Bone Mineral Density Changes in the Hip and Spine of Men and Women 1-Year After Primary Cemented Total Knee Arthroplasty: Prospective Cohort Study.

This study evaluated age- and sex-adjusted changes in total hip and spine bone mineral density (BMD) within 1 year of total knee arthroplasty (TKA) using a prospective, longitudinal cohort with a one-year follow-up. Preoperatively, subjects underwent routine bone mineral densitometry of their hip and spine, which was repeated 12 months postoperatively. Of 108 subjects, 97 (90%) completed BMD testing. Total hip BMD decreased significantly over time (1.80% change, P<0.001) with females losing more than males (P<0.001). The pattern was similar, but attenuated in the spine. Subjects undergoing primary cemented TKA had significant bone loss in the hip within 12 months, beyond that expected with age.