Intraosseous Doppler Ultrasonography to Study Skeletal Physiology: Exploratory Study Before Use in Space Physiology

"Timing for sub-protocol 1 (performed twice with 2-to-10-day interval): donning in supine position - rest 5 minutes - venous occlusion to 40 mmHg 3 minutes - rest 10 minutes - arterial occlusion to 200mmHg 2 minutes - post-occlusion period 10 minutes - rest 10 minutes - static handgrip 30% Maximum Voluntary Force 3 minutes - recovery 2 minutes and doffing.~Timing for sub-protocol 2 (performed once). First, two sequences of intraosseous ultrasonography are performed in 45° head-up tilt position, with 10-minutes rest between sequences: donning and rest 5 minutes - occlusion to 80 mmHg 2 minutes - rest 10 minutes - occlusion to 180 mmHg 2 minutes - rest 10 minutes. During the first sequence, ultrasonography probe is positioned between middle and lower third of tibia for cortical bone measurement; during the second - at distal epiphysis of the tibia for trabecular bone measurement. After ultrasonography, subject is sitting down for 10 minutes for computed tomography."