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.