A novel registration method for total knee arthroplasty using a patient-specific registration guide

Total knee arthroplasty is a surgical method for replacing the entire knee joint by inserting an artificial knee implant into the distal femur and proximal tibia. To improve total knee arthroplasty outcomes, a registration process is essential for determining the exact location of the pre-determined bone-cutting area by calculating the positions and postures of the femur and tibia. In this paper, we suggest a patient-specific registration guide, which can drastically reduce the time and effort required for the registration process and provide real-time tracking potential. Because the patient-specific registration guide has the same surface shape as a pre-acquired 3-D model of the patient´s femur and tibia, the registration process can be achieved by fitting the registration guide onto the proper bone area. To verify the registration guide´s precision and accuracy, a digitizer and linear motion generator were used. The mean registration error of our method was 0.016mm, and this high accuracy can be obtained in less time than existing registration methods.