A three-dimensional MRI analysis of knee kinematics

• Published in: Journal of orthopaedic research 2004-03, Vol.22 (2), p.283-292
• Main Authors: Patel, Vikas V, Hall, Katherine, Ries, Michael, Lotz, Jeff, Ozhinsky, Eugene, Lindsey, Colleen, Lu, Ying, Majumdar, Sharmila
• Format: Article
• Language: English
• Subjects: Biomechanical Phenomena; Biomechanics; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Kinematics; Knee joint; Knee Joint - physiology; Magnetic Resonance Imaging - instrumentation; Magnetic Resonance Imaging - methods; MRI; Observer Variation; Range of Motion, Articular - physiology; Reproducibility of Results
• ISSN: 0736-0266; 1554-527X
• DOI: 10.1016/j.orthres.2003.08.015

Purpose: To quantify normal, in vivo tibio-femoral knee joint kinematics in multiple weight bearing positions using non-invasive, high-resolution MRI and discuss the potential of developing future kinematic methods to assess patients with abnormal joint pathologies. Methods: Ten volunteers with clinically normal knees pushed inferiorly on the footplate of a weight bearing apparatus inside the MR scanner. The volunteers held the weight (133 N) for five scans as the knee motion was evaluated from 0° to 60° of flexion. Full extension was set as the zero point for all measured parameters. Using 3D reconstructions, tibia motion relative to the femur and flexion angle was measured as varus–valgus angle, axial rotation, anterior–posterior translation, and medial–lateral translation. Medial and lateral compartment tibio-femoral contact areas were examined and centroids of the contract areas were calculated. Results: Tibial internal rotation averaged 4.8° at 40° of flexion and then decreased. Tibial valgus increased by 8° at 60° of flexion. Femoral roll back also increased to 18.5 mm average at 60° of flexion, while the tibia translated medially 2.5 mm. Medial compartment femoro-tibial contact area started at 374 mm 2 and decreased to 308 mm 2 with flexion of 60°, while lateral compartment contact area did not change significantly from 276 mm 2. Conclusions: Results correlate with previous studies of knee kinematics while providing greater three-dimensional detail. MR imaging allows excellent non-invasive evaluation of knee joint kinematics with weight bearing. This tool may potentially be used for assessing knee kinematics in patients with knee pathology.