Document Type : RESEARCH PAPER
Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences
Physical Therapy Department, School of Rehabilitation Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
Neuromuscular Rehabilitation Research Center, Department of Physiotherapy, Semnan University of Medical Sciences, Semnan, Iran
Objective: The objective of this study was to investigate the relationships between lumbar spine-hip dis-coordination during sit-to-stand (STD) and stand-to-sit (SIT) and pain and functional disability in patients with chronic non-specific low back pain (CNLBP).
Method: A cross-sectional observational study was conducted in a biomechanics laboratory of physical therapy department located at the School of Rehabilitation Sciences, Iran University of Medical Sciences (Tehran, Iran). Sixteen CNLBP patients (men 9, female 7) aged between 18 and 40 years (mean age 31.48 years) were selected according to our eligibility criteria. Ten reflective markers were placed on the spinous processes of T12 and S2, posterior and anterior superior iliac spines, greater trochanters, and lateral epicondyles. The participants were asked to perform STD and SIT tasks at a preferred speed without using their hands. Relative phase angle was used as an indicator coordination and was defined as the inverse tangent of angular velocity/angular displacement. The relative phase angle between lumbar spine and hip joints was quantified by subtracting the phase angle of hip joint from the lumbar spine joint. The ratios of the total movements of the lumbar spine to those of the left hip and to the right hip were also calculated in the sagittal plane. Finally, Pearson correlation coefficients (r) were used to assess the relationship between variables.
Results: The results of this study showed large to very large direct relationships between kinematic parameters and pain and functional disability in CNLBP participants during STD and SIT with r values ranging from 0.57 (P value = 0.021) to 0.85 (P value < 0.001) and 0.54 (P value = 0.053) to 0.82 (P value < 0.001), respectively.
Conclusions: From the results of this study, it can be concluded that pain and functional disability play a major role in lumber spine-hip dis-coordination and altered lumbar spine to hip movement ratio in CNLBP patients during STD and SIT. In clinical practice, clinicians should improve lumber spine-hip dis-coordination in patients with CNLBP since there is a linear relationship between kinematic parameters and pain and functional disability in patients with CNLBP.