Design and development of a biomechanical apparatus to test the integrity of the Luque orthopaedic internal bone-plate fixation system.

This paper describes the design and construction of a biomechanical model that will determine the pull-out strengths and fatigue failure of internal fixation devices used at the lumbosacral junction. Fusions at this junction have the highest failure rate. It is suggested that devices that successfully fix this vertebral unit will be effective at other levels of the spine. A model that tests any device designed for use at the lumbosacral junction will therefore provide a uniform measure of the effectiveness of different kinds of instrumentation at the L5-S1 vertebral unit. It will also provide predictive values for fixation systems at other spinal levels. A real-time data-acquisition system was also designed and used to define and determine the failure of the Luque orthopaedic bone-plate fixation device.