Abstract:

BACKGROUND: Three-dimensional CT reconstruction has been widely used in the classification of intertrochangeric fractures.
OBJECTIVE: To compare the reliability of currently used classification systems with three-dimensional CT and X-ray image for intertrochanteric fractures of the proximal femur. 
METHODS: Sixty-eight cases with intertrochanteric fractures of the proximal femur were subjected to CT and X-ray examination, and then the CT data were imported into the mimics10.0 software with dicom format to do the three-dimensional reconstruction. The three-dimensional data were classified independently by three experienced observers using the AO and Evans classification systems. The kappa value of AO and Evans classification groups of three observers was calculated when using the X-ray and three-dimensional CT image, as well as the kappa value of AO and Evans classification group between the observers when using the X-ray and three-dimensional CT image. Then the consistency among the three groups based on the kappa values was evaluated.
RESULTS AND CONCLUSION: Excluding 18 cases with unclear image, 50 cases obtained the satisfactory image. As for the typing based on the X-ray image and three-dimensional CT image, the kappa value in the three-dimensional CT image group was larger than that in the X-ray image group no matter which method we used; the the kappa value in the AO typing group was larger than that in the AO subgroup and Evans typing group no matter which method we used. Results indicate that the three-dimensional CT can be used more reliably to measure intertrochanteric fractures of the proximal femur than X-ray, and the reliability of the AO classification was more satisfactory than Evans.