Seeking Assistance: Elderly Musculoskeletal Models and Motions

[Silas Purja]

Hi,

I hope this message finds you well. I am currently in search of musculoskeletal models and motions specifically designed for elderly individuals. Despite checking the model libraries, I have been unable to locate suitable resources.

Could you kindly provide guidance or direct me to the appropriate sources to find these models?

Your assistance is greatly appreciated.

Many thanks,
Silas

[Nicos Haralabidis]

Hello Silas,

Perhaps this article by Thelen (2003) [1] can help inform you how to modify the muscle model parameters - https://asmedigitalcollection.asme.org/ ... HzLiUckJDv

[1] Adjustment of Muscle Mechanics Model Parameters to Simulate Dynamic Contractions in Older Adults

Thanks,

Nicos

[John Davis]

You might consider using the Arnold 2010 model - it uses muscle parameters from Ward 2008 which used 21 cadavers that were ~82 years. The Arnold model uses a specific tension of 61 N/cm^2 (higher than what's typically estimated from direct measurements of muscles) to scale PCSA to max isometric force, partly to counteract the possible muscle atrophy seen in elderly subjects, so you might want to "undo" that choice and scale down muscle strength. The Arnold 2010 paper has a nice discussion on page 272 about the choice of PCSA as it relates muscle loss in the elderly - though Arnold et al. were aiming to use their model for healthy adults.

The Arnold model runs more slowly than its "descendents" like the Rajagopal 2016 model, mostly because the Arnold model uses a lot of elliptical wrapping surfaces. But that's really only an issue for static optimization or CMC, and on a modern computer I don't think it would even be that bad.