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Date of Award
Doctor of Philosophy (PhD)
Occupational studies have shown that people who stand for prolonged periods of time have an increased risk for the development of low back pain (LBP). An induced-LBP paradigm has been developed to examine the factors that contribute to LBP development in healthy people without a history of LBP. Based on whether or not LBP is experienced during standing participants are classified into pain developer (PD) or non-pain developer (NPD) groups. The primary purposes of this dissertation project were to examine in NPDs and PDs 1) posture during standing, 2) sensory processing status, 3) psychological factors, and 4) the ability of the preceding biological and psychological factors to predict the course of LBP in standing in PDs.
In chapter 2, posture was examined at baseline and on average during standing between NPDs and PDs. We found that both groups stood in similar postures during the 2 hours of standing. Neither the lumbar curvature angle nor the horizontal distance measure between T6 and L3 were found to be risk factors for the development of LBP. In terms of relationships between postures measures and LBP, we found that a greater horizontal distance, indicative of greater loading on the posterior elements of the spine, was positively associated with LBP reports. In chapter 3, we examined sensory processing in NPDs and PDs. There were no differences between groups for thermal thresholds, pressure pain thresholds, wind-up ratio, or conditioned pain modulation. In chapter 4, we examined psychological factors in NPDs and PDs, and the relationship between psychological factors and reported LBP. We found no differences in scores on fear of pain or pain catastrophizing measures between NPDs and PDs, and no relationship between psychological factors and LBP. In chapter 5, we utilized hierarchical linear modeling to determine the biological and psychological factors that predicted the development and course of LBP in standing in PDs. Trunk to height ratio and the Fear of Pain Questionnaire minor subscale scores were significant between-individual predictors of the course of LBP in PDs. In addition, time was identified as a significant predictor within-individuals. As time increased, LBP intensity tended to increase.
The results of this dissertation support the study of LBP using the multidisciplinary biopsychosocial model. Significant biological and psychological factors contributing to either the development or course of LBP with prolonged standing were identified. Sensory processing was eliminated as a contributing factor to LBP. Further work is needed to determine if anthropometrics, standing posture, and fear of pain also contribute to LBP in other healthy populations.
Chair and Committee
Linda R. Van Dillen
Michael J. Strube, Ann Marie Dale, Simon Haroutounian, Michael J. Mueller,
Hwang, Ching-Ting, "Biological and Psychological Factors Contributing to the Development and Course of Low Back Pain in Prolonged Standing" (2018). Arts & Sciences Electronic Theses and Dissertations. 1539.
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