local pain and the incidence of recurrent hernia after 2 years.

Discussion: There is no reasonably sized trial that assesses the use of biological meshes in laparo-endoscopic inguinal hernia repair. Our self-controlled trial design allows a direct comparison of the two meshes with very few confounding factors as well as minimizing the exclusion criteria. As we compare CE-certified medical devices in their designated indication the medical risk is not different compared to routine clinical care. Due to the common nature of bilateral inguinal hernia, a high recruitment rate is achievable. Because guidelines for hernia repair have stressed the need for reliable data on the already frequent use of biological meshes, we can expect our trial to have a direct implication on hernia-repair standards.

Trial Registration: German Clinical Trials Register, ID: DRKS00010178 . Registered on 16.June.2016. BIOLAP underwent full external peer review as part of the funding process with the German Research Foundation.