Psychologic influence on experimental pain sensitivity and clinical pain intensity for patients with shoulder pain

Pain-related fear and pain catastrophizing are 2 central psychologic factors in fear-avoidance models. Our previous studies in healthy subjects indicated that pain-related fear, but not pain catastrophizing, was associated with cold pressor pain outcomes. The current study extends previous work by investigating pain-related fear and pain catastrophizing in a group of subjects with shoulder pain, and included concurrent measures of experimental and clinical pain. Fifty nine consecutive subjects seeking operative treatment of shoulder pain were enrolled in this study (24 women, mean age = 50.4, SD = 14.9). Subjects completed validated measures of pain-related fear, pain catastrophizing, and clinical pain intensity and then underwent a cold pressor task to determine experimental pain sensitivity. Multivariate regression models used sex, age, pain-related fear, and pain catastrophizing to predict experimental pain sensitivity and clinical pain intensity. Results indicated that only pain-related fear uniquely contributed to variance in experimental pain sensitivity (beta = -.42, P < .01). In contrast, sex (beta = -.29, P = .02) and pain catastrophizing (beta = .43, P < .01) uniquely contributed to variance in clinical pain intensity. These data provide additional support for application of fear-avoidance models to subjects with shoulder pain. Our results also suggest that pain-related fear and pain catastrophizing may influence different components of the pain experience, providing preliminary support for recent theoretical conceptualizations of the role of pain catastrophizing.

This study provided additional information on how specific psychological variables potentially influence experimental and clinical pain. In this sample of subjects with shoulder pain, we replicated findings from our previous studies involving healthy subjects, as fear of pain was uniquely associated with experimental pain sensitivity. In contrast, pain catastrophizing emerged as the sole psychological variable related to clinical pain intensity.