Design of a screw-plate system to minimize loosening in sternal fixation

The use of screw-plate fixation devices after open heart sternotomy surgeries are becoming more prevalent with studies showing the device´s mechanical superiority. However, there is no current device that is capable of supplying both a compressive and locking force needed to optimally fixate the plate to the bone. This can lead to screw loosening and wobbling within the plate, potentially compromising the integrity of the overall system. The goal of the design is to create an “anti-wobble” screw-plate sternal fixation device capable of reducing sternal displacement post sternotomy plate fixation more efficiently than current market devices. The device will supply “rigid sternal fixation” in the stabilization of two full hemi-sterna, and will allow for minimal screw loosening and back out. The device contains both a locking and compressive mechanism, enhancing the bone-plate interface. Validation testing on the device is currently being completed using an Instron Electroplus E-1000 uniaxial testing device to conduct low loading cyclic testing on human cadaveric sterna.