Added Value of Dynamic EMG in the Assessment of the Equinus and the Equinovarus Foot Deviation in Stroke Patients and Barriers Limiting Its Usage

Abstract

Equinus (EFD) and equinovarus foot deviation (EVFD) are the most frequent lower limb deformities in stroke survivors. The equinus component can be triggered by a combination of dorsiflexor deficits, plantar flexor overactivity, muscle stiffness, and contractures. The varus component is typically due to an imbalance between invertor and evertor muscle actions. An improvement in identifying its causes leads to a more targeted treatment. These deformities are typically assessed via a thorough clinical evaluation including the assessment of range of motions, force, spasticity, pain, and observational gait analysis. Diagnostic nerve blocks are also being increasingly used. An advantage of dynamic electromyography (dEMG) is the possibility of measuring muscle activity, overactivity or lack thereof, during specific movements, e.g., activity of both ankle plantar flexors and dorsiflexors during the swing phase of gait. Moreover, fine-wire electrodes can be used to measure the activity of deep muscles, e.g., the tibialis posterior. An impediment to systematic use of dEMG in the assessment of EFD and EVFD, as a complimentary tool to the clinical evaluation, is a lack of evidence of its usefulness. Unfortunately, there are few studies found in literature. In order to fill this void, we studied three pairs of patients suffering from chronic hemiparesis consequent to a stroke, with EFD or EVFD. At the initial evaluation they all displayed the same clinical traits, very similar walking patterns, and an overlapping gait kinematics. However, the patterns of muscle activity differed considerably. dEMG data acquired during walking provided information that was not available from the sole clinical assessment. The contribution of this information to the subsequent clinical and rehabilitation process was discusses along with the barriers that limit the use of dEMG as a routine tool in neurorehabilitation.

Fundamental Concepts of Bipolar and High-Density Surface EMG Understanding and Teaching for Clinical, Occupational, and Sport Applications: Origin, Detection, and Main Errors

“…In neurorehabilitation, the use of motion analysis with sEMG clearly influences treatment planning in multiple patient populations and can lead to better outcomes when properly used [57]. Gait analysis is a functional evaluation that provides a quantification of the observed performance and identifies motor deficits and the underlying causes of the observed pathological patterns [58][59][60]. This evaluation allows for the formulation of a precise and targeted therapeutic plan, such as surgical, pharmacological, orthotics or physiotherapy plans [57,58,[61][62][63][64].…”

Respective Contributions of Instrumented 3D Gait Analysis Data and Tibial Motor Nerve Block on Presurgical Spastic Equinus Foot Assessment: A Retrospective Study of 40 Adults

“…The poor predictive value of TA EMG activation during the swing phase was previously shown by Burridge et al in a cohort of 112 patients, among whom more than 50% had a limitation in dorsiflexion speed despite TA activation without triceps surae overactivity ( 23 ). In our study, this could be explained by either spastic myopathy, overactivity of plantar flexor muscles not evaluated by dynamic EMG (lateral gastrocnemius, tibialis posterior, fibularis longus), or by the lack of activation of accessory levators (extensor digitorum longus and extensor pollicis longus) ( 24 ). In any event, this indicates the need for further studies to analyze a possible modification in TA activation pattern before and after MNB or even to compare the envelopes of EMG signals.…”

Electrode Size and Placement for Surface EMG Bipolar Detection from the Brachioradialis Muscle: A Scoping Review

“…As it is possible to obtain reliable sEMG acquisition for clinical applications, and this provide valuable information that can improve the treatment appropriateness [165][166][167][168], we strongly encourage professionals to follow the guidelines, especially when the signal is used to make clinical decisions, such as when planning neuro-orthopedic surgery or focal muscle inhibitions [169]. The smaller the cross-sectional area of the muscles of interest (e.g., forearm muscles, children's muscles), the more rigor must be used.…”

“…We believe that the detection and interpretation of sEMG signal should be taught at the academic level, as is done for other biosignals (e.g., ECG and EEG), and that international protocols should be developed and approved to reduce this barrier to the widespread clinical use of sEMG. As outlined in the recent literature, there is an urgent need for better education of healthcare personnel in sEMG and other medical technologies [152,153,163,167].…”