A study to improve identification of the retroperitoneal course of iliohypogastric, ilioinguinal, femorocutaneous and genitofemoral nerves during laparoscopic triple neurectomy

MEsh FIxation in Laparoendsocopic Repair of Large M3 inguinal hernias: multicenter, double-blinded, randomized controlled trial-study protocol for a MEFI Trial

BACKGROUND

International guidelines of groin hernia treatment strongly recommend to fixate the mesh in large M3 medial defects during TAPP/TEP procedures. The main purpose of fixation is to decrease the recurrence rate which is alarmingly high in case of those defects. In 2022, a team consisting of hernia surgeons and scientists from universities of technology conducted an experimental study with the use of 3D groin model to verify the hypothesis that fixation is not necessary in above cases. Experiment showed that rigid and anatomically shaped meshes are able to maintain its position in the groin without fixation. Similar conclusions were recently published in Swedish database registry analysis. To confirm above results, we decided to conduct a multicenter randomized controlled trial.

METHODS

Main objective of MEFI Trial is to verify the hypothesis that non-fixation of spatial, standard polypropylene meshes is non-inferior to fixation of flat, polypropylene lightweight meshes in M3 hernias by laparoendoscopic approach. Eleven large surgery centers in Poland having proficiency in laparoendoscopic groin hernia repairs were recruited for this study. Recurrence in 12-month follow-up was set as a primary endpoint. Pain sensation (Visual Analog Scale) and incidence of other complications (hematoma, seroma, SSI) were also noted. Based on the statistical analysis, minimal sample size in both arms was established at 83-102. The first arm (control) consists of patients undergoing a repair with the use of a flat, macroporous mesh with fixation using histoacryl glue. In the second arm, patients will be operated with the use of anatomically shaped, standard-weight mesh without fixation. Study will be double-blinded (patient/surgeon). After the dissection of preperitoneal space, surgeon will open a sealed envelope and find out which technique he will have to perform. Follow-up will be performed by Study Secretary (also blinded to the method used) via phone call 3 and 12 months after surgery.

DISCUSSION

Based on experimental study and recent registry analysis, we believe that the recurrence rate in both groups would be on the same level, giving hernia societies a strong argument for amending the guidelines.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05678465. Registered on 10 January 2023.

Is mesh fixation necessary in laparoendoscopic techniques for M3 inguinal defects? An experimental study

BACKGROUND

Although international guidelines recommend not fixing the mesh in almost all cases of laparoendoscopic repairs, in case of large direct hernias (M3) mesh fixation is recommended to reduce recurrence risk. Despite lack of high-quality evidence, the recommendation was upgraded to strong by expert panel. The authors conducted a research experiment to verify the hypothesis that it is possible to preserve the mesh in the operating field in large direct hernias (M3) without the need to use fixing materials.

METHOD

The authors conducted an experiment with scientists from Universities of Technology in a model that reflects the conditions in the groin area. By simulating conditions of the highest possible intra-abdominal pressure, they examined the mesh behavior within the groin and its ability to dislocate under the forces generated by this pressure. The experiment involved six spatial implants and one flat macroporous mesh.

RESULTS

Heavyweight spatial meshes and lightweight spatial-individualized meshes showed no tendency to dislocate or move directly to the orifice, which was considered a rapid hernia recurrence. Lightweight meshes, both spatial and flat, underwent significant migration and shifting toward the hernial orifices.

CONCLUSION

Based on the results, we believe that mesh fixation is not the only alternative to preventing recurrence in complex defects. Similar effects can be achieved using a larger, more rigid, and anatomically fitted implant. The type of implant (rather than its fixation) seems to be a key factor from the point of view of mechanics and biophysics. Clinical trials confirming the results in vivo will allow to supplement or amend the guidelines for the treatment of large inguinal hernias.

Anatomical Variations of the Iliohypogastric Nerve: A Systematic Review of the Literature

Several anatomical variations of the iliohypogastric nerve branches have been observed in earlier studies. Knowledge of these variations is useful for the improvement of peripheral nerve blocks and avoidance of iatrogenic nerve injuries during surgeries. The purpose of this study was to perform a systematic review of the literature about the anatomical topography and variations of the iliohypogastric nerve. An extensive search on PubMed, Scopus, and Web of Science electronic databases was conducted by the first author in November 2021, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Anatomical or cadaveric studies about the origin, the course, and the distribution of the iliohypogastric nerve were included in this review. Thirty cadaveric studies were included for qualitative analysis. Several anatomical variations of the iliohypogastric nerve were depicted including its general properties, its origin, its branching patterns, its course, its relation to anatomical landmarks, and its termination. Among them, the absence of the iliohypogastric nerve ranged from 0 to 34%, its origin from L1 ranged from 62.5 to 96.5%, and its isolated emergence from psoas major ranged from 47 to 94.5%. Numerous anatomical variations of the iliohypogastric nerve exist but are not commonly cited in classic anatomical textbooks. The branches of the iliohypogastric nerve may be damaged during spinal anesthesia and surgical procedures in the lower abdominal region. Therefore, a better understanding of the regional anatomy and its variations is of vital importance for the prevention of iliohypogastric nerve injuries.