抄録
Objective: In total knee arthroplasty (TKA), precise placement of the tibial tray is necessary for good long-term results. However, the conventional tibial cutting guide may produce errors. Consequently, we have developed a new tibial cutting guide for TKA using a 3-dimensional (3D) templating system (Lexi Zed Knee, Japan). The accuracy of this system was evaluated by the image free Navigation System (Brainlab, Collibri)
Methods: Forty-one patients' knees were evaluated intraoperatively. Thirty-six patients' knees had osteoarthritis and five had rheumatoid arthritis, respectively. Computed tomography (CT) scanning of the lower extremities was undertaken for preoperative planning with use of the 3D templating system. The planning for the survey was carried out according to the CT free Navigation System. During the TKA procedure, this guide was calibrated according to the 3D preoperative plan and its coronal and sagittal alignments were measured by the navigation system. We defined valgus as positive in the coronal plane and posterior inclination as positive in the sagittal plane, respectively. The angle between the line perpendicular to the tibial anteroposterior axis and the transmalleolar axis was defined as tibial rotation.
Results: The average coronal alignment was 0.23±0.75 degrees (2∼−1 degrees). The average sagittal alignment was 0.35±0.85 degrees (2∼−1.5 degrees). The relationship between the alignment and tibial rotation was significant in the sagittal plane, but it was not in the coronal plane.
Conclusion: The accuracy of this guide in all knees was within two degrees. As a result, this new tibial cutting guide using the 3D templating system may be clinically useful in TKA procedures.
