Abstract
Introduction
Over the last two decades, different techniques to stabilize the spine have been developed. The gold standard in spinal stabilization today is the pedicle screw. However, different techniques like different types of facet fixation devices are available. Based on different principles of facet fixation, a new implant is available, the so called “Facet Wedge.” The purpose of this study is to evaluate the primary stability of this new approach for facet fixation in comparison with established posterior fixation techniques such as pedicle screws and translaminar screws with and without anterior cage interposition.
Materials and Methods
In a two-arm biomechanical study using a robot-based spine tester, 24 monosegmental fresh frozen nonosteoporotic human motion segments (L2–L3 and L4–L5) were tested. Facet Wedge stand-alone and in combination with an anterior fusion cage was compared with pedicle screws and translaminar screws.
Results
All tested techniques could stabilize an intact motion segment effectively. In the used setup, Facet Wedge was comparable to pedicle screws for lateral bending, extension, and flexion and slightly superior for axial rotation. Facet Wedge showed a superior kinematic capacity compared with translaminar screws.
Conclusion
Facet Wedge offers a novel posterior approach in achieving primary stability in lumbar spinal fixation. In the used model, Facet Wedge has a comparable primary stability to pedicle screws and potential advantages over translaminar screws.