DEVICE: CTXA Hip Extended Reference Data (B052DICTXAHIPEXTDB0)

Device Description: The CTXA Hip Extended Reference Data is an accessory to the CTXA Hip Bone Mineral Densitometer. The CTXA Hip Extended Reference Data is used within the CTXA Hip module to calculate T-scores and percent young normal for any patient, and Z-scores for patients age 20-80 for BMD estimates made using the CTXCA Hip module. TThe intended use of the CTXA Hip Extended Reference Data accessory for the CTXA Hip Bone Mineral Densitometry module is to provide a context for the clinical interpretation of a patient's proximal femur BMD estimates. The use of a reference data set and the interpretation of parameters derived by the CTXA Hip module when comparing patient-specific BMD estimates to the installed and selected reference data set is at the discretion of the physician. The predicate K002113 CTXA Hip Bone Mineral Densitometer Module (CTXA Hip) provides estimates of bone mineral content (BMC) and bone mineral density (BMD) values similar to those obtained from DXA devices. These BMD estimates from the predicate device are compared to a reference database of age 20-39 US Caucasian females to calculate T-scores and percent young normal for patient BMD estimates and Z-scores for patient BMD estimates for ages 20-39. The current CTXA Hip Extended Reference Data is an accessory to CTXA Hip that also is used to calculate T-scores and percent young normal, and also is used to calculate Z-scores for ages 20-80. The CTXA Hip BMD estimates referenced to the CTXA Hip Extended Reference Data reference population are used as an aid to the physician in identifying patients with low bone mineral density and as an aid in determining a patient's fracture risk. BMD estimates obtained with CTXA Hip with Extended Reference Data accessory are identical to BMD estimates obtained with the predicate CTXA Hip. T-scores calculated with CTXA Hip with Extended Refecrence Data accessory are slightly less negative or less positive than those calculated with CTXA Hip,approximately 0.1-0.2 T-score units.