Correlation Between CT Value And Hip Fracture In Older Patients

Objective:By measuring CT values of spine and hip and analyzing the correlation between CT values and bone mineral density T values,the hip bone mineral density level was indirectly evaluated.To provide data and theoretical basis for clinical screening of high risk population of hip fracture,improve the accuracy of hip fracture risk prediction,and prevent hip fracture as early as possible.Materials and Methods:All patients included in this study received ordinary CT scanning and were divided into hip fracture group and no fracture control group.A doctor animated the region of interest(ROI)on the CT images of two groups of patients and calculated the CT value.The intraclass correlation coefficient(ICC)was used to evaluate the retest reliability of doctors,ICC>0.75 was included in the analysis,and Pearson correlation coefficient was used to evaluate the correlation between CT values of different parts and T values of hip bone mineral density.Using the receiver operating characteristic curve(ROC)and the area under the curve(AUC)to evaluate the ability of CT value to predict hip fracture,evaluate its prediction sensitivity and specificity,and calculate the diagnostic cut-off value.Results:1.A total of 164 patients were included in this study,including 80 in the hip fracture group and 84 in the control group.There was no significant difference in height,weight,BMI,smoking and drinking between the two groups.2.CT values are highly correlated with each of the three repeated measurements.3.CT values of L1,femoral head and femoral neck:CT values of L1,femoral head and femoral neck in the fracture group were significantly lower than those in the control group(117.4±26.1 vs.171.0 ± 29.7;192.3±37.6 vs.272.1±52.1;110.9±21.6 vs.167.6±30.9).DXA T value in fracture group was also significantly lower than that in control group(-2.2±0.43 vs.-1.5±0.48,P<0.001).The CT values of L1(r=0.848,P<0.0001),femoral head(r=0.936,P<0.0001),femoral neck(r=0.869,P<0.0001)were significantly correlated with hip BMD T value.4.The AUC of ROC curve of hip fracture predicted by L1 CT value was 0.906,the sensitivity was 0.738,the specificity was 0.938,and the cut-off value was 156 HU;The AUC of ROC curve predicted by CT value of femoral head was 0.889,the sensitivity was 0.725,the specificity was 0.938,and the cut-off value was 264 HU;The AUC of ROC curve predicted by CT value of femoral neck was 0.936,the sensitivity was 0.940,the specificity was 0.875,and the cutoff value was 123HU.The AUC of bone mineral density T-value predicting the ROC curve of hip fracture was 0.864,the sensitivity was 0.702,the specificity was 0.875,and the cutoff value was-1.8.Conclusion:1.Through the analysis of CT value of L1 vertebral body,femoral neck and femoral head cancellous bone and T value of hip bone mineral density,the results suggest that there is a positive correlation between them.CT value increases with the increase of T value,and CT value measurement can indirectly reflect the level of bone mineral density.2.By comparing the CT value between the elderly hip fracture group and the control group,the CT value of the elderly hip fracture group is significantly lower than that of the control group,and the CT value has good sensitivity and specificity in predicting hip fracture.