Comparing the Lower-Limb Muscle Activation Patterns of Simulated Walking Using an End-Effector-Type Robot with Real Level and Stair Walking in Children with Spastic Bilateral Cerebral Palsy.

Cerebral palsy is a neurologic disorder caused by lesions on an immature brain, often resulting in spasticity and gait abnormality. This study aimed to compare the muscle activation patterns of real level and stair walking with those of simulated walking using an end-effector-type robot in children with spastic cerebral palsy. The electromyographic activities of the vastus lateralis, biceps femoris, tibialis anterior and medial gastrocnemius of nine children with spastic bilateral cerebral palsy were measured during gait using a wireless surface EMG device. Morning walk was used for the simulated gait. Differences in the muscle activation patterns between the real and simulated gait conditions were analyzed. In the loading response, all four muscles showed reduced activity during two simulated conditions. In mid-stance, mGCM showed reduced activity during simulated conditions, whereas BFem showed greater activity during simulated level walking. In the swing phase, BFem and TAnt activity was reduced during the simulated conditions. The onset-offset of the VLat, BFem and TAnt activity was significantly delayed during simulated versus real level walking. No differences in activity onset-offset were observed between the simulated level and stair conditions. In conclusion, the robot-simulated gait showed differences in its muscle activation patterns compared with the real gait conditions, which must be considered for gait training using an end-effector-type robot.

Virtual reality rehabilitation in children with brain injury: a randomized controlled trial.

AIM: To investigate the efficacy of a virtual reality rehabilitation system of wearable multi-inertial sensors to improve upper-limb function in children with brain injury. METHOD: Eighty children (39 males, 41 females) with brain injury including cerebral palsy aged 3 to 16 years (mean age 5y 8mo, SD 2y 10mo) were assessed as part of a multicentre, single-blind, randomized controlled trial. The intervention group received a 30-minute virtual reality intervention and a 30-minute session of conventional occupational therapy while the control group received 60 minutes of conventional occupational therapy per session, with 20 sessions over 4 weeks. The virtual reality rehabilitation system consisted of games promoting wrist and forearm articular movements using wearable inertial sensors. The Melbourne Assessment of Unilateral Upper Limb Function-2 (MA-2), Upper Limb Physician's Rating Scale, Pediatric Evaluation of Disability Inventory Computer Adaptive Test, and computerized three-dimensional motion analysis were performed. RESULTS: Both groups (virtual reality, n=40; control, n=38) significantly improved after treatment compared to baseline; however, the virtual reality group showed more significant improvements in upper-limb dexterity functions (MA-2, virtual reality group: Δ=10.09±10.50; control: Δ=3.65±6.92), performance of activities of daily living, and forearm supination by kinematic analysis (p<0.05). In the virtual reality group, children with more severe motor impairment showed significant improvements compared to those with less severe impairment. INTERPRETATION: The virtual reality rehabilitation system used in this study, which consists of wearable inertial sensors and offers intensive, interactive, and repetitive motor training, is effective in children with brain injury. WHAT THIS PAPER ADDS: Both virtual reality rehabilitation and conventional occupational therapy were effective for upper-limb training. Virtual reality training was superior in improving dexterity, performance of activities of daily living, and active forearm supination motion. The effect of virtual reality training was significant in children with more severe motor impairments.

Relationship between the more-affected upper limb function and daily activity performance in children with cerebral palsy: a cross-sectional study.

BACKGROUND: There are differences in roles between the more-affected and less-affected upper limb of children with cerebral palsy (CP). However, there is a lack of studies of the relationship between the more-affected limb function and activities of daily living (ADL) in children with CP. Thus, the aim of this prospective cross-sectional study was to investigate the relationship between more-affected upper limb function and ADL in children with CP. METHODS: Children with spastic CP (unilateral CP n = 28, bilateral CP n = 31; 34 males, 25 females; mean age ± SD, 6.8 ± 3.1y [range, 3-14y]) participated in this study. Function of the more-affected upper limb was measured using the Melbourne Assessment of Unilateral Upper limb Function, version 2 (MA2) and the Upper Limb Physician's Rating Scale (ULPRS). Performance of daily living activities was measured using the Pediatric Evaluation of Disability Inventory-Computer Adaptive Test (PEDI-CAT). RESULTS: The range, accuracy and fluency dimension of MA2 and ULPRS total scores were moderately correlated with the daily activity domain (r = 0.47, 0.47, 0.56 for MA2 and r = 0.50 for ULPRS, respectively; P < 0.001) rather than the mobility, social/cognitive, and responsibility domains of the PEDI-CAT. ULPRS scores for elbow extension, supination in extension, supination in flexion, and two-handed function were moderately correlated with the PEDI-CAT daily activity domain (r = 0.44, 0.43, 0.41, and 0.49, respectively; P < 0.01). Finger opening and thumb-in-palm deformity of the ULPRS did not correlate with any PEDI-CAT domain. CONCLUSIONS: The MA2 range, accuracy, and fluency domains (rather than dexterity) had the strongest correlations with the PEDI-CAT daily activity domain. Elbow extension, forearm supination, and two-handed function (rather than wrist and finger movements) of the ULPRS had the strongest correlations with the PEDI-CAT daily activity domain.

Overground Robot-Assisted Gait Training for Pediatric Cerebral Palsy.

The untethered exoskeletal robot provides patients with the freest and realistic walking experience by assisting them based on their intended movement. However, few previous studies have reported the effect of robot-assisted gait training (RAGT) using wearable exoskeleton in children with cerebral palsy (CP). This pilot study evaluated the effect of overground RAGT using an untethered torque-assisted exoskeletal wearable robot for children with CP. Three children with bilateral spastic CP were recruited. The robot generates assistive torques according to gait phases automatically detected by force sensors: flexion torque during the swing phase and extension torque during the stance phase at hip and knee joints. The overground RAGT was conducted for 17~20 sessions (60 min per session) in each child. The evaluation was performed without wearing a robot before and after the training to measure (1) the motor functions using the gross motor function measure and the pediatric balance scale and (2) the gait performance using instrumented gait analysis, the 6-min walk test, and oxygen consumption measurement. All three participants showed improvement in gross motor function measure after training. Spatiotemporal parameters of gait analysis improved in participant P1 (9-year-old girl, GMFCS II) and participant P2 (13-year-old boy, GMFCS III). In addition, they walked faster and farther with lower oxygen consumption during the 6-min walk test after the training. Although participant P3 (16-year-old girl, GMFCS IV) needed the continuous help of a therapist for stepping at baseline, she was able to walk with the platform walker independently after the training. Overground RAGT using a torque-assisted exoskeletal wearable robot seems to be promising for improving gross motor function, walking speed, gait endurance, and gait efficiency in children with CP. In addition, it was safe and feasible even for children with severe motor impairment (GMFCS IV).

Home-based virtual reality-enhanced upper limb training system in children with brain injury: a randomized controlled trial.

Background: Rehabilitation of upper limb function can be challenging in children with brain lesion. Recent virtual reality (VR) rehabilitation may be an additional treatment option in pediatric rehabilitation. Objectives: To assess the feasibility and effectiveness of a home-based VR-enhanced rehabilitation program with wearable multi-inertial measurement unit (IMU) sensors on upper limb functions in children with brain injury. Methods: This multicenter single blind randomized controlled trial included 40 children with cerebral palsy (CP) or static brain injury. Subjects were randomized 1:1 to experimental and control group. Both the groups maintained the same therapeutic content and dose of occupational therapy during the intervention period. The experimental group performed additional training at home using the VR-enhanced program for at least 30 min/day, 5 days/week, for 6 weeks. VR training consisted of daily activities or games promoting wrist and forearm articular movements using wearable IMU sensors. The Melbourne Assessment of Unilateral Upper Limb Function-version 2 (MA2), Upper Limb Physician's Rating Scale (ULPRS), Pediatric Evaluation of Disability Inventory-computer adaptive test (PEDI-CAT), computerized 3D motion analysis, and user satisfaction survey were performed. Mann-Whitney U test was used to compare treatment effects between groups, and Friedman and Wilcoxon signed-rank tests were used to compare pre and post intervention. Results: Overall 35 children (15 in VR group and 20 in control group) completed the protocol. In the experimental group, an average VR training time was 855 min. The accuracy of motion measured by MA2, segmental movements by ULPRS, daily living capability and social cognitive function by PEDI-CAT, movement time and shoulder movement pattern by motion analysis showed significant improvements. However, there were no significant differences in any of the functional outcome measures compared to the control group. All the children and parents reported positive experiences. Conclusions: Home-based VR training though it had limited impact on improving upper limb function, it could help improve social cognitive function, movement pattern, and efficiency in children with brain injury and could be an effective means of extending clinical therapy to the home. Clinical Trial Registration: CRIS.nih.go.kr: identifier KCT0003172.

The Effects of Wearing Facemasks during Vigorous Exercise in the Aspect of Cardiopulmonary Response, In-Mask Environment, and Subject Discomfort.

Non-pharmaceutical intervention such as wearing a mask during the pandemic of SARS-CoV-2 is one of the most important ways to prevent the spread of the virus. However, despite high effectiveness and easy to access, the biggest problem is 'discomfort'. The purpose of this study was to measure the changes of cardiopulmonary response and related factors affecting breathing discomfort when wearing a mask during vigorous exercise. Fifteen healthy male adults participated in this study. The experimental protocol consisted of three conditions: no mask; KF-94 mask; and sports mask. Each condition consisted of three stages: stage I, 2 m/s on even level; stage II, 2 m/s with 5° inclination; and stage III, 3 m/s on even level. Oxygen saturation (SaO2) and heart rate (HR), partial pressure of carbon dioxide (pCO2), energy expenditure index (EEI), in-mask temperature, humidity, and a five-point scale questionnaire to evaluate subjective discomfort were measured. The results show that there was a significantly higher discomfort score in mask conditions compared with no mask (p < 0.05) and only pCO2 change significantly related to subjective discomfort during exercise (p < 0.05). Moreover, the pCO2 washout was significantly disturbed when wearing a sports mask in stages 2 and 3, which was related to wearer subjective discomfort.

Analysis of foot kinematics during toe walking in able-bodied individuals using the Oxford Foot Model.

Various neurological and musculoskeletal disorders can induce pathologic toe walking and lead to changes in foot kinematics. In this study, we analyzed the differences in foot kinematics between toe walking and heel-toe walking (HW) in able-bodied individuals. Twenty young healthy adults performed three gaits: HW, comfortable-height toe walking (CTW), and maximum-height toe walking (MTW). Oxford Foot Model was used for gait analysis. Toe walking showed increase of forefoot plantarflexion and hindfoot internal rotation compared to HW. Thus, our results may help distinguish the pathologic mechanism of the equinus gait in various disorders from the kinematic change of toe walking itself.

Gait Adaptation Is Different between the Affected and Unaffected Legs in Children with Spastic Hemiplegic Cerebral Palsy While Walking on a Changing Slope.

Walking on sloped surfaces requires additional effort; how individuals with spastic hemiplegic cerebral palsy (CP) manage their gait on slopes remains unknown. Herein, we analyzed the difference in gait adaptation between the affected and unaffected legs according to changes in the incline by measuring spatiotemporal and kinematic data in children with spastic hemiplegic CP. Seventeen children underwent instrumented three-dimensional gait analysis on a dynamic pitch treadmill at an incline of +10° to -10° (intervals of 5°). While the step length of the affected legs increased during uphill gait and decreased during downhill gait, the unaffected legs showed no significance. During uphill gait, the hip, knee, and ankle joints of the affected and unaffected legs showed increased flexion, while the unaffected leg showed increased knee flexion throughout most of the stance phase compared with the affected leg. During downhill gait, hip and knee flexion increased in the affected leg, and knee flexion increased in the unaffected leg during the early swing phase. However, the ankle plantar flexion increased during the stance phase only in the unaffected leg. Although alterations in temporospatial variables and joint kinematics occurred in both legs as the slope angle changed, they showed different adaptation mechanisms.

Spatiotemporal parameters from instrumented motion analysis represent clinical measurement of upper limb function in children with cerebral palsy.

BACKGROUND: There are various tools that measure upper limb function in children with cerebral palsy(CP) clinically, but these measurement methods are examiner-dependent and scale values are not proportional to the upper limb function which makes it difficult to quantify the function. RESEARCH QUESTION: The purpose of this study was to investigate whether the new parameters derived from 3D motion analysis reflect the upper limb function which measured by Melbourne Assessment 2 (MA2) in children with cerebral palsy (CP) compared to the clinical measurements. METHODS: Forty children with CP (24 boys, 16 girls; mean [SD] age, 6 years 11 months [3 years 5 months]) were recruited. Motion capture was conducted during phases T1-T4 of Reach and Grasp Cycles. New parameters (movement time, number of movement units, index of curvature) were derived from wrist marker data. Range of motion (ROM), accuracy, dexterity, and fluency of unilateral upper limb function were assessed using MA2. Spearman rank coefficients were determined to evaluate correlations between MA2 and the new parameters. RESULTS AND SIGNIFICANCE: Index of curvature correlated negatively with MA2 accuracy scores during T1 (rs -0.347, p < 0.05), T2 (rs -0.471, p < 0.01), and T3 (rs -0.660, p < 0.01). Number of movement units correlated negatively with MA2 ROM, accuracy, and fluency scores during T1 (ROM rs -0.334; accuracy rs -0.331; fluency rs -0.375; p < 0.05) and T3 (ROM rs -0.499; accuracy rs -0.531; fluency rs -0.515; p < 0.01). Index of curvature and number of movement units are objective, simple parameters showing fair to good correlation with MA2 accuracy and fluency of upper limb function.

Evaluation of sitting and standing postural balance in cerebral palsy by center-of-pressure measurement using force plates: comparison with clinical measurements.

BACKGROUND: Center-of-pressure (CoP) measurements have been studied for assessing balance control. While CoP measurements using force plates have been used to assess standing balance in children with cerebral palsy (CP), it has not been assessed in a sitting position, which specifically reflects trunk postural control. RESEARCH QUESTION: The purpose of this study was to compare CoP measurements using force plates during both standing and sitting trials with the Pediatric Balance Scale (PBS) in children with spastic CP. METHODS: We recruited 26 children with spastic CP (7.8 ±â€¯3.4 years, 4-13 years) and used the PBS, a validated evaluation tool that measures static and dynamic balance control. We took CoP measurements using force plates during sitting and standing. For both trials, subjects stayed still for 10 s with their eyes open or closed. We calculated the CoP velocity, mediolateral (ML) and anteroposterior (AP) velocity, and ML and AP displacements of CoP. RESULTS AND SIGNIFICANCE: During standing trials, static PBS standing scores negatively correlated with more AP displacement and velocity than ML displacement and velocity (p < 0.05). During sitting trials, dynamic PBS sitting scores negatively correlated with ML displacement and velocity (p < 0.05). CoP parameters in the ML direction of the sitting position and CoP parameters in the AP direction of the standing position may better reflect the balance control in children with spastic CP.

Paralysis of the gastrocnemius medial head differentially affects gait patterns and muscle activity during level and stair ascent locomotion.

BACKGROUND: Prior studies have analyzed the activity of the gastrocnemius (GCM) medial and lateral heads as a single unit because it is technically challenging to separately analyze the function of each component in vivo. However, functional variation between the medial and lateral heads is expected due to their anatomical differences. RESEARCH QUESTION: What is the independent function of the medial GCM? How does paralysis of the GCM medial head affect gait kinematics?. METHODS: Twelve healthy adults (two males and ten females; age: 28.2 [±7.72] years) that were scheduled to undergo neurolysis of the tibial nerve branch supplying the medial head of the GCM for aesthetic calf reduction participated in the study. Gait analysis was performed using a computerized opto-electric gait analysis system to measure kinematic data. Surface electromyography (EMG) was recorded simultaneously during the gait analysis. Surface electrodes were placed on seven muscles. Pre-procedure and 1-week and 3-month post-procedure data were compared using a linear mixed model. RESULTS: During level walking, decreased activity of the GCM medial head did not significantly change gait kinematics. However, a significant increase in GCM lateral head and hamstring activities occurred after a branch nerve block to the GCM medial head. During stair ascent, in contrast to level walking, changes in EMG activity only occurred in the GCM medial head, and post-procedure ankle dorsiflexion angles at the end of the terminal-stance phase significantly increased. Ankle plantarflexion angles during the push-off phase were also decreased when compared with pre-procedure values. SIGNIFICANCE: The human body response to dysfunction of the GCM medial head depended on the type of locomotion.