We developed three models of spasticity based on feedback from muscle states. The first model relied on feedback from muscle length and velocity. The second model relied on feedback from muscle length, velocity and acceleration. The third model relied on feedback from muscle force and its first time derivative (force rate). We first calibrated the models based on experimental data collected during passive stretches in children with cerebral palsy. We then used the calibrated models to predict the spastic response during gait. We showed that only the model based on feedback from muscle force and force rate could explain spastic muscle activity during passive stretches and gait. This suggests that force encoding in muscle spindles in combination with altered feedback gains and thresholds underlie activity of spastic muscles during passive stretches and gait.

This project contains experimental data and code necessary to reproduce all results presented in the associated publication. Please find more information in the manual (see folder Manual in simcpspasticity-code).