Burst inflation test for measuring biomechanical properties of rat abdominal walls

Purpose Evaluation of potential grafts to improve upon current strategies for abdominal wall (AW) repair in small animal models typically involves mechanical testing using methods that currently are inadequate to assess physiologically relevant parameters. This study introduces burst inflation testing as a more relevant assessment of the mechanical integrity of the AW compared to traditional tensile testing. Methods AWs were excised from 14 healthy adult Fischer 344 rats and tested using either a custom burst inflation device or an Instron tensile testing system. Modulus outcomes from both testing methods were compared. Results Mechanical analyses of native AW using burst and tensile testing methods resulted in similar average tissue moduli, but with the burst test, there was significantly less variability among specimens. Conclusions The burst test had greater repeatability compared to tensile testing and has the ability to test repaired AWs without compromising the integrity of the repair site, making it a useful tool for assessing graft repairs.