Background and aims: The incidence of fragility fractures is increasing among community-dwelling postmenopausal women. Sarcopenia and obesity are significant risk factors for fractures, independent of osteoporosis. This study aims to investigate the prevalence of sarcopenia and obesity, as well as bone microstructure, according to osteoporotic status and fracture sites in older women with recent low-trauma fractures.

Methods: This cross-sectional study included 135 community-dwelling postmenopausal women aged 65 and older, evaluated within six months of experiencing a low-trauma fracture (resulting from a fall from standing height or less) occurring at the humerus, proximal femur, vertebrae, pelvis, forearm, or ankle. Participants were recruited either prospectively through the Fracture Liaison Service (FLS) at the Bone Disease Department of Geneva University Hospitals (HUG) (n = 90) or retrospectively from the Geneva Retirees Cohort (GERICO) (n = 45). Bone mineral density (BMD) and body composition were assessed using dual-energy X-ray absorptiometry (DXA), muscle strength was measured by handgrip strength (HGS), and bone microstructure was evaluated using high-resolution peripheral quantitative computed tomography (HR-pQCT).

Results and discussion: The prevalence of sarcopenia varied, with the overall prevalence across all definitions being 25%. It was significantly higher in osteoporotic women than in women with normal BMD (39% versus 6%, respectively, p = 0.014) and osteopenia (39% versus 20% respectively, p < 0.05). The prevalence of obesity was 24%, with particularly high rates observed among women with normal BMD (61%) and those with ankle or humerus fractures (43%, and 38%, respectively). Notably, 33% of women with major osteoporotic fractures (MOF) presented with normal BMD and without sarcopenia or obesity.

Conclusions: A significant proportion of women with apparent low-trauma MOF does not have osteoporosis nor alterations of body composition (sarcopenia or obesity). The determinants of fracture risk in these women remain unclear and further investigations are required to better address secondary fracture prevention in this context.