Quantification of patellar tracking using kinematic MRI
Article first published online: 17 NOV 2005
Copyright © 1998 Wiley-Liss, Inc., A Wiley Company
Journal of Magnetic Resonance Imaging
Volume 8, Issue 3, pages 724–732, May/June 1998
How to Cite
Powers, C. M., Shellock, F. G. and Pfaff, M. (1998), Quantification of patellar tracking using kinematic MRI. J. Magn. Reson. Imaging, 8: 724–732. doi: 10.1002/jmri.1880080332
- Issue published online: 17 NOV 2005
- Article first published online: 17 NOV 2005
- Manuscript Accepted: 3 NOV 1997
- Manuscript Revised: 19 SEP 1997
- Manuscript Received: 24 JUN 1997
- Foundation for Physical Therapy Inc.
- Patellofemoral joint;
- Patellar tracking
The purpose of this study was to describe a method to quantify dynamic patellar tracking using kinematic MRI (KMRI). Twelve normal females and three patients with patellofemoral pain participated. Imaging was performed with a 1.5-T/64-MHz MR system using a fast spoiled gradient-recalled acquisition in the steady state (GRASS) pulse sequence. A nonferromagnetic positioning device permitted active, bilateral knee extension against resistance (15% bwt) from 45° knee flexion to full extension. Subjects were instructed to extend their knees at a rate of 9° per second, which allowed images to be obtained at 45°, 36°, 27°, 18°, 9°, and 0°. All images were assessed for medial/lateral patellar displacement, patellar tilt, and sulcus angle using a computer-aided system. Normal patellar motion was characterized by medial movement from 45° to 18°, followed by a reversal toward lateral displacement from 18° to full extension. The results for patellar tilt revealed a tendency toward decreasing lateral tilt as the knee extended. Sulcus angle measurements indicated that the patella was moving to a more shallow portion of the trochlear groove (superiorly) during extension.