Page 38 - International guidelines for groin hernia management

Hernia

meshes of different weight in Lichtenstein, TEP or TAPP all their possible confounders almost is impossible in
surgery. These studies will be discussed in KQ10c. clinical studies!

Discussion Key question
Though some of the clinical (RCT)studies have presented
significantly different results between different treatment KQ10.c Are outcomes influenced by mesh weight? Do
groups, many could not, and ended up in non-significant lightweight meshes have benefits in open or laparoscopic
differences. This is often interpreted as equivalence, which IH repair?
is not justified.
Complications in mesh-based hernia surgery sometimes Introduction
are mesh-related, but often result from failures during the
surgical procedure, impaired wound healing, and/or by There is an ongoing debate about the mesh type best suited
material-induced inflammation and scarring with subse- for IH repair. So-called LWMs are supposedly associated
quent functional damage. A mix of risk factors for com- with lower discomfort and less pain. However, they are
plications is always at play. These limitations and feared to result in higher recurrence rates than so-called
confounders mean that statistically significant differences HWMs. 393, 415–417 The analysis presented below—with
are achieved only in some studies focussing just on the special attention to data from meta-analyses—is intended
comparison of materials. Whereas a significantly improved to clarify the issue.
outcome in a comparative clinical study can serve as an

argument for a specific device, as obviously the impact Evidence in literature
exceeds the risk of an alpha-error; however, the non-find- Open surgery
ing of a significant difference may not serve as an argument Some prospective randomized studies using Lichtenstein
due to the low statistical power in most studies. Cohorts of technique show advantages for LWM during the first
less than 1000 patients usually are related with an unac- postoperative weeks and months (\ 3 months) with regard
ceptable risk for a beta-error (which means that the finding to pain. 404, 412, 418, 419 Two of those studies evaluated long-
is not representing the truth). The absence of a significant term chronic pain (60 months follow-up). Those studies do
finding therefore usually results from the limitations of the not find differences between LWM and HWM. Meta-
sample size rather than can be regarded as a real fact. analyses find fewer instances of chronic pain for LWM in
Consecutively, to prove the similarity of two materials with the long term. 415, 419–421 Those analyses are strongly

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