Effectiveness of Neuromodulation on Abductor Muscles Electrical Activity in Subjects With Low Back Pain: A Randomized, Controlled Crossover Trial

Introduction: Non-specific chronic low back pain (NSCLBP) is one of the main reasons of loss of function, that can have consequences such as job absenteeism and a decrease in the quality of life. Based in clinical findings and scientific studies, different risks factors have been stated as potential implication, such as muscles weakness and muscle tightness. Electromagnetic fields positively influence human tissue and have several therapeutic effects such as: pain relief, healing bone fracture, myorelaxation, myostimulation and joint mobilization. The aim of this study was to investigate whether the effect of a magnetic particle tape applied to the lumbar area in subjects with NSCLBP influences the strength of abductor muscle contraction and whether an immediate effect is obtained on surface electromyography (sEMG) of the Gluteus Medius and the Tensor of the Fascia Lata. Methods: It was carried out a double-blind, randomized, controlled, crossover trial and with test retest, with 41 consecutive patients younger than 65 years who previously diagnosed with NSCLBP to assess the effect of a tape with magnetic particles over hip abductor muscles strength and activity. Electromyographic (EMG) and force data were obtained during the Hip Stability Isometric Test (HipSIT). The HipSIT was used to assess the abduction strength using a hand-held dynamometer and electromyography (EMG). The HipSIT uses the maximum voluntary isometric contraction (MVIC). Four trials were recorded and the mean extracted for analysis. The tape was applied with either a magnetic particle tape or a sham magnetic particle tape bilaterally without tension on from L1 to L5 paravertebral muscles. Results: The significant increase in the recruitment of fibers and the significant increase in the maximum voluntary contraction by applying magnetic particle tape with respect to the placebo tape, correspond to the increases in the Peak Force and the decrease in the time to reach the maximum force (peak time) of both muscles. Conclusions: Application of a magnetic particle tape in people with low back pain suggest an increase in muscle strength of the Gluteus Medius and Tensor Fascia Lata bilaterally during the HipSIT test. Lumbar metameric neuromodulation with Magnetic Tape improves muscle activation of the hip musculature. Impact Statement The findings of this study will provide data on the effectiveness of a tape with magnetic particles for People with NSCLP for health care policy makers, physicians, and insurers. Data from this study will also inform future pragmatic trials for non-pharmacological interventions and chronic musculoskeletal pain conditions.