Differences among outcome measures in occupational low back pain.

The rate of recurrence in low back pain patients has been reported as high as 70%; therefore, it is believed that researchers have a poor understanding of low back pain recovery. To enhance our understanding of recovery, a large cross-sectional study was conducted to compare outcome measures of return to work, impairment of activities of daily living, pain symptoms, and functional performance probability. A total of 208 workers were examined. The percentage of workers recovered based on return to work criteria was 99% compared to 25% for impairment of activities of daily living, 17% for symptoms, and 12.5% for functional performance probability. Single functional performance measures of range of motion, velocity, and acceleration had recovery rates of 59, 13, and 10%, respectively. It appears that all these criteria are measuring very different parameters of low back pain recovery. The residual loss in functional performance may indicate a decreased tolerance to physical demand providing potential insight for why recurrent low back pain rates are high.