Relieving effect of TENS on painful muscle contraction produced by an impairment of reciprocal innervation: an electrophysiological analysis.
A young female outpatient experienced painful tonic contractions in the right triceps surae muscles as a result of a partial damage of the right peroneal nerve. Electrophysiological recordings of the soleus muscle showed a tonic EMG activity and an hyperexcitability of the monosynaptic H reflex (Hmax/Mmax ratio: 90%). Application of transcutaneous electrical nerve stimulation (TENS, 1-2 min) on the peroneal nerve trunk at the head of the fibula resulted both in a pain relief and in the disappearance of the tonic activity in the muscles supplied by the antagonist nerve. Simultaneously, the Hmax/Mmax ratio decreased to normal values (49%). This was followed by an after-effect lasting more than 30 min. The potential role of an impairment of reciprocal inhibition in the originating mechanism of these troubles is discussed.
Wilier
Jean Claude
JC
Laboratory of Clinical Neurophysiology, Faculty of Medicine Saint-Antoine, 75571 Paris Cedex 12 France.
D000293:Adolescent; D004599:Electric Stimulation Therapy; D004576:Electromyography; D004594:Electrophysiology; D005260:Female; D006801:Humans; D009119:Muscle Contraction; D010543:Peroneal Nerve / Q000293:injuries* / Q000503:physiopathology; D004561:Transcutaneous Electric Nerve Stimulation