Fully automatic extraction of knee kinematics from dynamic CT imaging; normative tibiofemoral and patellofemoral kinematics of 100 healthy volunteers

• Published in: The knee 2023-03, Vol.41, p.9-17
• Main Authors: Dunning, Hans, van de Groes, S.A.W., Buckens, C.F., Prokop, Mathias, Verdonschot, Nico, Janssen, Dennis
• Format: Article
• Language: English
• Subjects: 4DCT; Biomechanical Phenomena; Dynamic Imaging; Femur - diagnostic imaging; Healthy Volunteers; Humans; Knee; Knee Joint - diagnostic imaging; Knee kinematics; Patellofemoral joint; Range of Motion, Articular; Tibia - diagnostic imaging; Tibiofemoral joint; Tomography, X-Ray Computed
• ISSN: 0968-0160; 1873-5800
• DOI: 10.1016/j.knee.2022.12.011

Accurate assessment of knee kinematics is important in the diagnosis and quantification of knee disorders and to determine the effect of orthopaedic interventions. Despite previous studies showing the usefulness of dynamic imaging and providing valuable insights in knee kinematics, dynamic imaging is not widely used in clinics due to a variety of causes. In this study normative knee kinematics of 100 healthy subjects is established using a fully automatic workflow feasible for use in the clinic. One-hundred volunteers were recruited and a dynamic CT scan was made during a flexion extension movement. Image data was automatically segmented and dynamic and static images were superimposed using image registration. Coordinate systems for the femur, patella and tibia were automatically calculated as well as their dynamic position and orientation. Dynamic CT scans weremade withan effective radiation dose of 0.08 mSv. The median tibial internal rotation was 4° and valgus rotation is 5° at full flexion. Femoral rollback of the lateral condyle was 7 mm versus 2 mm of the medial condyle. The median patella flexion reached 65% of tibiofemoral flexion and the median tilt and rotation were 5° and 0° at full flexion, respectively. The median mediolateral translation of the patella was 3 mm (medially) in the first 30° of flexion. The current study presents TF and PF kinematic data of 97 healthy individuals, providing a unique dataset of normative knee kinematics. The short scanning time, simple motion and, automatic analysis make the methods presented suitable for daily clinical practice.