Lumbopelvic rhythm

I’m trying to model asymmetry tasks with AnyBody software. It needs the portion of either lumbar or pelvis in the rotations of spine. How can I define lumbopelvic rhythm in asymmetry of trunk and extension tasks?
Is there any reference suggesting any value for this ratio?

Hi Mohadam,

Do you know the kinematics of the subject’s assymetric spine? If so you could look into the SpineFixationWithForceDepKinematics example - it shows how remove the prescribed spine rhythm and use drivers for each intervertebral joint in the lumbar spine. If you want to use the rhythm to drive the spine - you could check the current implementation of the spine rhythm and use something similar.

Please let us know which option is yours. The easiest way would probably be to implement some interpolation function driven joint angles and exclude the rhythm.

Best regards,