Pretreatment psychosocial variables as predictors of outcomes following lumbar surgery and spinal cord stimulation: A systematic review and literature synthesis

Background. In the multimodal treatment approach to chronic back pain, interventional back procedures are often reserved for those who do not improve after more conservative management. Psychological screening prior to lumbar surgery or spinal cord stimulation (SCS) has been widely recommended to help identify suitable candidates and to predict possible complications or poor outcome from treatment. However, it remains unclear which, if any, variables are most predictive of pain-related treatment outcomes. Objective. The intent of this article is to performa systematic review to examine the relationship between presurgical predictor variables and treatment outcomes, to review the existing evidence for the benefit of psychological screening prior to lumbar surgery or SCS, and to make treatment recommendations for the use of psychological screening. Results. Out of 753 study titles, 25 studies were identified, of which none were randomized controlled trials and only four SCS studies met inclusion criteria. The methodological quality of the studies varied and some important shortcomings were identified. A positive relationship was found between one or more psychological factors and poor treatment outcome in 92.0% of the studies reviewed. In particular, presurgical somatization, depression, anxiety, and poor coping were most useful in helping to predict poor response (i.e., less treatment-related benefit) to lumbar surgery and SCS. Older age and longer pain duration were also predictive of poorer outcome in some studies, while pretreatment physical findings, activity interference, and presurgical pain intensity were minimally predictive. Conclusions. At present, while there is insufficient empirical evidence that psychological screening before surgery or device implantation helps to improve treatment outcomes, the current literature suggests that psychological factors such as somatization, depression, anxiety, and poor coping, are important predictors of poor outcome. More research is needed to show if early identification and treatment of these factors through psychological screening will enhance treatment outcome.