Effects of mindfulness based cognitive therapy on disability, thickness of the lumbar multifidus muscle, fear avoidance beliefs and metacognitive beliefs in the subjects with non-specific low back pain

Introduction: Non-specific chronic low back pain is a large and costly musculoskeletal problem. It is affected by biological and psychological factors. There is preliminary evidence that mindfulness based cognitive therapy might be beneficial in chronic low back pain. The purpose of this study was to investigate the effect of Mindfulness based cognitive therapy in combination with stability exercise on thickness of the lumbar multifidus muscle, disability, fear avoidance beliefs and metacognitive beliefs in patients with non-specific chronic low back pain. Materials and Methods: This clinical trial study was performed on 40 non-specific chronic low back pain participants aged between 18-45 years. The participants were randomly assigned in two intervention and control groups. The scores of fear of pain, fear of movement, disability and metacognitive beliefs questionnaires were recorded. Correspondingly, the thickness of the lumbar multifidus muscle at the level of the L5 vertebra was measured by ultrasonography. The control group performed 8 sessions of stability exercises within 8 weeks (3 repetitions per week). The intervention group received stability exercises as mentioned above and mindfulness based cognitive therapy for 8 weeks (2 repetitions per week). At the end of the 8 weeks intervention, the variables immediately were assessed in both groups. Results: The results showed that there was no significant between-group difference on effect lumbar multifidus muscle thickness (P=0.76); but there were significant reduction in the avoidance of fear (fear of pain and fear of movement), disability, and meta-cognitive beliefs in the intervention group compared to the control group. (P= 0.000) Conclusion: Psychological factors associated with pain is one of the factors of low back pain continuation. The combination of mindfulness based cognitive therapy and stability exercises can help to further improvement of low back pain.