ABSTRACT
[Objective]To provide a precise individualized design proposal for locating acetabular prosthesis by means of 3D reconstruction,reverse engineering software and rapid prototyping technology.[Method]3D CT scan pelvis image data were obtained from six patients,which displayed osteonecrosis of femoral head on one side.The data were transferred via a DICOM network into a computer workstation.A 3D model of hip was reconstructed using Amira 3.1 software,and saved in STL format.Then the 3D model was imported into Imageware 12.0 software.The normal hip joint centre of abnormal side was determined and the best orientation of the prosthesis(which was central axial ray of acetabula)was defined using reverse engineering.Locating template was designed according to the anatomic features of the acetabula and the central axial ray.Entity model was produced by rapid prototyping technology.The orientation of the prosthesis was located by matching the model to acetabular concavity at operation.[Result]By measuring postoperative standard hip anteroposterior film,the abduction angle of acetabular prosthesis was(46.00?2.49)? and the anteversion angle was(15.68?2.85)?.The expected result was obtained.[Conclusion]The navigation template designed and constructed preoperatively can provide precise location for acetabular prosthesis and avoid procedural errors at operation.