Nakamura T, Turner C H, Yoshikawa T, Slemenda C W, Peacock M, Burr D B, Mizuno Y, Orimo H, Ouchi Y, Johnston C C
Department of Medicine, Indiana University School of Medicine, Indianapolis.
J Bone Miner Res. 1994 Jul;9(7):1071-6. doi: 10.1002/jbmr.5650090715.
Despite lower femoral neck bone mass, Japanese women have a substantially lower incidence of hip fracture than North American whites. Reasons for this discrepancy were sought in a study of 57 Japanese and 119 white American women aged 50-79. All women were in good health. Bone mineral content (BMC) in the femoral neck, femoral neck length (NL), femoral neck angle (theta), cross-sectional moment of inertia (CSMI), safety factor (SF), and fall index (FI) were calculated using dual x-ray absorptiometry. Height and weight were greater in Americans than in Japanese (1.62 versus 1.52 m; p < 0.0001 and 66.0 versus 49.4 kg; p < 0.0001, respectively). Mean BMC in the femoral neck and CSMI were greater in Americans than in Japanese (3.91 versus 3.02 g; p < 0.0001 and 0.99 versus 0.57 cm4; p < 0.0001, respectively). NL was longer in Americans (5.6 versus 4.4 cm; p < 0.0001) and theta was larger in Americans (130 versus 128 degrees; p < 0.01), whereas SF and FI were less in Americans than in Japanese (3.41 versus 5.12; p < 0.0001 and 1.00 versus 1.40; p < 0.0001, respectively). These results indicate that despite lower bone mass, Japanese women have lower risks of structural failure in the femoral neck, attributable primarily to shorter femoral necks and, to a lesser degree, a smaller femoral neck angle. Geometric characteristics of the femoral neck in Japanese women are associated with their lower hip fracture risk, and the measurement of proximal femoral geometry, combined with bone mass, may provide further clinical information about the risk of hip fracture.
尽管日本女性股骨颈骨量较低，但她们髋部骨折的发生率远低于北美白人。在一项针对57名年龄在50至79岁之间的日本女性和119名美国白人女性的研究中，探寻了造成这种差异的原因。所有女性健康状况良好。使用双能X线吸收法计算股骨颈骨矿物质含量（BMC）、股骨颈长度（NL）、股骨颈角度（theta）、截面惯性矩（CSMI）、安全系数（SF）和跌倒指数（FI）。美国人的身高和体重高于日本人（分别为1.62米对1.52米；p<0.0001和66.0千克对49.4千克；p<0.0001）。美国人股骨颈的平均BMC和CSMI高于日本人（分别为3.91克对3.02克；p<0.0001和0.99平方厘米对0.57平方厘米；p<0.0001）。美国人的NL更长（5.6厘米对4.4厘米；p<0.0001），theta更大（130度对128度；p<0.01），而美国人的SF和FI低于日本人（分别为3.41对5.12；p<0.0001和1.00对1.40；p<0.0001）。这些结果表明，尽管骨量较低，但日本女性股骨颈结构破坏的风险较低，这主要归因于股骨颈较短，在较小程度上也归因于股骨颈角度较小。日本女性股骨颈的几何特征与她们较低的髋部骨折风险相关，股骨近端几何形状的测量结合骨量，可能会提供有关髋部骨折风险的更多临床信息。
