Risk of hip fracture with hip or knee osteoarthritis: a systematic review

Osteoarthritis (OA) and hip fracture are two common musculoskeletal disorders associated with substantial societal and personal burden. The objective of this systematic review was to determine the association between hip or knee OA and risk of hip fractures in people aged 45 years and older as compared to people aged 45 years and older who do not have OA. We searched CINAHL, Cochrane Database of Systematic Reviews, Embase, OVID Medline, PUBMED, and SCOPUS for studies published up to July 2010 and conducted forward searches of included studies using Web of Science. Two reviewers independently screened articles for inclusion, extracted data, and evaluated the risk of bias of included studies using the Newcastle-Ottawa Scale. Eleven articles were included. Three investigated individuals with knee OA, two included adults with knee or hip OA, and six investigated adults with hip OA. We did not combine the hip OA or the knee OA studies in a meta-analysis due to the heterogeneity in: study populations and covariates adjusted for in estimates of association. Hip OA may be related to a decreased risk of hip fracture when considering crude estimates of association or estimates of association adjusted for a limited number of covariates, although not all studies found support for the presence of this association. The association between knee OA and hip fracture remains unclear. The presence of OA in the hip or knee should not act as an indication that assessment for hip fracture risk is unnecessary.