Pattern of performance in workers with low back pain during a comprehensive motor performance evaluation.

Study Design: Tests of limb and back motor performance were administered to males with low back pain at the completion of a back-school program.

Objectives: The objective of the study was to determine the relationship between such motor performance and the propensity for abnormal illness behavior as indicated by the Waddell score.

Summary Of Background Data: Previous studies in similar subjects had revealed a nonbiologic pattern of lumbar strength and movement in back-school patients, and correlations between lumbar variables, Waddell score, and 'global' psychologic measures. This suggested that psychologic factors might affect motor performance in body segments unrelated to the low back in such patients.

Results: Mean performance of the group with a high Waddell score (indicating a propensity for abnormal illness behavior) was lower on all tests, including those that did not involve the low back, in comparison to the group with a low Waddell score (P < .01, sign test).

Conclusion: For all members of this population of patients, motor performance on dynamometry of any body segment does not necessarily reflect the maximum physical capacity.