Muscle forces calculation

[Yunus Rezvanifar]

Hi dear developers
I just watched your webinar on the great software

I may not be able to bring my subjects to a MOCAP lab and don't have any IMU equipments too,
so it occurred to me to get help from the SCONE to calculate muscle forces for simple daily activities of my subjects
so my question is that
1) Could the software estimate muscle forces same as inverse dynamic softwares?
2) Would the results corroborate experimental (e.g EMG ) results?

Best regards

[Thomas Geijtenbeek]

Hi Yunus,

SCONE is quite different from inverse dynamics software, because it uses forward dynamics to generate motion based on optimized controllers. In order to be able to do so, you need a task description and a neuromuscular controller that produces muscle excitation patterns. Whether the data corroborates experimental results depends on the motion, but in general it is pretty much open research. So far, walking and jumping are the tasks that have received the most attention.

[Yunus Rezvanifar]

You need a task description and a neuromuscular controller that produces muscle excitation patterns.

Thanks for the response

My target is to implement muscle forces on my femur FE model to do stress analysis and get other results.
1) I wanna know that if I recruit the proper task description and neuromuscular controller, would the estimated muscle forces be reliable and represent actual values?
2) How much is it possible for me as a biomechanics student to get the the settings done, cause as far as I know, control theory and optimization are two complex issues

I will appreciate any links or papers.

Best

[Thomas Geijtenbeek]

By femur FE model, do you mean Finite Element model? You need an OpenSim model to work with SCONE (https://opensim.stanford.edu/). These models use 'simple' hill-type muscles and rigid bodies.

[Yunus Rezvanifar]

Yes I mean femur finite element model.

I have my patient-specific OpenSim model.
I'm curious to know that if I get Scone to work with this patient-specific osim model would it estimate my patient's muscle forces correctly?
if yes, how can I validate it?

In this manner I would have muscle forces without limitation of accessibility of GAIT lab and MOCAP equipments or other devices.

[Thomas Geijtenbeek]

For validation of predictive simulations, you should compare the results to recorded kinematics, ground reaction force and EMG data.

Predictive simulations are not intended as replacement for motion capture, as the results can be quite different.

[Yunus Rezvanifar]

I got my answer, thank you Thomas.