Lumbar Mobility and Performance-Based Function: An Investigation in Older Adults with and without Chronic Low Back Pain.

Objective: To explore potential differences in lumbar mobility between older adults with and without chronic low back pain, and to determine if lumbar mobility contributes to physical performance in both groups. We hypothesized that older adults with pain would have greater lumbar mobility impairments than pain-free peers, and that lumbar mobility would be associated with performance in both groups, with stronger relationships among those with pain. Design: Matched case-control. Setting: Research laboratory. Patients: Community-dwelling older adults, aged 60-85 years, with (N = 54) and without (N = 54) chronic low back pain. Methods: Inclinometer-measured maximal angles of lumbar flexion, extension, and average side-bending, as well as time to complete performance measures, Repeated Chair Rise and Timed-Up-and-Go, were measured in both groups. Analysis of variance was used to explore the difference in lumbar mobility between groups. Adjusted linear regression was used to assess the independent relationship between lumbar mobility and physical function in both groups. Results: Those with pain had smaller angles of flexion ( P = 0.029) and extension ( P = 0.013). In the pain group, flexion explained 19% ( P = 0.001) and 8.9% ( P = 0.006) of the variance for time to complete the Repeated Chair Rise and Timed Up-and-Go tests, respectively. In the pain-free group, extension explained 12.7% ( P = 0.007) and 10.3% ( P = 0.008) of the variance for time to complete Repeated Chair Rise and Timed Up-and-Go tests, respectively. Conclusion: Older adults with chronic low back pain have more lumbar mobility impairments. Lumbar mobility may be a contributing factor to decreased performance in older adults. Flexion may be most important to performance in those with pain, while extension may be vital in those without pain.