Purpose: The present study aimed to find reliability of magnetic resonance imaging (MRI) in patients with lumbar disk herniation.
Methods: In this cross-sectional study, 110 individuals aged 20-50 years with chronic low back pain (LBP) of more than 3 months were enrolled by nonprobability convenient sampling method. Only disk herniated patients of L4-L5 and L5-S1, diagnosed by physicians on the basis of MRI, were included in the study. Sagittal and axial MRI scans were taken and examined to rule out acute pathology. Two examiners interpreted the MRI results without knowing the results of clinical tests and questionnaires. Reliability at intra- and inter-level was done twice with the interval of 5 days. Reliabilities of findings such as affected disk level, extent of disk herniation, nerve root involvement, dehydration, and ligamentum flavum involvement were also assessed.
Results: Intra- and inter-test values for disk level were 0.87 and 0.80, for disk grade were 0.81 and 0.76, for lateral canal stenosis were 0.81 and 0.75, for dehydration were 0.81 and 0.72, for spondylolisthesis were 0.88 and 0.81, and for ligamentum flavum involvement were 0.79 and 0.75.
Conclusion: Repeatability of MRI results in patients with lumbar disk herniation at intra- and inter-level was good to excellent.