Quantitative ultrasound imaging monitoring progressive disuse osteopenia and mechanical stimulation mitigation in calcaneus region through a 90-day bed rest human study

This study evaluates the longitudinal effect of a dynamic mechanical loading through the heel on human bone in vivo during 90-day bed rest, monitored by quantitative ultrasound (QUS) imaging and dual-energy X-ray absorptiometry (DXA) in localized regions of interests, i.e., calcaneus. A total of 29 bed rest individuals were evaluated (11 control and 18 treatment) with a brief (15-min) daily low-intensity (0.3 gg), high-frequency (30 Hz) dynamic mechanical stimulation countermeasure through vibrational inhibition of bone erosion (VIBE). Both QUS and DXA detected longitudinal bone density and quality changes. Ultrasound velocity (UV) decreased in the control group and increased in the group treated with low-intensity loading, with a relative difference of 1.9% and 1.6% at 60- and 90-day bed rest (p = 0.01) in VIBE over control groups. A trend was found in broadband ultrasound attenuation (BUA), with a VIBE benefit of 1.8% at Day 60 and 0.5% at Day 90 in comparison with control (p = 0.5). Bone mineral density (BMD) assessed by DXA decreased −4.50% for control individuals and −2.18% for VIBE individuals, showing a moderate effect of the mechanical intervention (p = 0.19). Significant correlations between QUS and DXA were observed, with a combined BUA and UV vs. BMD: r2 = 0.70. These results indicated that low-intensity, high-frequency loading has the potential to mitigate regional bone loss induced by long-term bed rest and that QUS imaging may be able to assess the...
Source: Journal of Orthopaedic Translation - Category: Orthopaedics Source Type: research