Pain severity and mobility one year after spinal cord injury: a multicenter, cross-sectional study

BACKGROUND: Following a spinal cord injury, patients are often burdened by chronic pain. Preliminary research points to activation of the motor cortex through increased mobility as a potential means of alleviating postinjury chronic pain. AIM: The aim of this study was to assess the relationship between pain severity and mobility among patients who have sustained a traumatic spinal cord injury while controlling for clinically-relevant covariates. DESIGN: A multi-center, cross-sectional study. SETTING: The SCIMS is composed of 14 centers, all located in the United States and funded by the National Institute on Disability and Rehabilitation Research (NIDRR). POPULATION: The study cohort included 1980 patients who completed the one-year SCIMS follow-up assessment between October 2000 December 2013. METHODS: A multi-center, cross-sectional study was performed to assess the impact of mobility on self-reported pain using information from 1980 subjects who sustained a traumatic spinal cord injury and completed a year-one follow-up interview between October 2000 and December 2013. Patient information was acquired using the Spinal Cord Injury National Database, compiled by the affiliated Spinal Cord Injury Model Systems. Analyses included a multivariable linear regression of patients' self-reported pain scores on mobility, quantified using the CHART-SF mobility total score, and other clinically relevant covariates. RESULTS: After controlling for potential confounders, a significant quadratic relationship between mobility and patients' self-reported pain was observed (P=0.016). Furthermore, female gender, "unemployed" occupational status, paraplegia, and the presence of depressive symptoms were associated with significantly higher pain scores (P<0 02 for all variables). Statistically significant quadratic associations between pain scores and age at injury, life satisfaction total score, and the CHART-SF occupational total subscale were also observed (P <= 0.03 for all variables). CONCLUSIONS: Among patients with moderate to high levels of mobility, pain scores decreased with increasing mobility.