Dynamic response of spinal implants investigation
Spine is an important component of the human skeleton, which can support the upper body through transmitting compressive and shear forces to the lower body in daily life. However, many people suffer chronic low back pain which limits their activity and lower their overall quality of life. It has been accepted that instances of spinal instability may be a pivotal factor in the etiology of low back injuries. Many researchers have studied the biomechanical response of the spine and spinal implants in order to get more information to reduce lower back injuries and develop strategies to treat spine related diseases.
Recent research has demonstrated the unique dynamic properties of natural spinal tissues. On the other hand, biomechanical evidence points towards a critical role of damping in the function of implants for reconstruction of the spinal column. However, present implant evaluation methods are typically aimed at evaluating the quasi-static mechanical properties of the device. There are still no efficient test methods and standards for evaluating the dynamic response of biomaterials for spinal implants.
In this project, we will develop novel testing methods for the evaluation of the non-linear dynamic response of silicon nitride, including impact and frequency-dependent resonance as well as direction dependent hardening or softening effects. Advanced imaging (micro CT) methods will be used for descriptive measures of as-produced internal microarchitecture for correlation to mechanical response. Furthermore, the changes to base mechanical properties and overall structural damping resulting from gel infiltration and/or tissue ingrowth into macro-porous implants will also be evaluated.