Correlation between grading of fat infiltration in multifidus muscle and degree of facet joint arthropathy in degenerative spondylolisthesis patients based on lumbosacral MRI: a cross-sectional study

Background: Degenerative spondylolisthesis is a disorder caused by displacement of one vertebral body by one above or below it due to degenerative changes. Possible contributing causes of degenerative spondylolisthesis are facet joint osteoarthritis and inadequate muscle stabilization. The facet joint and multifidus muscle are innervated by the medial branch of the dorsal ramus of the segmental nerve. This study aims to investigate the relationship between grading of multifidus muscle fat infiltration and degree of facet joint arthropathy in patients with degenerative spondylolisthesis based on lumbosacral MRI. Methods: This research employs a cross-sectional observational design, utilizing secondary data from the Picture Archiving and Communication System (PACS) and medical records. The aim is to investigate the relationship between the grading of multifidus muscle fat infiltration and the severity of facet joint arthropathy in patients with degenerative spondylolisthesis, based on non- weight-bearing lumbosacral MRI. The study includes all data stored in the PACS at our center from January 2022 until the required sample size was reached. Results: This study analyzed 100 non-weight-bearing lumbosacral MRI samples of patients with degenerative spondylolisthesis. The distribution of samples based on lumbar multifidus muscle fat infiltration revealed that grade 2 had the highest prevalence at 33%. Similarly, the distribution based on facet joint arthropathy showed the highest occurrence at grade 2, or moderate, at 45%. Significant relationships were found between gender and age with lumbar multifidus muscle fat infiltration (p<0.05), and between gender and spinal level with facet joint arthropathy (p<0.05). Additionally, there is a strong positive correlation (r=0.64; p<0.05) between the grading of the multifidus muscle and the degree of facet joint arthropathy in these patients. Conclusion: There is a strong positive and significant correlation between grading multifidus muscle and degree of facet joint arthropathy in patients with degenerative spondylolisthesis.