Simplified Universal Grading of Lumbar Spine MRI Degenerative Findings: Inter-reader agreement of non-radiologist spine experts.

OBJECTIVE 1) To describe a simplified multidisciplinary grading system for the most clinically relevant lumbar spine degenerative changes. 2) To measure the inter-reader variability of non-radiologist spine experts in interpreting a consecutive series of lumbar spine MRI utilizing the classification. METHODS A multidisciplinary and collaborative standardized grading of spinal stenosis, foraminal stenosis, lateral recess stenosis, and facet arthropathy was developed. Our institution's PACS was searched for 50 consecutive patients who underwent non-contrast MRI lumbar spine for chronic back pain, radiculopathy, or symptoms of spinal stenosis. Three fellowship-trained spine subspecialists from neurosurgery, orthopedic surgery, and physiatry interpreted the 50 exams utilizing the classification at the L4-L5 and L5-S1 levels. Inter-reader agreement was assessed with Cohen's kappa coefficient. RESULTS For spinal stenosis, the readers demonstrated substantial agreement (k = 0.702). For foraminal stenosis and facet arthropathy the three readers demonstrated moderate agreement (k = 0.544, and 0.557, respectively). For lateral recess stenosis, there was fair agreement (k = 0.323). CONCLUSIONS A simplified universal grading system of lumbar spine MRI degenerative findings is newly described. Utilization of this multidisciplinary grading system in the assessment of clinically relevant degenerative changes revealed moderate to substantial agreement among non-radiologist spine physicians. This standardized grading system could serve as a foundation for interdisciplinary communication.