Enhancing Clinical Insights: New Radiographic Grading for Lumbar Facet Joint Degeneration, A Reliability Study

ABSTRACT Background Lumbar facet joint diseases can often lead to reduced work efficiency and increased medical costs. As a primary imaging tool in orthopedics, X‐rays offer numerous advantages. However, there is no consensus on the classification of lumbar facet joints based on X‐ray imaging. Methods This study was conducted for 356 patients between November 2017 and September 2023. A senior radiologist and a senior orthopedic surgeon discussed and established a grading system for lumbar facet joints based on both X‐ray and MRI findings. Two double‐blind attending spinal surgeons were asked to evaluate and grade the included cases. The intra‐rater reliability and inter‐rater reliability were evaluated by assessing the weighted kappa (κw) coefficient. Results The level of inter‐rater reliability of MRI for complete agreement was good for Doctor A (κw = 0.792) and Doctor B (κw = 0.869). The inter‐rater reliability coefficient for grading lumbar facet joint degeneration based on the radiograph was as follows: for Doctor A (κw = 0.702, session 1; κw = 0.847, session 2) and Doctor B (κw = 0.714, session 1; κw = 0.828, session 2). Moreover, the level of intra‐rater reliability based on X‐ray for complete agreement was excellent for Doctor A (κw = 0.843) and Doctor B (κw = 0.836). Conclusion We propose a new grading system for lumbar facet joint degeneration based on X‐rays, which serves as a supplement to the Weishaupt and Pathria classifications. This grading system aims to provide clinicians with a more comprehensive understanding of lumbar facet joint degeneration, allowing for the use of a broader range of diagnostic tools to evaluate facet joint degeneration from multiple perspectives. We believe that this grading system can be valuable in assessing potential anatomical changes related to the facet joint, thereby informing modifications to surgical techniques and procedural steps.