Figure 3.

(A and B) Relative activation of the transferred BR muscle and (C and D) absolute lateral pinch force (in Newtons) predicted by simulations incorporating non-impaired, and patient-specific strength, based on the muscle co-activation patterns recorded from each patient (3 trials for four of five patients, and 2 trials for the final patient; 14 trials in total). A) Non-impaired strength enabled maximum BR activation for co-activation patterns measured from four of five individuals studied, but zero activation for the fifth (p5), leading to C) relatively consistent pinch force magnitudes for all but one individual, whose co-activation patterns generated a net flexion moment even without activation of the transferred BR. B) Patient-specific strength increased variability in BR activation, and thus D) pinch force magnitudes across subjects. M_flex indicates co-activation patterns which could not support BR activation without generating a net elbow flexion moment, and thus entirely passive lateral pinch forces. All of the results presented here are for the “resting” tensioning condition.