A fair and EMG-validated comparison of recruitment criteria, musculotendon models and muscle coordination strategies, for the inverse-dynamics based optimization of muscle forces during gait.
Florian Michaud, Mario Lamas, Urbano Lugrís and 1 others
PMID 33509205WHAT IT FOUND
Simpler computer models predicted muscle forces during walking as accurately as complex physiological ones, while a synergy-based model produced unrealistically high joint forces.
The simplified approach was also much faster, offering no accuracy benefit from added complexity.
Key findings
01The simplest static optimization criterion achieved the highest correlation with experimental EMG data (mean r = 0.74) and was the fastest to compute (2.5 seconds per gait cycle).
02Adding physiological complexity to the musculotendon model did not significantly improve the accuracy of muscle activation predictions compared to static optimization.
03The synergy-based optimization approach produced joint reaction forces at the hip, knee, and ankle that were much higher than those estimated by other methods.
STILL TO COME
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study only included ten healthy subjects, so results may not apply to patients with pathological gait. Surface EMG cannot accurately measure deep muscles, limiting the validation of those specific muscle predictions. The synergy-based approach's high joint forces were not validated against actual in vivo measurements, only compared to other models.
Declared interests
Funded by Ministerio de Ciencia, Innovación y Universidades and Xunta de Galicia. No commercial conflicts declared.
The easy way to misread this
Do not assume that more complex physiological models provide more accurate muscle force estimates for standard gait analysis. This study found that simpler static optimization methods matched EMG data just as well, while the synergy-based method produced unrealistically high joint forces.