目的　探讨儿童青少年骨体重负荷对腰椎和髋部骨矿含量 (BMC)、骨密度 (BMD)的影响 ,并比较两指标的优次。方法　应用DXAQDR - 4 5 0 0A型扇形束骨密度仪测量长沙地区 5 4 7例 6～ 15岁儿童青少年腰椎前后位 ,仰卧侧位及髋部股骨近端的骨量。结果　不论男女 ,儿童青少年体重、体块指数 (BMI)、腰椎及髋部BMC和BMD随年龄增加而增加 (P <0 .0 5或 0 .0 1) ;体重与BMC的相关性较体重与BMD的相关性更密切 ;髋部及腰椎各部位体重标准化BMC随年龄增加而增大 ,而髋部和腰椎各部位体重标准化BMD随年龄增加反而减小。结论　 6～ 15岁儿童青少年腰椎及髋部BMC指标判断骨强度优于BMD ,尤以髋部及腰椎侧位BMC为佳。

Objective This study aims to investigate the influences of body weight on bone mineral content (BMC) and bone mineral density (BMD) of lumbar spines and proximal femur in healthy children and adolescents aged 6-15 years and to compare the differences between BMC and BMD. Methods The BMC and BMD of anteroposterior and supine lateral lumbar spines and proximal femur in 547 healthy children and adolescents from Changsha region were measured by DXA QDR-4500A fan beam bone densitiometry. Results The body weight, body mass index (BMI), BMC and BMD of lumbar spines and proximal femur increased with age in both male and female children and adolescent(P< 0.05 or 0.01). The body weight was more correlated with BMC than with BMD. The BMC adjusted by weight of lumbar spines and proximal femur increased,while the BMD adjusted by weight of them decreased with age. Conclusions It is suggested that BMC is more coincident with the property of bone intensity in terms of mechanics so BMC is a better marker than BMD for the assessment of bone intensity in children and adolescents aged 6-15 years.