Relationship between Locomotive Syndrome and Cortical Bone Thickness and Trabecular Bone Density in a Community-dwelling Postmenopausal Population.

Objectives: We investigated the association between locomotive syndrome (LS), cortical bone thickness, and trabecular bone density in community-dwelling postmenopausal women. Methods: In total, 1405 postmenopausal women aged ≥50 years were analyzed from the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study. LS was assessed using the stand-up test, 2-step test, and the 25-question Geriatric Locomotive Function Scale. The cortical bone thickness and trabecular bone density at the radius were assessed using a quantitative ultrasound device capable of distinguishing between the cortical and trabecular components. Demographic and bone-related variables were compared between participants with and without LS using the t-test and chi-squared test. Multivariate linear regression analyses were performed with cortical bone thickness or trabecular bone density as the dependent variable and LS status as the independent variable, after adjusting for age and lifestyle factors. Results: Of all participants, 892 (63.5%) had LS. Multiple linear regression analysis showed that LS was independently associated with reduced cortical bone thickness (β = -0.076, p = 0.001) and trabecular bone density (β = -0.109, p <0.001). This association was statistically significant in both age groups (<65 and ≥65 years). Conclusions: In postmenopausal women, LS was independently associated with cortical bone thinning and trabecular bone loss. Our findings suggest that bone quality may play an important role in the prevention and management of LS, indicating that future strategies should consider both bone density and bone quality.