Synergistic laser and haptic therapy for pain relief and muscle relaxation of forearm flexors

Abstract

—In the realm of pain relief and therapy treatment, traditional single modality treatment approaches do not suffice in offering meaningful and long-lasting therapeutic effects. A modified treatment method with the laser and haptic activations within a single, hand-held device to enhance the synergistic effect during treatment is designed. It has been established that a laser, either red or infrared, is effective for promoting collagen synthesis and healing wounds by utilizing light to alter chemical and structural components at the cellular level. Alternatively, muscles are made to relax and blood flow is enhanced by apt haptic stimulation of blood circulation through proper placement of the inducing electrode. The combination therapy device merges these modalities into a ‘therapy gun’ that proves to be very effective. Though the comprehensive study and effect of the entire musculature is very cumbersome, we have focused on the most commonly used muscle groups, the flexor muscles of the forearm. The results are tested and validated using multiple biosignal study including electromyography (EMG) and endodermal activity (EDA) and the muscle load activities manipulated from the EMG. The intensity and time of treatment shall be changed depending on the patient's requirements. Post-treatment, following therapy, the EMG results showed a marked reduction in muscle activation, with an MVC of 1.350 ​mV and a decrease in RMS values, reflecting muscle relaxation. The PSD of the EMG signal shifted towards lower frequencies, confirming reduced muscle activity. Similarly, post-treatment EDA results demonstrated a decrease in skin conductance, with values stabilizing around 4.976 ​S, reflecting a return to baseline levels of physiological arousal. The histogram and PSD of the EDA signal showed a shift towards lower frequencies, consistent with the calming effects of the vibration therapy.