Pain acceptance potentially mediates the relationship between pain catastrophizing and post-surgery outcomes among compensated lumbar fusion patients

PURPOSE Chronic low back pain is highly prevalent and often treatment recalcitrant condition, particularly among workers' compensation patients. There is a need to identify psychological factors that may predispose such patients to pain chronicity. The primary aim of this study was to examine whether pain acceptance potentially mediated the relationship between pain catastrophizing and post-surgical outcomes in a sample of compensated lumbar fusion patients. PATIENTS AND METHODS Patients insured with the Workers Compensation Fund of Utah and who were at least 2 years post-lumbar fusion surgery completed an outcome survey. These data were obtained from a prior retrospective-cohort study that administered measures of pain catastrophizing, pain acceptance, mental and physical health, and disability. RESULTS Of the 101 patients who completed the outcome survey, 75.2% were male with a mean age of 42.42 years and predominantly identified as White (97.0%). The majority of the participants had a posterior lumbar interbody fusion surgery. Pain acceptance, including activity engagement and pain willingness, was significantly correlated with better physical health and mental health, and lower disability rates. Pain catastrophizing was inversely correlated with measures of pain acceptance (activity engagement r=-0.67, p<0.01, pain willingness r=-0.73, p<0.01) as well as the outcome measures: mental health, physical health, and disability. Pain acceptance significantly mediated the relationship between pain catastrophizing and both mental and physical health and also the relationship between pain catastrophizing and disability. CONCLUSION This study demonstrated that the relationship between pain catastrophizing and negative patient outcomes was potentially mediated by pain acceptance. Understanding this mediating relationship offers insight into how pain acceptance may play a protective role in patients' pain and disability and has potential implications for pain treatments.