Motor control deficits are common in chronic/recurrent low back pain (LBP) 3,13,19,24,33,34,36 and include altered paraspinal muscle function. 4,5,19,29 Recovery from LBP does not ensure restoration of spine function or movement, and recurrent LBP involves persistent alterations of motor control, including modified coordination between short/deep (eg, multifidus) and long/ superficial (eg, thoracic erector spinae) paraspinal muscles, with a tendency to contract these muscles en masse rather than to activate
T T BACKGROUND:Control deficits of back muscles and trunk movement are common in chronic/recurrent low back pain (LBP). A reliable clinical test to rate an individual's ability to dissociate lumbopelvic movement from the thoracolumbar region has been described. This test rates the performance quality of 5 key aspects against criterion standards.
T T METHODS: Concurrent validity was examinedby comparison of clinical test scores (overall score and each individual criterion) against spine kinematics. Discriminant validity was evaluated by comparison of scores between pain-free controls and participants with LBP. A receiver operating characteristic curve was calculated to determine the optimal cutoff or score to differentiate between good and poor performers.
T T RESULTS:Concurrent validity was supported by the significant correlation between the total score and motion of the T5 vertebra relative to the S1 vertebra (P<.05). Scores for some (4 correlations of 14 measures) but not all individual criteria were correlated with the kinematic features that each criterion was expected to reflect. Discriminant validity was supported by higher test scores for pain-free controls than for participants with LBP after 2 minutes of training (P = .045). Scores of less than 5.5 were more prevalent in the LBP group (pretraining LBP versus control, 72% versus 35%; P = .008; posttraining LBP versus control, 48% versus 16%; P = .018).
T T CONCLUSION:This preliminary study of concurrent and discriminant validity of the test provides a foundation to further investigate its utility to characterize thoracolumbar movement patterns in individuals with LBP.