Comparison of Agonist vs. Antagonist Stimulation on Triceps Surae Spasticity in Spinal Cord

Abstract

Objectives:One of the most common and disabling complications that affects individuals with spinal cord injury is spasticity. The purpose of this study is to compare the effect of agonist and antagonist electrical stimulations on triceps surae muscle spasticity in patients with spinal cord injury. Methods:A total of 30 subjects with spinal cord injury were considered for the study. They were divided into two groups randomly. Group 1 received agonist electrical stimulation (stimulation of triceps surae) and group 2 received antagonist electrical stimulation (stimulation of tibialis anterior) for 20 min, once daily, and 5 days per week for two weeks. To evaluate the therapeutic effect, modified Ashworth score, deep tendon reflex score and clonus score were tested before and after the treatment. Post treatment evaluation was made 24 h after the last treatment session.Results: Both the groups showed significant reductions in the modified Ashworth scores and deep tendon reflex scores after the intervention, but these reductions were not found in the clonus score. Also, there was no significant difference in the post intervention scores of modified Ashworth scale, deep tendon reflex and clonus score between the two groups.Discussion: This study provides evidence that both agonist electrical stimulation and antagonist electrical stimulations are equally effective in reducing spasticity in triceps surae muscle in patients with spinal cord injury.

Antagonist Versus Agonist Muscle Neuromuscular Electrical Stimulation on Spasticity in Stroke Patients

“…The neurophysiologic rationale for the effectiveness of neuromuscular electrical stimulation to the antagonist muscle seems to rest on the principle of "reciprocal inhibition" [19,20].As neuromuscular electrical stimulation is applied to the antagonist muscle, the large diameter Ia muscle spindle afferent fibers originating in the muscle are exited. The action potentials generated in these fibers are transmitted to the spinal cord and excite the spinal interneurons, which intern inhibit the activity in the motor neurons to the spastic muscles.…”

Neurophysiological and clinical outcome measures of the impact of electrical stimulation on spasticity in spinal cord injury: Systematic review and meta-analysis

“…It should be considered that, due to the nature of noninvasive ES as an intervention, it was noted by most assessed studies that blinding the participant and the therapist who administered the intervention was not possible. For some studies, one assessor was blinded and others were not (34,47).…”

“…Only 11 studies included information on whether participants were permitted to continue taking anti-spasticity medication (34,37,40,42,43,(45)(46)(47)(60)(61)(62). In one of these 11 studies, taking anti-spasticity medication was an exclusion criteria (47), whilst the 10 other studies allowed participants to continue taking their medication.…”

“…From this systematic review, 5 of 6 studies using TENS, which obtained statistically significant improvements in spasticity, used 99 or 100 Hz (29-31, 33, 37), and the other used 30 Hz (34). Of the remaining 4 studies which used TENS [excluding Vodovnik.…”