Calcaneous quantitative ultrasound measurements predicts vertebral fractures in idiopathic male osteoporosis.

Objectives: The aim of this study was to identify the differences in ultrasound bone variables (QUS) and to test the ability to discriminate male patients with and without vertebral fractures.

Methods: We therefore measured broadband ultrasound attenuation (BUA) and speed of sound (SOS) matched for bone mineral density (BMD) and vertebral deformity in idiopathic male osteoporosis.

Results: One hundred and seventeen men (age 56.6 range 27-78) were divided into three groups (osteoporosis n=25, osteopenia n=58 and age-matched control n=34) according to BMD T-score by WHO criteria. We found 66 patients (56%) with at least one vertebral deformity during the study. BMD and BUA did not differ, while SOS was lower in osteoporosis (p<0.001) and control group (p<0.001) between the patients with and without vertebral compression. Strong positive correlation was demonstrated between BUA and BMD (lumbar spine r=0.44, p<0.001, femoral neck r=0.56, p<0.001, radius r=0.40, p<0.001), while similar association between SOS and BMD values was not shown. There was no relationship between the BUA and vertebral fracture risk (Odds ratio: 1.14 95% CI: 0.80-1.61). However, the relative risk of vertebral fracture by SOS was 1.56 (95% CI: 1.08-2.62). Adjusting for age and BMI the risk of vertebral fracture did not change (odds ratio for SOS 1.50 95% CI: 1.02-2.22). After adjustment for BMD SOS was still associated with fracture risk at all measured sites (odds ratio: 1.43, 95% CI: 1.02-2.22; 1.41, 95% CI: 1.02-2.17 and 1.32, 95% CI: 1.02-2.0).

Conclusion: Our results suggest that BUA values are more closely related to density and structure while SOS values are able to predict fractures.