Summary
Objectives: Our objectives were to 1) Biomechanically compare two laparoscopic repair techniques;
an automated suturing device and a stapling device to conventional open suturing,
and 2) Evaluate a model for canine diaphragmatic tissue by comparisons to similar
constructs in fresh diaphragms. We hypothesized that automated suturing is biomechanically
superior to laparoscopic stapling in dogs, and that neoprene defect repair is an acceptable
model for experimental cadaveric diaphragm herniorrhaphy.
Materials and methods: Samples of diaphragm pars costalis were prepared with defects mimicking radial muscular
tears. Defects were repaired using conventional open suturing, laparoscopic automated
suturing, and laparoscopic stapling techniques. Similar defects were created in 6.35
mm thick single-sided neoprene. Samples were biomechanically tested across a biaxial
loading machine. Site and mode of failure were noted for all samples.
Results: In both the diaphragm muscle and neoprene, the laparoscopic stapling technique was
significantly weaker. The neoprene model showed a similar failure load as the diaphragm
in both laparoscopic techniques, and a similar stiffness in an open-sutured and stapled
diaphragm compared to the neoprene samples. Site and mode of failure in neoprene were
similar to cadaveric diaphragmatic tissue, but the overall median load-to-failure
was higher for the neoprene.
Conclusion: The strength of laparoscopically repaired simulated diaphragmatic hernias was higher
with an automated suture technique than with a stapling technique. Neoprene defect
repair is an acceptable model of canine diaphragmatic herniorrhaphy for biomechanical
testing.
Keywords
Laparoscopy - herniorrhaphy - Minimally invasive