We investigated motor control strategies utilized by individuals with recurrent low back pain (rLBP) during active pain and remission periods as well as by back-healthy controls using the Balance-Dexterity Task. Nineteen young adults with rLBP were tested first when they were in pain and then again in symptom remission, and 19 matched controls were also tested. Trunk kinematic coupling and muscle co-activation were examined while participants performed the task by standing on one leg while compressing a spring with a maximum consistent force with the other leg. We found a decreased bilateral external oblique co-activation and a further reduced trunk coupling during the spring condition of the task compared to in a stable block condition in people with rLBP compared to back-healthy individuals. When individuals were in active pain, they exhibited more co-activation than when they were in remission, but the co-activation was not greater than in back-healthy individuals.

The authors have declared no competing interest.

This study was funded by the International Society of Biomechanics Matching Dissertation Grant awarded to H-JSS. LVD was supported by grant NIH/NICHD/NCMRR R01 HD 047709.

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Ethics committee/IRB of University of Southern California gave ethical approval for this work

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