Magnetic Resonance Imaging Evaluation Of The Degeneration Of The Multifidus And Erector Spinae Muscles In Patients With Chronic Mechanical Low Back Pain, Patients With Herniated Disc, And Healthy Individuals

Abstract Background: The determination of appropriate treatment methods for patients with chronic low back pain may be possible with the determination of the cause of the pain. Therefore, it can be considered that identification of the morphological changes of the paraspinal muscles in patients with chronic low back pain and comparison with control subjects is necessary to explain the relationship of these with pain. The aim of this study was to examine degeneration in the lumbar musculus multifidus (LMF) and lumbar musculus erector spinae (LES) in patients with mechanical chronic low back pain, patients with chronic low back pain with lumbar herniated disc and no radiculopathy, and healthy individuals, and through comparison of the results according to gender, pain and lumbar segments, to examine the relationship with low back pain. Material and Method: The study included 35 patients with mechanical low back pain, 38 patients with lumbar herniated disc and no radiculopathy, and a control group of 36 healthy subjects. The patients were evaluated in respect of LMF and LES cross-sectional area (CSA), total CSA (TCSA=LMF+LES), fat infiltration and asymmetry on axial magnetic resonance imaging (MRI) slices at the L3-S1 level. Results: The mean CSA values of the right and left LMF and LES showed significant differences between the groups (p<0.001, p=0.002, p=0.002, p=0.010, respectively). The mean values obtained in the healthy control group were lower than those of the other two groups. Fat infiltrations showed a difference between the right-left LMF and left LES groups (p=0.007, p<0.001, p=0.026, respectively). Asymmetry was not observed between the CSA and TCSA of the right and left sides. No significant relationship was determined between the duration of low back pain and the CSA and TCSA values and fat infiltration. Conclusıon: A relationship was determined between fat infiltration in LMF and mechanical low back pain and LDH. The low CSA and TCSA values in the healthy control group suggest that it is due to a pseudohyertrophy mechanism. This shows that when evaluating muscle mass, rather than CSA and TCSA, the functional cross-sectional area (FCSA) or muscle atrophy associated with fat infiltration should be measured.