Incisional hernia repair in a high-fidelity silicone model for open retro-muscular mesh implantation with preparation of the fatty triangle: validation and educational impact study



Incisional hernia repair requires detailed anatomic knowledge. Regarding median subxiphoidal hernias, the proper preparation of the fatty triangle is challenging. To foster proficiency-based training, a cost-efficient model for open median retromuscular mesh repair resembling the human body was developed, including the main anatomical structures related to the procedure. The aim is to create and validate a high-fidelity model on open retromuscular mesh repair suitable for "training before doing".

Materials and methods

Different types of fabrics for imitation of connective tissue and 2-component silicones were used to construct the incisional hernia model. Sample size for validation of the model was determined by a triangular testing approach. Operations from six beginners and six experts were assessed by three blinded-raters. Reliability and construct-validity were evaluated on a behaviorally anchored rating scale (highest score: 4) for the criteria: “instrument use”, “tissue handling”, “near misses and errors”, and “end-product quality”.


The model authentically mimicked an open median retromuscular mesh repair. Participants considered the procedure realistic. Reliability was excellent, ranging from 0.811 to 0.974 for “end-product quality”, and “tissue handling“ respectively. Construct-validity was confirmed with experts significantly outperforming beginners in the “use of instruments” (Mbeg. = 2.33, Mexp. = 3.94, p < 0.001), “tissue handling” (Mbeg. = 2.11, Mexp. = 3.72, p < 0.001), “near misses and errors” (Mbeg. = 2.67, Mexp. = 3.67, p < 0.001), and “end-product quality” (Mbeg. = 2.78, Mexp. = 3.72, p < 0.001). Criterion-validity revealed a paradox effect: beginners performed significantly better than experts (p < 0.05) when preparing the fatty triangle.


The model covers all relevant aspects involved in median-open retromuscular incisional hernia mesh repair. Performance differences between beginners and experts confirm construct-validity and thereby realism of the model. It enables to efficiently improve and practice technical skills of the demanding surgery.

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Author information




All the authors contributed to the final preparation of this article, including approval of the final version of the manuscript. CTZ and UF equally contributed to this study. CTZ and UAD developed the surgical simulator based on the work of SM. CTZ, SK and UAD conceived and designed the study. CTZ, JB and UAD wrote the final study protocol and together with SM and AW drafted the manuscript. CTZ and UAD implemented and ran the study, and collected the results. CTZ and JB analyzed the data and performed the statistical analyzes. UF, SAG, SO and FP developed the online platform.

Corresponding author

Correspondence to U. A. Dietz.

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Conflict of interest

The authors disclose that there was no conflict of interest. The study was funded by the Medical Faculty Wuerzburg, Germany (Grant no. 620–2015) and third-party funds of working group of the Division of Hernia Repair and Abdominal Wall Reconstruction of the University Hospital Wuerzburg.

Ethical approval

The review and ethics board of the Medical Faculty of the University of Wuerzburg was consulted and it did not consider an approval necessary, since the study protocol was not deemed to represent biomedical or epidemiological research (Protocol No. 20161013 02).

Human and animal rights

Sensible identificatory data were treated according to the data protection policy of the University of Wuerzburg.

Informed consent

Consent to video-recording of the procedure without personal identificatory captures was obtained at the beginning of the study from each participant.

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Zipper, C.T., Friedrich, U., Backhaus, J. et al. Incisional hernia repair in a high-fidelity silicone model for open retro-muscular mesh implantation with preparation of the fatty triangle: validation and educational impact study. Hernia 24, 1307–1315 (2020).

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  • Simulation
  • Validation
  • Incisional hernia repair
  • Retromuscular mesh repair
  • Fatty triangle
  • Surgical model