Evaluation of electrically elicited antagonist coactivation strategies. I. Isometric contractions

Generally, applications of functional electrical stimulation to paralyzed limbs have involved the agonist prime mover without much emphasis on the role of the antagonist musculature. However, the need for anatomic stabilization of joints by antagonist muscles has been extensively documented throughout the physiology literature. In this study, the authors assessed the signal tracking capability and torque transmission efficiency of several coactivation strategies elicited by means of electrical stimulation under isometric conditions using ramp and sinusoidal inputs. The results indicate that a strategy with 25 to 50% overlap as well as 0 to 10% antagonist gain will help maintain joint integrity during prolonged use of FES.