Examination of the lumbar movement pattern during a clinical test and a functional activity test in people with and without low back pain.

Background: It is assumed that the lumbar movement pattern observed during a clinical test is representative of the movement pattern used during a functional activity. Very little is known about how the lumbar movement pattern during a clinical test is associated with the lumbar movement pattern during a functional activity and how the lumbar movement pattern is associated with functional limitation. Objective: The purpose was to examine the lumbar movement pattern during a clinical test and a functional activity test in people with and people without low back pain (LBP), and the relationship of lumbar motion to LBP-related functional limitation. Design: Observational study. Participants: 16 back-healthy adults and 32 people with chronic LBP. Methods: Participants performed a standardized clinical test of forward bending and a functional activity test of picking up an object. Main Outcome Measurements: Maximal lumbar excursion and lumbar excursion at 0% to 50% and 50% to 100% of movement time were examined. Results: Significant associations were present between the two movement tests for both back-healthy people and people with LBP (r = 0.47-0.73). In people with LBP the amount of lumbar motion in the 0% to 50% of movement time interval for both tests was significantly associated with functional limitation (r = 0.43-0.62). Conclusion: Lumbar movement patterns were similar between the two tests, and lumbar motion early in the movement of a functional test was related to self-report of functional limitation.