The Application of Three-dimensional CT in Congenital Dislocation of Hip Joint

Purpose To evaluate the applied value of the reconstruction of three dimentional CT on pre operation and post operation of congenital dislocation of hip joint(CDH). Methods Seventeen cases of CDH with 10 bilateral cases and 7 unilateral cases. To sum up, 26 sick hips were operated and 8 non operated hips were also obtained. The cases were examined by spiral CT (PQ6000,Picker Co),then the 3D pictures and relevant data measure were obtained by techniques of SSD, MIP and MPR on a workstation. Results 3D reconstruction were used to show femoral head, acetabulum and relationship of acetabulum and femoral head respectively. The technique of MPR was used to evaluate acetabulum index (AI) and femoral neck anteversion (FNA). The differences between pre and post operation were compared. Conclusion 3D CT of hip increases the information of imaging and affords the new technical support to related diagnosis and therapy of CDH. It will lead to a new model to deal with CDH: stereoscopic observation, three dimentional measurement and contraposed therapy.