Computer-aided reconstruction of hip joint in revision arthroplasty

Geometric revision reconstruction of the hip joint of a female patient is presented. Because of extensive bone resorption and strong bone obstruction, we decided to employ a custom–made prosthesis not only in the pelvis but also in the femur. The custom prosthesis design and manufacturing processes were carried out with the aid of computed tomography (CT), a system of tomographic image processing, a computer–aided design (CAD) system and a computer–aided manufacturing (CAM) system. The process included tomographic measurements of the patient’s hip joint, conversion of the CT images, geometrical modelling of the femur and pelvis in the CAD system, prostheses design, virtual simulation of the reconstructed acetabulum, determination of prosthesis matching, and manufacturing on a CNC machine. The outcome of this engineering process was a total hip arthroplasty (THA) surgical operation.