No abstract

In a prospective controlled trial on 46 patients undergoing lumbar discectomy, three classes of variables (medical data including MRI-identified morphological abnormalities, general psychological factors and psychosocial aspects of work) were analyzed with regard to their predictive value for the outcome of lumbar disc surgery at 2 year follow-up. Multiple regression analyses were used to identify the best predictor variables of four different outcome measures (i.e. pain relief, reduction of disability in daily activities, return to work and surgical outcome). MRI-identified nerve root compromise and social support from the spouse were independent predictors of pain relief 2 years after surgery (R2 = 0.40, P < 0.01). Return to work 2 years after surgery was best predicted by depression and occupational mental stress (R2 = 0.36, P < 0.001). MRI-identified extent of herniation and depression were significant predictors of a good surgical outcome after lumbar discectomy (R2 = 0.61, P < 0.001). This study has demonstrated that the outcome of discectomy is critically dependent on which outcome variables are selected and that different sorts of predictor variables have a distinct influence on the various outcome variables. Obvious morphological alterations (i.e. disc extrusions, nerve root compromise) proved to be significant predictors of postoperative pain relief and improvement of disability in daily activities justifying a surgical treatment approach in these cases. The most important finding of this study was that return to work was not influenced by any clinical findings or MR-identified morphological alterations, but solely by psychological factors (i.e. depression) and psychological aspects of work (i.e. occupational mental stress).

Physical job characteristics and psychological aspects of work were more powerful than magnetic resonance imaging-identified disc abnormalities in predicting the need for low back pain-related medical consultation and the resultant work incapacity. However,the conclusions are still preliminary, and replication of the findings in larger and more representative study samples is needed.

In a 5-year longitudinal study, social support was investigated as a predictor of low back pain (LBP) in 46 initially asymptomatic individuals. Distinguishing between colleagues in general and the colleague one feels closest to, the authors analyzed constellations of support from supervisor (which had positive effects) and closest colleague (which had detrimental effects). Configural frequency analysis yielded a type characterized by high support from one's closest colleague and low support from one's supervisor at Time 1 and more LBP and disability at Time 2. Controlling for negative affectivity did not change findings. Results are interpreted in terms of being dependent on that one source of support in an unsupportive environment, which creates feelings of dependence, incompetence, and reciprocity obligations.