Normative EMG activation patterns of school-age children during gait

Abstract

Gait analysis is widely used in clinics to study walking abnormalities for surgery planning, definition of rehabilitation protocols, and objective evaluation of clinical outcomes. Surface electromyography allows the study of muscle activity non-invasively and the evaluation of the timing of muscle activation during movement. The aim of this study was to present a normative dataset of muscle activation patterns obtained from a large number of strides in a population of 100 healthy children aged 6-11 years. The activity of Tibialis Anterior, Lateral head of Gastrocnemius, Vastus Medialis, Rectus Femoris and Lateral Hamstrings on both lower limbs was analyzed during a 2.5-min walk at free speed. More than 120 consecutive strides were analyzed for each child, resulting in approximately 28,000 strides. Onset and offset instants were reported for each observed muscle. The analysis of a high number of strides for each participant allowed us to obtain the most recurrent patterns of activation during gait, demonstrating that a subject uses a specific muscle with different activation modalities even in the same walk. The knowledge of the various activation patterns and of their statistics will be of help in clinical gait analysis and will serve as reference in the design of future gait studies.

Multiple gait patterns within the same Winters class in children with hemiplegic cerebral palsy

“…More specifically, a single subject's muscle does not show a single "preferred" pattern of activation, but up to 4-5 distinct EMG patterns, each characterized by a different number of activation intervals occurring within the gait cycle (Agostini et al, 2010;Di Nardo et al, 2013). This was demonstrated on a sample of 100 typically developing children (Agostini et al, 2010). Similar findings were obtained, by other researchers, in healthy adults (Di Nardo et al, 2013), indicating that "ensemble averaging" over different EMG activation modalities is not appropriate.…”

“…More specifically, a single subject's muscle does not show a single "preferred" pattern of activation, but up to 4-5 distinct EMG patterns, each characterized by a different number of activation intervals occurring within the gait cycle (Agostini et al, 2010;Di Nardo et al, 2013). This was demonstrated on a sample of 100 typically developing children (Agostini et al, 2010).…”

“…This holds especially for the muscles directly involved in the ankle joint movements. These findings suggested us that the EMG signal must be averaged across cycles belonging to the same foot-floor contact class (Agostini et al, 2010(Agostini et al, , 2014c.…”

Instrumented Gait Analysis for an Objective Pre-/Postassessment of Tap Test in Normal Pressure Hydrocephalus

“…[22][23][24][25][26] Three footswitches were fixed under the heel and the first and fifth metatarsal heads of each foot sole ( fig 1A), and a knee goniometer was attached to the lateral side of each leg ( fig 1B). Subjects were instructed to walk barefoot at a self-selected speed.…”

“…16 Recent advances in gait analysis highlight the importance of evaluating uninterrupted walking trials lasting 2 to 3 minutes. [22][23][24][25][26] This allows for a reliable evaluation of gait parameters because 50 to 150 gait cycles are collected and analyzed for each patient.…”