Background: Obesity and chronic low back pain (cLBP) are prevalent social and economic burdens with significant contribution to poor overall health. Previous research has viewed the two health conditions as separate research and clinical problems, but there is evidence of a relationship between them. However, combined obesity and cLBP research is limited and not well understood.
Aim: The aim of this thesis was to investigate the relationship between obesity and cLBP, and to explore the possible factors mediating that relationship.
Methods: A series of three explorative studies were employed to examine the relationship between obesity and cLBP. Study 1 investigated associations between BMI and exercise-related cLBP changes. Study 2 was an exploration of associations between adipose tissue distribution and cLBP. Study 3 investigated the effect of body mass distribution on a known postural task, and the possible mediation by movement of the lumbar spine or lumbar muscle endurance.
Results: BMI and BMI changes were not associated with cLBP, or successful predictors of cLBP changes. Regional adiposity, particularly the ratio of abdominal to lumbar adiposity, was associated with and a significant predictor of cLBP. Body mass distribution was shown to result in poorer postural task performance, but mediation by spinal movement or muscle endurance was not confirmed.
Discussion: No significant relationships between BMI and cLBP were identified, indicating the reliance on BMI as an obesity measure may not be justified. The established associations between regional adiposity distribution and cLBP may suggest that adipose tissue is a key contributor within the obesity-cLBP relationship. Although mediation of spinal movement or muscle endurance was not supported in the experimental context used, the link between body composition and mass distribution with cLBP was further confirmed.
Conclusion: The work of this thesis supports evidence of a link between obesity and cLBP. Adiposity and body mass distribution have been implicated in this relationship. Future studies should continue to explore possible mediating factors between obesity and cLBP in a variety of research contexts
