Predicting low back pain patients' response to lumbar sympathetic nerve blocks and interdisciplinary rehabilitation: the role of pretreatment overt pain behavior and cognitive coping strategies.

The current study examined the ability of overt pain behavior and cognitive coping strategies to predict low back pain patients' subsequent response to lumbar sympathetic nerve blocks and interdisciplinary pain rehabilitation. Seventeen chronic low back pain patients participated in the study. Each was assessed regarding pretreatment overt pain behavior, cognitive coping strategies and pretreatment outcome measures. They then received interdisciplinary pain rehabilitation including lumbar sympathetic blocks. Findings showed that patients exhibited significant improvement in posttreatment outcome measures and specific responses to nerve blocks. Regression analyses revealed that cognitive coping strategies failed to demonstrate any predictive utility across blocks or outcome measures. In contrast, overt pain behavior observed during the first block was highly predictive of acute and chronic subjective pain associated with initial and subsequent blocks, as well as posttreatment outcome measures for interdisciplinary pain rehabilitation. The more overt pain behavior observed during block 1, the more acute and chronic subjective pain observed across blocks and the poorer subsequent treatment outcome measures. This predictive capability was demonstrated over and above that of other pretreatment measures such as pain duration, number of surgeries, and receipt of economic compensation. Given the small sample size results were viewed with caution. It was concluded, however, that overt pain behavior might well be a significant predictor variable for specific and combined interdisciplinary pain rehabilitation techniques.