Our overarching aim is to set up a procedural, analytic and developmental framework to establish CT of the central and peripheral skeleton as a clinically useful biomarker for skeletal strength in the clinical research and ultimately in the clinical setting. To accomplish this, the investigators will develop and validate phantoms and scanning procedures to standardize strength and structure measurements between different vQCT scanners and develop standardized acquisition, analytical, and quality control techniques for HR-pQCT with an emphasis on optimization for multi-center studies.

The investigators will develop new calibration phantoms to address inter and intra scanner variability in vQCT and HRpQCT. Phantom sets to evaluate inter-scanner disparity and determine corrections to apply to in vivo scan data in the multi-center settings. These methods will be validated in a multi-center phantom study and in a 120 patients

Inclusion Criteria:

• Healthy men and women
• must be able to lie down on bed

Exclusion Criteria:

• on wheel chair
• age above 80 years 0r less than 65 years

Healthy men and women aged 65-80