Real-time measurements of knee muscle moment arms during dynamic knee flexion-extension motion
McVeigh E, Blemker S
National Institutes of Health
The goal of this study was to evaluate the feasibility of measuring knee muscle moment arms over a full range of motion using real-time MRI in a 70cm bore Siemens Espree 1.5T scanner. Subjects flexed and extended their knees through a 140-degree range of motion at 8 cycles/minute. The images conveyed the complex path of the rectus femoris muscle, and moment arms estimated from the images compare well with literature values. This method can be applied to characterizing moment arms of other complex muscles under various loading conditions data that will greatly advance our understanding of in vivo muscle function.