The proposed biopsychosocial model assumes that LBP-related chronic disability is possibly, in some cases, a stress-related disorder. Its empirical verification in LBP could particularly improve the understanding of the interrelationships between certain variables.

This study tested an integrative occupational stress-model with a sample of 209 palliative-care nurses who responded to a survey. Using two hierarchical regression models, including the Job Demand-Control-Support model, the Effort-Reward Imbalance model, and specific palliative care stressors and resources, results showed that best predictors of job satisfaction were job demand, effort, reward, and people-oriented culture, whereas best predictors of emotional distress were reward, professional and emotional demands, and self-efficacy. Finally, using structural equation modeling, a two-factor occupational stress-model was developed, distinguishing job demands and job resources. Results emphasize the importance of using comprehensive and situation-specific models to study stress in specific worker populations, studying positive outcomes in stress research, and increasing job resources at work to prevent stress.

The study is devoted to the prediction of crack path direction in polymodal fatigue. First experimental and theoretical results published in the literature are reviewed. It is shown that proportional and nonproportional loading conditions should be distinguished. Then, the experimental results obtained in cyclic Mode III and biaxial nonproportional Modes I + II loading are presented. These tests were carried out on two alloy steels and an aluminum alloy. The biaxial tests were performed on cruciform type specimens. In Mode III loading, it is shown that, at low applied torque, the crack surface adopts a “factory-roof” appearance with facets characteristic of local Mode I extension. It is suggested that the flat surfaces corresponding to apparent macroscopic Mode III extension observed in this study as in other ones might be an artefact. In Modes I + II loading, it is shown that the two investigated materials exhibit very different crack bifurcation angles. The results are discussed in terms of possible extended forms of the maximum tangential stress criterion, ΔkImax*, KImax* and (da/dN)max. It is shown that, as a general rule, the latter criterion gives results in better agreement with the experiments. The difficulties associated with crack closure effect are also shortly discussed.

The Chronic Pain Coping Inventory (CPCI) was developed to assess eight behavioral coping strategies hypothesized to be important for pain adaptation. But the predictive validity of the CPCI has yet to be tested in a longitudinal study. Here, 321 workers on sick leave after a work accident affecting the low back pain (LBP) region completed the CPCI during the subacute stage (T1) of LBP as well as the Catastrophizing scale of the Coping Strategies Questionnaire (CSQ). Disability, pain intensity and depressive mood were assessed simultaneously as well as 6 months later (T2). Work status was also determined at follow-up. Hierarchical regression analyses revealed that the CPCI (Guarding scale) predicted T1 disability and T2 disability (Relaxation scale), but T1 disability was the best predictor of T2 disability. For T1 pain intensity, the CSQ's Catastrophizing dimension was the best predictor and the CPCI Guarding scale added a small contribution. T1 pain intensity was the best predictor of T2 pain intensity. Catastrophizing and Guarding were the most strongly associated with depressive mood at T1 but at T2, only depressive mood at T1 predicted this same variable. Results indicated also that the Guarding and Catastrophizing scales were able to predict future work status. The present study clearly reveals the usefulness of Guarding from the CPCI and Catastrophizing from the CSQ, when predicting different outcomes of adjustment to low back pain.