Abstract
OBJECTIVE: To evaluate the evidence for the influence of physical workload on the occurrence of osteoarthritis (OA) of the hip. METHODS: We carried out a database search of Medline, Embase, and the Cochrane library to identify observational studies, and articles on the relationship between workload and hip OA were identified. Methodological quality of the selected studies was assessed using a standardized set of criteria. The outcome of each study was compared with its study characteristics and methodological quality score. Finally, a best-evidence synthesis was used to summarize the results from the individual studies. RESULTS: Two retrospective cohort studies and 14 case-control studies were included in this review. There was a slight negative, but not significant association between the study outcome and the methodological quality score. Overall, moderate evidence was found for a positive association, with an odds ratio of approximately 3, between previous heavy physical workload and the occurrence of hip OA. In addition, for the subcategories, i.e., > or = 10 years farming or lifting heavy weights (> or = 25 kg), moderate evidence was found for a positive relationship with hip OA. Possible selection of the populations studied may be partly responsible for the association we identified. CONCLUSION: The evidence for the influence of previous heavy physical workload on the occurrence of hip OA is moderate.