Background: Multifidus muscle (MF) in the back of the vertebral column plays an important role in spinal stability. MF morphology and fatty infiltration can be influenced by factors affecting low back pain (LBP) and evaluated using MRI, CT and US, however MRI provides a higher resolution and allows for better detection of soft tissues.
Objective: We proposed a new method to assess the degree of MF degeneration.
Methods: The multifidus score was calculated by summation of degree of MF degeneration, with minimum score of 0 and maximum of 6. In cases of disproportion affection of MF on each side, we chose the higher degree of MF affection. Score of 6 means that MF degeneration is graded 2 in either side. We mentioned the influence of other vertebral degenerative pathologies including facet arthropathies, neural canal stenosis and Modic end plate changes. We defined disc pathology as disc bulge, herniation. The main factors affecting MF degeneration are age, body mass index (BMI), duration of compliant in years, presence of sciatica and VAS visual analogue scale (VAS) score.
Results: VAS scores were statistically significantly correlated with degree of MF degeneration, with p value < 0.001. The degree of MF degeneration was significantly correlated with number of disc pathologies.
Conclusion: Our study concluded a significant relation between MF degeneration and each of VAS and duration of pain, although this relation was not related to the measurement of proportionate changes between each side and different degrees of MF degeneration.