Correlation between posterior paraspinal muscle atrophy and lumbar intervertebral disc degeneration in patients with chronic low back pain

Background Although enormous studies have been devoted to solving the problem of intervertebral disc degeneration/herniation, little attention is paid to the effect of paraspinal muscles on it. We aimed to investigate the correlation between paraspinal muscle atrophy and lumbar disc degeneration to recognize paraspinal muscle atrophy and its importance to the spine. Patients and methods A total of 107 patients were enrolled in the study (65 females, 42 males; age 50.87 ± 15.391 years old). Cross-sectional area, functional cross-sectional area, and fatty infiltration of the posterior paraspinal muscles were measured at the level of L4/5, and the degree of facet joint degeneration was evaluated at the levels of L3/4, L4/5, and L5/S1 by MRI. After controlling the confounding factors by multiple linear regression, the correlations among paraspinal muscle atrophy, disc degeneration, and facet joint degeneration were analyzed. Meanwhile, Pearson/Spearson rank analysis was used to analyze the correlation between clinical symptoms (VAS and ODI) and paraspinal muscle atrophy. Results There was a strong correlation between paraspinal muscle atrophy and disc degeneration after controlling the confounding factors ( p < 0.05, R > 0.5). There was a weak correlation between paraspinal muscle atrophy and facet joint degeneration ( p < 0.05, R < 0.5). There was a significant correlation between facet joint degeneration and intervertebral disc degeneration ( p < 0.05, R > 0.7). The fatty infiltration of paraspinal muscle was weakly correlated with ODI ( p < 0.05, R < 0.3), but VAS was not. Conclusions The degree of paraspinal muscle atrophy increased with lumbar disc degeneration and facet joint degeneration and fatty infiltration of multifidus was more susceptible to weight.