High tibia-femoral and patellar-femroal contact forces during squatting simulations


Hi Anybody,

I created a subject-specific knee model using the FDK method, according to the 5th challenge compitation data. I am trying to simualte the leg-suqatting and chair sit and rise gait cycles.
But the results of tibia-femoral and patellar-femroal contact forces are too high, about 3000N and 5000N, respectively.
And I am trying to adjust the ligaments (MCL LCL MPFL LPFL PCL …), but it seems doesn’t work. I think it may related to the patella tendon stiffness, my question is how to adjust the patella tendon stiffness in Anybody 6.0?


Dear Zhang,

Welcome to the forum.

I can see you have multiple post, the first time you post the administrator needs to approve the post, this is to avoid spam.

I assume that in the your current model the patella tendon is made using an AnykinPLine with a driver applied on providing a constant length?

If this is the case i would make this length driver a FDK dof secondly you will need to apply a stiffness function to this ligament in a similar was you did for the other ligaments though it needs to be much stiffer.

Honestly i do not think this it the solution to the high forces and usually this ligament is made as rigid.

I would look instead for a different calibration of your existing ligaments.

Best regards