Abstract
This study uses in vitro experiments and validated finite element models (FEM) to analyze the effect of posterior fixation, alone or associated with expandable device (ED) and/or cement. 3-dimensional FEMs of intact, fractured and instrumented spine were built and compared with experimental load-displacement curves. FEM ranges of motion were within the experimental corridors. Stresses appeared sensitive to both implant configuration and fracture severity with a stress reduction up to 84%. The FEM highlighted that for a same instrumental strategy, different biomechanical performances were observed according to fracture severity. When bone continuity is altered, both ED and cement may be needed.
Acknowledgment
The authors are grateful to Stryker (VEXIM) for their financial support in this research project.
Disclosure statement
Financial support was received from Stryker to support material costs related to the evaluation of the implants and their modeling. Authors do not have any personal business or financial benefit from the support of this research.