EMG activity in gait: The influence of motor disorders

Abstract

EMG techniques have been widely used in research and clinical settings, revealing underlying mechanisms that are involved in pathology and assisting clinicians to decision-making. Current findings based on EMG, combined with kinematic and kinetic data during gait, describe very specific activation patterns and muscle synergies in people with and without motor disorders, which contribute to the understanding of the disease's causes and to build more accurate and detailed simulation models. Furthermore, the EMG findings during stance and swing phase are discussed and more particularly the co-activation of the agonist and antagonist muscles. This helps to comprehend the contribution of certain muscles/ muscle groups when power generation or stability is required and the effect of spasticity and stretch reflex on the movement quality. This chapter also supplies the reader with several examples that reveal, by means of EMG assessments, mechanisms of the neuromuscular system to compensate primary or secondary causes of movement disorders. Finally, the limitations and difficulties in EMG interpretation in pathological cases are discussed.