Novel pedicle screw designs for spine surgery

Pedicle screw is an important part to connect spinal implant and bone that has already been used for more than 70 years.  However, screw loosening is still a problem that causes implant failure, especially for osteoporotic patients whose bones are relatively weaker. Several studies show that the geometry of screws will influence the pull-out strength, which is a parameter to indicate the stability of screws.

In the BMS group, we aim to optimize the pedicle screw to reduce the loosening rate.

Firstly, human bone and screw are modelled to simulate the pull-out process. Compared to pull-out experiments, numerical simulation is less time consuming and repeatable. Furthermore, numerical simulation can predict mechanical behavior rather than test and measure them, which is important for optimization.

Secondly, the numerical models are utilized to optimize the stability of the pedicle screw by changing the geometry. The novel designs are outputted and manufactured with the 3D printing technique. Finally, the novel pedicle screw designs will be tested in vitro and in vivo to validate the mechanical and biological performance.

If you have questions about this project please contact Yijun Zhou