Abstract

Background

The prevalence of cerebral palsy (CP) is fairly high, ranging from 2 to 3 per 1000 live births. CP is a heterogeneous mix of disorders with a hallmark symptom of locomotor and postural-control deficits of varying severity due to brain injury.Conventional physical therapy (CPT), including neurodevelopmental treatment, partial weight support treadmill training, and strength training based on resistance exercises have been used broadly to improve balance and gait function. However, CPT is labor-intensive to therapists, increases the risk of falling, and lacks a sufficient repetition training to induce brain plasticity. To mitigate the inherent problems of CPT, a company recently developed Walkbot robotic-assisted gait training (RAGT) system for individuals with CP.

Objectives

Therefore, the present study has two purposes. The first one is to compare the effects of conventional gait training and Walkbot robot-assisted gait training on standing function, walking, running, jumping function, balance, gait speed, spasticity in patients with CP. The second is to determine the differences of the Walkbot RAGT group’s brain and muscle activation before and after the 18 sessions of intervention via electroencephalography (EEG) and electromyography (EMG).

Methods

We enrolled twenty children with CP (10 males and 10 females; mean age 15.95 ± 1.82 years) from a city hospital and rehabilitation center in South Korea. Ten children with CP completed 18 sessions (30 minutes per session) of RAGT plus CPT. Another ten individuals with CP underwent only 18 sessions of CPT. Outcome measures were assessed before and after the 18 sessions of each intervention. The clinical outcome instruments used in our study were Gross motor function measure (GMFM)-88, Pediatric balance scale (PBS), 10-meter waking test (10-MWT), and the Modified Tardieu Scale (MTS). Neurophysiological test were EEG frequency band power, activated EEG electrode location and topography, gait event-related spectral perturbations, and EMG on lower extremities. Analysis of covariance and Mann-Whitney U test were used to compare the RAGT and CPT groups and paired t-test, Wilcoxon signed-rank test was used to compare pre-test and post-test performance in each group.

Results

The self-selected velocity between pre-test and post-test in the CPT group showed significant change (p < 0.05) in the intragroup clinical test comparison.At the same time, other variables had no significant changes (p > 0.05). However,the RAGT group post-test had improved values on GMFM D, GMFM E, PBS, and the self-selected speed on 10-MWT (p < 0.05) compared to those in the pre-test.There were no significant effects related to the muscle response, angle of the Tardieu scale, and fast velocity in 10-MWT (p > 0.05).
GMFM E, PBS, and self-selected velocity in 10-MWT in the RAGT group presented better results than the CPT group (p < 0.05). GMFM D had a tendency for better outcomes in RAGT than the CPT group (p = 0.063). The modified Tardieu scale and fast velocity in 10-MWT had no significant difference between the two groups (p > 0.05).
Though no significant EEG band power data changes in the RAGT group were observed in the prefrontal area (Fp1, Fp2), supplementary motor area (FC1, FC2), left sensorimotor cortex (C1, C3), right sensorimotor cortex (C2, C4), and somatosensory association cortex (Cz, CP1, CP2, Pz) between the pre-test and post-test (p > 0.05), the low gamma (γ) band (25-40 Hz) on Cz had low tendency to change after the intervention (p = 0.095). However, there was a positive qualitative change shown in the gait cycle event-related spectral perturbation (ERSP) and topography.
The EMG analysis in the RAGT group showed a 12.8% increase of the left tibialis anterior muscle activation in comparison with the pre-test (p < 0.05). Nevertheless, muscle activation of the right tibialis anterior muscle and gastrocnemius medialis muscle had no statistical significances (p > 0.05)

Conclusions

Compared to the CPT group, Therefore, the Walkbot RAGT group was superior in standing and walking performance, balance parameters, and gait speed in self-selected conditions. Several research has been dedicated to the cortical activity during RAGT; however, this study utilized a novel experimental set up to measure the cortico-muscular contribution in RAGT in individual with CP. Though we did not find significant changes in the brain activities in RAGT, several activated brain area related locomotion existed in qualitative research. We did establish increased tibialis anterior muscle activation. It is important to note that the engagement of these activated cortical structures was not exactly equal to providing evidence for neuroplasticity. Further research is necessary to provide an in-depth interpretation of the cortico-muscular activities on the EEG signal and to compare neurophysiological assessment results with the CPT group.

Source :https://uml.yonsei.ac.kr/search/detail/CATTOT000002026715