What are my muscles up to? The contribution of surface electromyography to clinical decision-making

Muscles move the body. The varying levels of movement precision needed daily results from a complex interplay within the central nervous system, muscles and sensory feedback, referred to as neuromechanics. This neuromechanical interplay is often impaired in pathology. Although, diagnosis and therapy would benefit from information about the patient's specific neuromechanical control, no procedures have yet been established in clinical practice that allow this information to be fully recorded. Surface electromyography (sEMG) links neuronal input and muscle function and helps to understand how the CNS orchestrates the multitude of possibilities the neuromusculoskeletal system has at its disposal to solve a movement task. This 2024 Basmajian-Lecture-Paper will highlight sEMG applications in physiological and pathological conditions, to illustrate the potential contribution of sEMG to clinical decision-making. Focussing first on infants' motor development, it will contribute to the discussion on how neuromechanics and motor skills develop. Continuing with considerations on motor unit activation in health and disease and describing the difference between physiological and pathological muscle coordination in dynamic conditions, it aims to address the possibilities but also the limitations of sEMG in clinical applications. Finally, the influence of robotic support on neuromechanical control and thus on re-learning of motor skills are discussed.