Knee Joint Center from Joint Reactions Analysis

[Spencer Wangerin]

Hello,

I am using gait data from subject GIL06 from the "Multiple Speeds Walking Simulations" to run a Joint Reactions Analysis. My goal is to obtain a total joint contact force/moment system for the right knee joint to apply as loads in a finite element simulation. I have read throughout the OpenSIM User's Manual and in other sources that the reaction loads act at the joint center of both the parent and child bodies. However, I haven't been able to confirm the joint center's coordinates or true location relative to either the femur or tibia.

Does the true joint center coincide with the tibial segment reference frame (at the midpoint between the femoral epicondyles)? If not, how do I determine its location?

Thank you very much for your help.
Spencer

[jimmy d]

Hi Spencer,
Yes, the joint center coincides with the tibial reference frame. You can check these in the GUI by examining the a parameters of the bodies and joint.
cheers,
james