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Page 8 of 11 Fortelny. Mini-invasive Surg 2021;5:16 https://dx.doi.org/10.20517/2574-1225.2021.21

[57]
In the biomechanical study by Hollinsky et al. , the ultimate tensile strength and elasticity in association
with defect size of 1.5, 3 and 5 cm was assessed by the use of a lightweight mesh in comparison to a
heavyweight mesh. Regarding 1.5 cm of defect size no difference was seen, but in case of defect size 3 and 5
cm, the lightweight mesh flexed 3.16 +/- 0.4 mm and 10.4+/-2.5 mm significantly more in comparison to the
heavyweight mesh 0.34+/-0.2 mm and 3.97+/-0.7 mm (P < 0.001). This study is of main importance to
understand biomechanical relationships of mesh properties and defect size.

While meta-analyses to date have shown advantages for the use of lightweight meshes in laparo-endoscopic
[53]
inguinal hernia surgery , the inclusion of the TEP study by Ross et al. changed the recommendation not
[58]
to use lightweight meshes, especially in direct hernias, due to the increased risk of recurrence (RR 2.21;
95%CI: 1.14-4.31), especially in non-fixated mesh direct repairs (RR 7.27; 95%CI: 1.33-39.73) and/or large
[59]
hernia defects . No significant differences were determined in terms of pain and foreign body sensation.
Similar results were found in the meta-analysis of Hu et al. .
[60]
If you look at the EHS update guidelines from 2014 , you will find the recommendations for mesh fixation
[61]
in TEP if a heavyweight mesh is used: traumatic mesh fixation should be avoided except in large direct
inguinal hernias. For TAPP treatment, atraumatic mesh fixation without increased risk of recurrence within
one year was recommended.

Nowadays, in the nomenclature of mesh properties, light and heavy are obsolete; rather, effective porosity
and surface properties as well as elasticity are some of the defining properties of meshes. However, there is a
complex interplay between the polymer, textile structure, amount of material, porosity, processing of the
material, position and mechanical load on the mesh.

Despite some limitations of the available evidence, the HerniaSurge Group stated in the current guidelines
[6]
that mesh fixation is not required in almost all types of inguinal hernias in TEP repair. However, a strong
recommendation for mesh fixation was made for large medial inguinal hernias (MIII in the EHS
classification) for TAPP and TEP repair. If fixation is required, the HerniaSurge guidelines recommend an
atraumatic technique to reduce the risk of early postoperative pain.

In a Herniamed register study, 11,228 male patients with primary unilateral inguinal hernia underwent
[62]
TAPP technique and were followed up for 1 year. In this study published by Mayer et al. , mesh fixation
was performed in a total of 66.1% of the procedures. In the unadjusted analysis, there was no significant
difference in recurrence rate (0.88% with fixation vs. 1.1% without fixation; P = 0.259). In a multivariable
analysis of all potential influencing factors such as age, ASA, BMI, risk factors, defect size, mesh fixation,
location of the defect and mesh size, no factor was identified to influence the recurrence rate at 1-year
follow-up. However, for medial and combined defect localization in comparison to lateral localization, a
highly significant effect was detected (P < 0.001). Using mesh fixation and larger meshes, it was possible to
significantly reduce the recurrence rate for larger medial hernias in this series (P = 0.046). This registry
study clearly confirms the need of mesh fixation for MIII inguinal hernias, as recommended by the
HerniaSurge Guidelines, but also for combined inguinal hernias and impressively demonstrates the
advantage of using larger implants for recurrence prevention.

CONCLUSIONS
The central question of fixation or non-fixation of mesh in laparo-endoscopic inguinal hernia management
can only be viewed and answered on a multifactorial basis. According to the existing literature, it is
recommended that mesh fixation should be performed in case of medial as well as combined inguinal