Difference in Bone Mineral Quality Between Caucasians and African Americans

Introduction: African-Americans have a lower fracture risk than Caucasians [1] but the reason for this difference remains unclear. Arguments have been offered that fracture risk is governed by extrinsic factors [2, 3], e.g., differences in bone size, or intrinsic factors [4-6], e.g. differences in bone mineral density (BMD) [7, 8]. The latter finding, which was primarily obtained from dual energy X-ray absorptiometry (DXA), generally concluded that bone from African-Americans had a greater BMD than bone from Caucasians. Other mineral density assessment techniques, notably quantitative backscatter electron imaging (qBEI) and computerized tomography (CT), provided data that suggested the opposite [9, 10]. To gain new insight regarding the race-related intrinsic material properties of bone, the present study sought to test the null hypothesis that there are no differences in the relative quantity or quality of trabecular bone mineral obtained from African-American and Caucasian subjects.