The CV for the aBMD measurements ranged from 0.5 to 3 %, depending on
application. Two subjects could not undergo total body, lumbar spine, or hip scan due to the weight limits of the Lunar Prodigy DXA [32]. The same device, software, and operator were used throughout the study. Cortical BIBW2992 bone geometry and volumetric BMD A peripheral quantitative computed tomography (pQCT) device (XCT-2000; Stratec Medizintechnik, Pforzheim, Germany) was used to scan the distal leg (tibia) and the distal arm (radius) of the nondominant leg and arm, respectively. A 2-mm-thick single tomographic slice was scanned with a voxel size of 0.50 mm. The cortical cross-sectional area (CSA, in square millimeter), endosteal and periosteal circumference (EC and PC, respectively, in millimeters), cortical thickness (in millimeters), and cortical volumetric density (in milligrams per cubic centimeter) were measured GS-1101 clinical trial using a scan through the diaphysis
(at 25 % of the bone length in the proximal direction of the distal end of the bone) of the radius and tibia. Tibia length was measured from the medial malleolus to the medial condyle of the tibia, and the length of the forearm was defined as the distance from the olecranon to the ulna styloid process. The CVs were <1 % for all pQCT measurements [32]. The same device, software, and operator were used throughout the study. A threshold-driven analysis was used (710 mg/cm3). Bone microarchitectural measurement A high-resolution
three-dimensional (3D) pQCT device (XtremeCT, Scanco Medical AG, Bassersdorf, Switzerland) was used to scan the ultradistal tibia and the ultradistal radius of the nondominant leg and arm, respectively, in 361 of the original 363 subjects. The right arm and leg of right-handed men was defined as their dominant side, while the left arm and leg of left-handed men was defined as their dominant side. Anatomically formed carbon fiber shells, designed for each type of limb (Scanco Medical AG, Bassersdorf, Switzerland), were used to immobilize the subject’s arm or leg during the scan. The measurements of the volume of interest in the ultradistal tibia and radius, 1 cm in the proximal direction Arachidonate 15-lipoxygenase and the whole cross-section in transversal direction, were carried out according to a standardized protocol previously described [35, 36]. Briefly, a reference line was manually placed at the center of the endplate of the distal tibia and distal radius. The first CT slice started 22.5 and 9.5 mm proximal to the reference line for the tibia and radius, respectively. One hundred ten parallel CT slices, with a nominal isotropic resolution (voxel size) of 82 μm, were obtained at each skeletal site, delivering a 3D representation of approximately sections of thickness 9 mm of both the tibia and radius in the proximal direction.