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Published on: May 5, 2023
Can Cadaver Testing Replicate In Vivo Kinematics of Total Knee Arthroplasty?
Kenichi Kono1, Takaharu Yamazaki, Teruya Ishibashi
1From the Department of Molecular Medicine Arthritis Research, The Scripps Research Institute, La Jolla, CA (Kono and D'Lima), the Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan (Kono), the Department of Orthopaedic Biomaterial Science, Osaka University Graduate School of Medicine, Suita, Osaka, Japan (Kono, Ishibashi, Tamaki, Sugamoto, and Tomita), the Department of Information Systems, Faculty of Engineering, Saitama Institute of Technology, Fukaya, Saitama, Japan (Yamazaki), the Department of Orthopaedic Surgery, Osaka Medical Center, Chuo-ku, Osaka, Japan (Iwamoto), the Department of Engineering, Osaka University Graduate School of Medicine, Suita, Osaka, Japan (Sugamoto), and the Master Course of Health Sciences, Graduate School of Health Sciences, Morinomiya University of Medical Sciences, Suminoe Ward, Osaka, Japan (Tomita).
Introduction:
Whether the kinematics of cadaveric knees recreate those of the patient's knees after total knee arthroplasty (TKA) remains unknown. This study compared in vivo and in vitro fluoroscopic kinematics of knees after TKA during knee bending using the same implant design.
Methods:
Patients who had undergone cruciate-retaining and cruciate-substituting total knee arthroplasty (CR-TKA and CS-TKA) did squatting motions. Fresh-frozen human cadaveric knees were tested under dynamic closed-chain knee extension in an Oxford knee rig. Fluoroscopic kinematics were measured in vivo and in vitro using a 2-dimensional to 3-dimensional registration technique. The axial rotation angle and anterior-posterior translation of medial and lateral contact points of the femoral implant relative to the tibial implant was evaluated in each flexion angle.
Results:
No notable differences in the axial rotation angles were found between in vivo and in vitro measurements in both CR-TKA and CS-TKA. In early flexion, the medial and lateral contact points in cadaver knees were located more posterior than those in in vivo after CR-TKA. From early flexion to high flexion, the medial and lateral contact points in cadaver knees were located more posterior than those in in vivo after CS-TKA.
Conclusions:
The axial rotation angle of cadaveric knees in the Oxford knee rig was similar to that measured in vivo after TKA. However, the anterior-posterior location of the femoral implant in cadaver knee was more posterior than that in in vivo knees after TKA.
