title: Factor of risk for hip fracture in normal Chinese men and women in Taiwan.
abstract: We have investigated the age-related change in factor of risk (Phi) for the proximal femoral load during free fall in 548 females and 240 males aged 21-79 years. These individuals were divided into either young (age <50 years) or old group (age >/=50 years). Another 26 females with hip fractures were included for comparison. The bone mineral density (BMD) of proximal femoral neck was measured by a Norland XR-26 dual-energy X-ray absorptiometer (DXA). The estimated fracture load (L) of femoral neck was calculated from the BMD with the regression equation derived by Courtney et al. [2,3] and estimated fall force (F) by body weight and height according to the regression equation derived by Nakamura et al. [6] respectively. Phi was defined as the quotient of F/L. The results showed an age-related decrease of BMD (P < 0.001) in both genders corrected for weight and height. By multiple linear regression analysis, the F decreased significantly with aging corrected for BMD in old males (partial r = -0.255, P < 0.01) and increased with aging in all females (young, partial r=0.287, p < 0.001; old, partial r = 0.252, P < 0.001). L decreased significantly with aging corrected for height and weight in males (young, partial r = -0.401, P < 0.01; old, partial r = -0.178, P < 0.05) and females (young, partial r = -0. 168, P < 0.05; old, partial r = -0.459, P < 0.001). However Phi decreased with aging in young males (P < 0.01) and females (young: P < 0.001, old: P < 0.001). Phi increased in old women but not in old men, and was higher in old women compared with old men. The 26 patients with hip fractures had a significantly higher Phi value than 85 age-matched women. In conclusion, Phi may provide a comprehensive comparison of the risk of hip fracture in the elderly population.
authors.affiliation: Department of Orthopedics, College of Medicine, National Taiwan University, # 7, Chung-Shan South Rd., 100 Taipei, Taiwan, Republic of China.
authors.forename: R S
authors.initials: RS
authors.lastname: Yang
authors.forename: T K
authors.initials: TK
authors.lastname: Liu
authors.forename: Y S
authors.initials: YS
authors.lastname: Hang
authors.forename: P U
authors.initials: PU
authors.lastname: Chieng
authors.forename: K S
authors.initials: KS
authors.lastname: Tsai
mesh_terms: D015502:Absorptiometry, Photon; D000058:Accidental Falls; D000328:Adult; D000368:Aged; D000375:Aging; D044466:Asian People; D001827:Body Height; D001835:Body Weight; D015519:Bone Density; D002681:China / Q000208:ethnology; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging; D006620:Hip Fractures / Q000208:ethnology / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D013624:Taiwan / Q000453:epidemiology; D016474:Weight-Bearing / Q000502:physiology