In Reply

Our correspondents focus on two important aspects—chronic pain and mesh technology—which require additional explanatory comments.

1. The study reported by Neumayer used meshes with a vertical extension of 8.1 cm and 8.5 cm; the smaller meshes were associated with a significantly raised rate for recurrence, as was pointed out in the correspondence submitted in response to the primary publication (1). This shows the technical deficiencies of this study. The Finnish study is based on data from Finland’s patient insurance scheme and compensation claims brought by patients, not on the measured incidence of severe complications. The evaluation of the Danish hernia registry shows a lower rate of pain and infections for laparoscopic/endoscopic techniques. The higher complication rate after this technique stems from—as the authors explained—a higher incidence of complications, which are not specified in the registry. Consequently, no conclusions can be drawn about their nature and severity. The evidence from numerous clinical studies—that laparoscopic/endoscopic techniques for hernia repair are associated with lower rates of chronic pain—therefore remains untouched. A US-based registry analysis with high-quality data was cited in our article in the context of the rate of severe complications; this study did not show any advantage for open techniques.

2. The categorical recommendation of mesh-based repairs is formulated in the cited guidelines and supported by highest-level evidence. Suture-based approaches do not offer any advantage with regard to chronic pain or other complications, as was shown by a meta-analysis cited in the article (2). A systematic review with meta-analysis studied the adverse effect on retropubic prostatectomy after pre-peritoneal mesh-plasty (3). A reduced lymph node yield was found, as was a prolonged period of catheterization without any other drawbacks. The comparison of inguinal hernia repair and prolapse surgery in women is inappropriate: in one setting, an extended mesh is placed without tension, in the other, a mesh strip is placed under partial conditions of tension. The question of biocompatibility remains unanswered as even the definition is not consistent and obviously unresolved (4). It is only the definition, however, that a system of tests can be based on. An implant registry to evaluate long term results is urgently required, but this has to be based on data of satisfactory quality in order to enable reliable conclusions.

In sum, I wish to emphasize that the article’s conclusions are based in the available evidence and the guidelines resulting from this evidence. The literature cited in the correspondence was familiar but was not considered where it was not up to date and where higher-level evidence was available.