Cross-sectional analysis of the association between fragility fractures and bone microarchitecture in older men: The STRAMBO study

Abstract

Areal bone mineral density (aBMD) measured by dual-energy X-ray absorptiometry (DXA) identifies 20% of men who will sustain fragility fractures. Thus we need better fracture predictors in men. We assessed the association between the low-trauma prevalent fractures and bone microarchitecture assessed at the distal radius and tibia by high-resolution peripheral quantitative computed tomography (HRpQCT) in 920 men aged 50 years of older. Ninety-eight men had vertebral fractures identified on the vertebral fracture assessment software of the Hologic Discovery A device using the semiquantitative criteria, whereas 100 men reported low-trauma peripheral fractures. Men with vertebral fractures had poor bone microarchitecture. However, in the men with vertebral fractures, only cortical volumetric density (D.cort) and cortical thickness (C.Th) remained significantly lower at both the radius and tibia after adjustment for aBMD of ultradistal radius and hip, respectively. Low D.cort and C.Th were associated with higher prevalence of vertebral fractures regardless of aBMD. Severe vertebral fractures also were associated with poor trabecular microarchitecture regardless of aBMD. Men with peripheral fractures had poor bone microarchitecture. However, after adjustment for aBMD, all microarchitectural parameters became nonsignificant. In 15 men with multiple peripheral fractures, trabecular spacing and distribution remained increased after adjustment for aBMD. Thus, in men, vertebral fractures and their severity are associated with impaired cortical bone, even after adjustment for aBMD. The association between peripheral fractures and bone microarchitecture was weaker and nonsignificant after adjustment for aBMD. Thus bone microarchitecture may be a determinant of bone fragility in men, which should be investigated in prospective studies. ß

Impaired bone microarchitecture at the distal radius in older men with low muscle mass and grip strength: The STRAMBO study

“…In addition, low muscle mass and strength are risk factors for fall and fracture, (45)(46)(47) whereas impaired bone microarchitecture was associated with fragility fractures. (18,19,(48)(49)(50) Thus, our data suggest that low muscle mass and strength contribute to the risk of fracture not only through the increased risk of falling but also through the impairment of bone microarchitecture and the consequent deterioration of bone strength. However, this speculation inferred from the cross-sectional analysis needs to be confirmed in a prospective study.…”

Quantitative imaging methods in osteoporosis

“…In trabecular bone, standard analysis includes quantifying structural properties of trabecular bone, such as bone volume fraction (BV/TV), which is derived from trabecular BMD (Tb.BMD), average number of trabeculae (Tb.N), average trabecular thickness (Tb.Th), and average trabecular separation (Tb.Sp) (76). Associations have been demonstrated for different HR-pQCT measurements at the tibia and radius for vertebral and any-type of fractures (77)(78)(79)(80)(81). Volumetric assessments with HR-pQCT also have added value in complex phenotypes such as diabetic bone disease.…”

Challenges in longitudinal measurements with HR-pQCT: Evaluation of a 3D registration method to improve bone microarchitecture and strength measurement reproducibility

“…This technique enables in vivo measurements at peripheral sites such as the distal radius and tibia, with a nominal isotropic voxel size of 82 μm. Bone microarchitecture parameters measured by HR-pQCT have been found to be associated with prevalent fracture in postmenopausal women and older men independently of areal bone mineral density (aBMD) [1][2][3][4][5]. Bone strength, estimated using micro-finite element analysis (μFEA), was also associated with prevalent fracture [6][7][8][9][10][11][12][13][14].…”