The prevalence of osteoporosis in patients with severe hip and knee osteoarthritis awaiting joint arthroplasty.

BACKGROUND

the presence of osteoporosis in patients with hip and knee osteoarthritis (OA) has important implications for understanding disease progression and providing optimal surgical and medical management.

OBJECTIVE

to determine the prevalence of osteoporosis among patients with osteoarthritis awaiting total knee arthroplasty or total hip arthroplasty aged between 65 and 80 years.

DESIGN

cross-sectional observational study.

SETTING

tertiary referral centre in Newcastle upon Tyne, UK.

SUBJECTS

patients with osteoarthritis awaiting total knee hip arthroplasty aged between 65 and 80 years.

METHODS

lumbar spine, bilateral femoral and forearm bone mineral density (BMD) measurements were obtained using dual-energy X-ray absorptiometry.

RESULTS

the cohort consisted of 199 patients with a mean age of 72 years (SD 4), and 113 (57%) were women. The overall rate of osteoporosis at any site was 23% (46/199) and a further 43% (85/199) of patients would have been classified as osteopaenic according to World Health Organization criteria. Osteoporosis was more commonly detected in the forearm (14%) than the lumbar spine (8.5%) and proximal femur of the index side (8.2%).

CONCLUSIONS

in summary, a significant proportion of patients with end-stage OA have osteoporosis but this diagnosis may be missed unless BMD measurements are performed at sites distant from joints affected by OA.