Leg XXXX and psychological variables predict outcome 2-3 years after lumbar fusion surgery.

@entity1 @entity717 @entity158 @entity615
Prediction studies testing a thorough range of psychological variables in addition to demographic, work-related and clinical variables are lacking in lumbar fusion surgery research. This prospective cohort study aimed at examining predictions of @entity717 , @entity615 and health-related quality of life (HRQOL) 2-3 years after lumbar fusion by regressing nonlinear relations in a multivariate predictive model of pre-surgical variables. Before and 2-3 years after lumbar fusion surgery, @entity1 completed measures investigating demographics, work-related variables, clinical variables, functional self-efficacy, outcome expectancy, fear of movement/(re)injury, mental health and @entity158 coping. Categorical regression with optimal scaling transformation, elastic net regularization and bootstrapping were used to investigate predictor variables and address predictive model validity. The most parsimonious and stable subset of pre-surgical predictor variables explained 41.6, 36.0 and 25.6% of the variance in @entity717 , @entity615 intensity and HRQOL 2-3 years after lumbar fusion. Pre-surgical control over @entity158 and HRQOL. Pre-surgical catastrophizing and leg @entity158 intensity significantly predicted @entity717 and @entity615 while the pre-surgical straight leg raise significantly predicted @entity615 . Post-operative psychomotor therapy also significantly predicted @entity717 while pre-surgical outcome expectations significantly predicted HRQOL. For the median dichotomised classification of @entity717 , @entity615 intensity and HRQOL levels 2-3 years post-surgery, the discriminative ability of the prediction models was of good quality. The results demonstrate the importance of pre-surgical psychological factors, leg @entity158 intensity, straight leg raise and post-operative psychomotor therapy in the predictions of @entity717 , @entity615 and HRQOL-related outcomes.
