Background and objectives: Segmental instability of lumbar vertebrae is one of the complications of patients with non-specific low back pain, accounting for 30-40% of them. The aim of this study was to determine the effect of the thoracic and lumbar stability exercises on pain and disability of women with non-specific chronic low back pain. Methods and Materials: For this randomized clinical trial, 20 women with non-specific chronic low back pain were selected using the convenient sampling method. Patients were randomly assigned into two equal groups: thoracic stability exercises and lumbar stability exercises. The thoracic stability exercises and lumbar stability exercises were selected based on McGill's principles. Before and after intervention, the pain severity was measured through Visual Analog Scale (VAS) and the disability was measured through Oswestry Disability Index (ODI). The exercises of both groups were performed 6 weeks and three times per week. Paired t-test and independent t-test were used to analyze the data. Results: The mean pain severity decreased from 6.00 ± 0.81 to 2.00 ± 1.49 (p = 0.00) in the thoracic stability exercise group, and it decreased from 5.30 ± 0.82 to 2.30 ± 1.56 in the lumbar stability exercises group (p = 0.00). The mean disability severity decreased from 42.00 ± 9.6 to 26.40 ± 7.64 in the thoracic stability exercise group (P = 0.00) and it decreased from 47.00 ± 5.75 to 28.60 ± 4.52 in the lumbar stability exercise group (P = 0.00). There was no significant difference between two groups in terms of severity of pain and severity of disability (P>0.05). Reduction in pain severity in the thoracic stability exercises group was higher than lumbar stability exercises group, while the reduction in functional disability was more in lumbar stability exercises group compared to that of thoracic stability exercises. Conclusion: Thoracic stability exercises and lumbar stability exercises reduced pain and disability in women with non-specific chronic back pain.
