Page 43 - International guidelines for groin hernia management

Hernia

National registry data analyses usually show a nearly Of note, mesh polymers themselves do not shrink, but
linear increase in reoperation rate, reflecting a permanent the textile itself shortens, pulled together by the contracting
risk with an almost constant incidence over time. 78, 513, 514 scar. 366 Thick and stiff filaments in a rigid textile implant
It is therefore, reasonable and logical to think that lifetime resist shrinkage more than large-pore meshes and offer
risk of complications will be increased for younger flexibility adapted to surrounding tissues. 381
patients, though there are no data confirming this. A long Mesh shrinkage varies markedly. For plugs, a volume
implantation period should be considered a mesh-related reduction due to shrinkage of up to 90% has been reported
515
complication risk factor when considering the risk/benefit with the formation of a so-called meshoma. It is rea-
ratio of mesh repair. sonable that mesh area shrinkage of greater than 50%
increases postoperative risks and should be avoided if
Mesh shrinkage
possible by minimizing surgical trauma and/or foreign-
Introduction body reaction. 388, 515–529
Shrinkage of the mesh—caused mainly by collagen short- Studies of MRI-visible large-pore PVDF mesh report an
ening—results in physiological wound contraction. This up to 20% reduction in mesh surface area indicating a
phenomenon, in turn, is related to scar tissue amount, shortening across length and width of about 10%. 530 These
influenced by surgery-induced local tissue trauma and studies confirm the results of a 2011 trial performed with
patient-specific responses to tissue injury. digital computed radiographs and metal clips at a Licht-
enstein mesh border. 518
Key question However, today these changes are small in relation to
the accuracy of the CT/MRI measurements, and thus need
KQ10.j Does mesh shrinkage occur, and if so, to what to be confirmed by further studies.
extent?

Evidence in literature
It is known that certain patients develop enhanced scar Chapter 11
formation and/or marked wound contraction, whereas
others do not. It is also known that textile meshes induce a
chronic foreign-body reaction with local inflammation and Mesh fixation
fibrosis (see KQ10e). In the case of small-pore meshes this
reaction can bridge the entire inter-filament distance. 366, 382 R. H. Fortelny, D. L. Sanders and A. Montgomery
Thus, small-pore meshes develop increased shrinkage in
the area of surgical trauma. Mesh infection, with its Introduction
resultant inflammation and increased fibrosis, exacerbates Synthetic mesh fixation in both open and laparo-endo-
this process and results in even more shrinkage. scopic hernia repair involves a consideration of the strength
of fixation versus the risk of trauma to local tissues and

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