Objective To study the efficacy and repeatability of the Limb X Film Measuring Plate (LXMP)in clinical x film measurement of lengths and angles of limbs.Methods The LXMP was de- signed and manufactured for testing.Three known points in 9 templates were taken as golden standards.which were to be compared with measuring results of these projected points on the X film for testing efficacy of LXMP.Twenty-one patients with knees osteoarthritis were selected.The lengths and angles of their lower limbs were measured twice with the help of LXMP by an observer at different time intervals for testing in. Tra-observer repeatability.Two observers measured once on films at the same time for testing inter-observer repeatability.The correlation coefficients,mean absolute difierences between the repeated measurements,and error rate were calculated. Results The points on LXMP could be seen clearly on X film.Validation tests showed the differences in angle measurement between golden standards and measuring results for those pro- jeted points on the X film were insignificant.with mean absolute difference being O.10.-0.21,error rate being 0.12%-3.15%and r being close to 1.The differences in length measurement were insignificant ei- ther,with mean absolute differenee being 0.05 cm-0.16 cm.error rate being 0.12%-o.28%and r being close to 1.The intra-observer repeatability test for beth angles and lengths showed that r was close to I.mean absolute diffefences 0.55.and 0.1-0.37cm and error rate 0.3l%-O.97%.while the inter-observer re- peatability test showed that r was close to 1.mean absolute difierences o.39.and0.05-0.13cm and error rate O.16%-O.35%. Conclusion The Limb X Film Measuring Plate Can be used for accurately mcasuring limb lengths and angles with good efficacy and repeatability.

Objective: To investigate the quantitative relationship between liver fat content and bone mineral density (BMD) in middle-aged and elderly people. Methods: Totally 184 middle-aged and elderly community residents were recruited from March to June 2016, including 68 males and 116 females. MRI mDIXON-Quant and quantitative CT (QCT) examinations were performed to determine the content of liver fat and L1-L3 vertebral BMD. The subjects were divided into four groups according to the quartiles of liver fat content, and the baseline characteristics and other variables of different groups were were identified by using one-way analysis of Variance. The relationship between liver fat content and lumbar vertebral BMD was assessed with Spearman correlation and partial correlation analysis. Result: Subjects with higher hepatic fat content had lower spine BMD and higher body mass index (BMI), waist circumference. Liver fat content was negatively correlated with BMD (r=-0.203, P=0.003). After age and body weight were controlled, the negative correlation between liver fat content and BMD was still significant (r=-0.291, P<0.001), in males (r=-0.283, P=0.021) and in females (r=-0.210, P=0.025). Conclusion Liver fat content is negatively correlated with lumbar vertebral BMD in middle-aged and elderly people.