Page 39 - International guidelines for groin hernia management

Hernia

influenced by one study with a follow-up of only only included RCTs published prior to 2012. Since then,
12 months. A difference between LWM and HWM in two relevant RCTs have been published. A large 2015
Lichtenstein technique with regard to recurrence rate was study found no difference between LWM and HWM in the
not found in those meta-analyses. incidence of groin pain and foreign-body sensation. 425 A
TAPP surgery 2012 study concluded that, compared with a HWM, an
In TAPP there were no differences in perioperative or LWM provided no reduction in chronic groin pain and
chronic pain with LWM. However, postoperative recovery foreign-body sensation at 3-year follow-up. 391 There were
422
following TAPP seems to improve with LWMs. One no inter-group differences in recurrence rates.
study with a 3-year follow-up did find a significant dif-
2
ference between light (35 g/m ) and very-lightweight mesh Discussion
2
(15 g/m ) in TAPP repairs. A lower incidence of chronic
pain with the use of extra-light mesh was shown in this Regarding the many debates over different techniques and
study. 423 However, results of this study should be viewed different implants, the quality of the meta-analyses on
with caution since both meshes were LWM, and the weight mesh is crucial for good decision-making and guidance of
2
difference of 20 g/m only results in an overall difference surgical practice. Unfortunately, most of the studies
in weight of 0.218 g for a 10 cm 9 15 cm mesh. 390 This demonstrate a considerable heterogeneity of studies when
difference might be viewed as not clinically relevant. defining inclusion criteria, comparing techniques and
Another study showed that, despite higher perioperative material, or outcome. As the final result often depends on
analgesia requirements with HWM, the incidence of chronic the specific data of only some few studies, their inclusion
pain is similar to that seen with LWM. 424 Recurrence rates or exclusion may lead to conflicting conclusions. Also,
following TAPP repairs are the same with LWM and selection criteria remain quite unclear in some cases.
HWM. 422 In conclusion, with regard to chronic pain and For example, a 2012 publication did not take into account
recurrence rates until now a relevant difference between some prospective randomized trials. 405, 422, 424 and instead
LWM and HWM in TAPP technique has not been verified, case control studies were included. 426 A 2013 article
whereas clinical convalescence seems to improve with LWM. included the aforementioned studies, but also included a
TEP surgery surgeon’s-choice randomized study that was mistakenly
Todate,1650patientshavebeenstudied overperiods ranging considered to be computer generated. Also, the three meta-
from 3 to 12 months in prospective randomized trials. Some analyses from 2012 to 2013 did not properly account for
studies have found slight advantages concerning chronic differences in fixation techniques and combined modified
groin pain and other symptoms like foreign-body feeling or laparo-endoscopic techniques (TEP/TAPP) as well. Some
discomfort to LWM in TEP surgery. 393, 394, 396, 408 Higher of the included studies did not describe the mesh fixation
risk for recurrence rate when using LWM was not observed. technique used or compared different fixation
methods. 396, 406, 408, 424, 427
Systematic reviews and meta-analysis Given the bias in all studies HerniaSurge can only weakly
suggest to use an LWM when considering postoperative
Three meta-analyses reviewing various aspects of TEP or pain as outcome.
TAPP laparo-endoscopic surgery have been pub-
lished. 415–417 Review results varied slightly with regard to Mesh–foreign-body reaction
endpoints, recurrence rates, postoperative pain, chronic
Introduction
pain, return-to-work and seroma formation. One of the
meta-analyses concluded that short- and long-term results Mesh implantation induces a foreign-body reaction in the
following surgery with either LWM or HWM are compa- recipient’s tissues leading to an encapsulation of the
416
rable across all relevant endpoints. A second concluded polymer fibers by a granuloma of inflammatory and fibrotic
that there were probably higher recurrence rates with cells. Since inflammation is related to scar formation, any
LWM, but less groin pain and foreign-body sensation. 417 chronic inflammatory process results in permanent cell
The third also concluded that LWM was associated with turnover which in turn leads to scar accumulation and
less groin pain and foreign-body sensation, but found no constantly increasing collagen deposition. Considering the
increase in recurrence rate. 415 All called for more studies functional consequences of excessive scarring, the matter
on the topic; two suggested that studies with longer follow- of chronic inflammation at mesh/tissue interfaces is
up times be performed. The three meta-analyses differed important since it may represent a permanent risk for
broadly due to study selection for inclusion, heterogeneity patients. A related issue is whether the foreign-body
of the selected studies, and quality assessment of the reaction attenuates over time. Both issues impact risk
included studies. Additionally, the three meta-analyses assessment for mesh implants.

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