Dual-energy X-ray Absorptiometry of Both Hips Helps Appropriate Diagnosis of Low Bone Mineral Density and Osteoporosis

Abstract

Controversy still remains regarding the use of bilateral hip scanning when bone mineral density (BMD) is measured, and bilateral hip scanning is not mandatory in international guidelines for screening of osteoporosis. BMD of both hips and the lumbar spine was analyzed in 133 consecutive individuals. There were discrepancies between the lowest T-scores of both hips. Fourteen of the 133 participants (11%) were diagnosed with a poorer BMD status when the BMD of the hip of the dominant leg was analyzed. The total hip BMD of the dominant hip was lower than in the non-dominant hip, (p = 0.035), whereas there were no differences in the femoral neck area of the dominant and the non-dominant leg (p = 0.754). When classified by Z- or T-scores, there was consistency in 60 cases (45%) and inconsistency in 59 cases (44%). In 14 cases (11%), T- or Z-scores were the same, and it did not matter whether the non-dominant hip or the dominant hip had been chosen. A diagnostic discordance of 11% between the left and the right hip was observed when the lumbar spine was evaluated. The lowest Z- and T-scores of the hips were, in 44% of the cases, found in the hip of the assumed dominant leg. BMD measurements of both hips are recommended as clinical practice.

Keywords

• osteoporosis
• low bone mineral content
• bone mineral density
• dual-energy X-ray absorptiometry (DXA)