Joshua H. You

Effects of functional movement strength training on strength, muscle size, kinematics, and motor function in cerebral palsy: a 3-month follow-up.

We investigated the long-term effects of comprehensive hand repetitive intensive strengthening training (CHRIST) on strength, morphological muscle size, kinematics, and associated motor functional changes in children with cerebral palsy (CP). Ten children (5 boys, 5 girls; age range, 6-11 years, mean age, 8.6 years) participated in the study. The children were classified according to the Manual Ability Classification System: 5 were Level II, 2 were Level III, and 3 were Level IV. Quantitative biomechanical measurements were performed to determine muscle strength, muscle size, kinematics (normalized jerk score), and motor function using a dynamometer, ultrasound, Vicon motion analysis, and standardized clinical tests (Quality of Upper Extremity Skills Test, Jebsen-Taylor Hand Function Test, Functional Independence Measure, and Pediatric Motor Activity Log), respectively. Muscle strength, muscle size, kinematics, and motor function significantly improved after a 10-week intervention (3 times a week), and the long-term effects remained even at the 3-month follow-up. In conclusion, this is the first study highlighting the long-term efficacy of upper extremity strength training using the novel CHRIST system in children with CP, which will potentially open up new horizons for effective management in pediatric neurorehabilitation.

Effects of innovative virtual reality game and EMG biofeedback on neuromotor control in cerebral palsy

Sensorimotor control dysfunction or dyskinesia is a hallmark of neuromuscular impairment in children with cerebral palsy (CP), and is often implicated in reaching and grasping deficiencies due to a neuromuscular imbalance between the triceps and biceps. To mitigate such muscle imbalances, an innovative electromyography (EMG)-virtual reality (VR) biofeedback system were designed to provide accurate information about muscle activation and motivation. However, the clinical efficacy of this approach has not yet been determined in children with CP. The purpose of this study was to investigate the effectiveness of a combined EMG biofeedback and VR (EMG-VR biofeedback) intervention system to improve muscle imbalance between triceps and biceps during reaching movements in children with spastic CP. Raw EMG signals were recorded at a sampling rate of 1,000 Hz, band-pass filtered between 20-450 Hz, and notch-filtered at 60 Hz during elbow flexion and extension movements. EMG data were then processed using MyoResearch Master Edition 1.08 XP software. All participants underwent both interventions consisting of the EMG-VR biofeedback combination and EMG biofeedback alone. EMG analysis resulted in improved muscle activation in the underactive triceps while decreasing overactive or hypertonic biceps in the EMG-VR biofeedback compared with EMG biofeedback. The muscle imbalance ratio between the triceps and biceps was consistently improved. The present study is the first clinical trial to provide evidence for the additive benefits of VR intervention for enhancing the upper limb function of children with spastic CP.

Comprehensive Hand Repetitive Intensive Strengthening Training (CHRIST)-induced morphological changes in muscle size and associated motor improvement in a child with cerebral palsy: an experimenter-blind study.

PURPOSE This case study was conducted to determine Comprehensive Hand Repetitive Intensive Strengthening Training (CHRIST)-induced morphological changes in the commonly affected extensor carpi radialis (ECR) and triceps brachii (TRI) muscle and associated muscle strength and motor performance in a child with hemiparetic cerebral palsy (CP) using standardized clinical tests and ultrasound imaging. DESIGN A single case study with pre-/post-test. SUBJECT A 4.9-year-old female, diagnosed with hemiparetic CP. METHOD The child received a 5-week course of CHRIST course, comprising of 60-minute periods a day, five times a week. A real-time ultrasound imaging was performed to determine the CHRIST-induced changes in cross-sectional area (CSA) of the ECR and TRI. Clinical tests including the modified Wolf Motor function test (WMFT), the modified Jebsen-taylor hand function test (Jebsen hand) and the modified Pediatric Motor Activity Log (PMAL) questionnaire were used to compare the intervention-related changes in motor performance in upper extremity. RESULTS Ultrasound imaging data showed that the CSAs of both ECR and TRI muscles of the affected upper limb at relaxation and contraction states were enhanced and these therapy-induced morphological changes were associated with enhanced muscle strength and gross motor performance in reaching and grasping skills. CONCLUSIONS Our results suggest that the CHRIST is effective in treating muscle weakness and motor function in a child with hemiparetic CP. This is the first evidence in literature that might shed light on the therapeutic efficacy of our novel intervention on muscle size, associated muscle strength and motor improvement.

Novel augmented ADIM training using ultrasound imaging and electromyography in adults with core instability

OBJECTIVE To determine the effect of novel augmented abdominal drawing-in maneuver (ADIM) training using rehabilitative ultrasound imaging (RUSI) and electromyography (EMG) in adults with core instability. METHODS A convenience sample of 20 young adults with core instability (female =4; mean age ± standard deviation=24.4 ± 2.9 years) was recruited. Core instability was determined by the formal test. All subjects underwent an intensive ADIM that was augmented by comprehensive visual feedback via a pressure biofeedback unit, RUSI, and EMG. The intervention was provided for 20 minutes a day, 7 days a week, over a two-week period. RESULTS The paired t-test showed that both transverse abdominal (TrA) and internal oblique (IO) muscle thickness during ADIM were significantly greater than at rest (p= 0.000). However, external oblique (EO) muscle thickness remained relatively unchanged. The mean EMG amplitudes of the EO and erector spinae (ES) muscles were significantly decreased after the intervention (p=0.001, p=0.008). The intra-class correlation coefficient (ICC(1,2)) showed the excellent test-retest reliability for muscle thickness (ranging from 0.90 to 0.98 in the prone position). CONCLUSION This is the first evidence to demonstrate that the novel augmented ADIM training can effectively improve the lumbo-pelvic stabilization in adults with core instability.

Lumbopelvic Kinematic Characteristics of Golfers With Limited Hip Rotation

Background: While the biomechanical characteristics of the golf swing are well established, the lumbopelvic kinematic characteristics of professional golfers with limited hip internal rotation warrant further investigation. Purpose: The specific aim was to ascertain mechanical differences in lumbopelvic-hip movement of asymptomatic professional golfers with and without limited hip internal rotation during the golf swing. Study Design: Controlled laboratory study. Methods: Thirty professional male golfers (aged 25-35 years and 0 handicap matched) were classified into either the limited hip internal motion (LHIM) group (range of motion <20°) or the normal hip internal motion (NHIM) group (range of motion ≥30°). All participants underwent clinical tests (muscle strength, muscle length, and range of motion) and a biomechanical assessment using 8 infrared optic cameras in a motion analysis system. Independent t tests were performed to determine potential mean differences in muscle strength, length, and range of motion and lumbopelvic kinematics at P < .05. Results: Kinematic analysis revealed that the LHIM group showed significantly greater lumbar flexion (P < .001), right and left axial rotation (P < .025), and right-side lateral bending (P = .003) than the NHIM group. A greater pelvic posterior tilt was observed in the LHIM group when compared with the NHIM group (P = .021). Clinical tests showed reduced internal rotator muscle strength and shorter muscle length in the iliopsoas (P = .017) and hamstring (P < .001) among those in the LHIM group when compared with the NHIM group. Clinical Relevance: The study data suggest that constraints to hip joint internal rotation, along with muscle strength imbalances between the agonist and antagonist muscles and muscle tightness, are associated with substantially greater lumbopelvic movement during the golf swing.

A novel spinal kinematic analysis using X-ray imaging and vicon motion analysis: a case study.

This study highlights a novel spinal kinematic analysis method and the feasibility of X-ray imaging measurements to accurately assess thoracic spine motion. The advanced X-ray Nash-Moe method and analysis were used to compute the segmental range of motion in thoracic vertebra pedicles in vivo. This Nash-Moe X-ray imaging method was compared with a standardized method using the Vicon 3-dimensional motion capture system. Linear regression analysis showed an excellent and significant correlation between the two methods (R2 = 0.99, p < 0.05), suggesting that the analysis of spinal segmental range of motion using X-ray imaging measurements was accurate and comparable to the conventional 3-dimensional motion analysis system. Clinically, this novel finding is compelling evidence demonstrating that measurements with X-ray imaging are useful to accurately decipher pathological spinal alignment and movement impairments in idiopathic scoliosis (IS).

Intensive Abdominal Drawing-In Maneuver After Unipedal Postural Stability in Nonathletes With Core Instability

Context: The exact neuromechanical nature and relative contribution of the abdominal drawing-in maneuver (ADIM) to postural instability warrants further investigation in uninjured and injured populations. Objective: To determine the effects of the ADIM on static core and unipedal postural stability in nonathletes with core instability. Design: Controlled laboratory study. Setting: University research laboratory. Patients or Other Participants: A total of 19 nonathletes (4 women: age = 22.3 ± 1.3 years, height = 164.0 ± 1.7 cm, mass = 56.0 ± 4.6 kg; 15 men: age = 24.6 ± 2.8 years, height = 172.6 ± 4.7 cm, mass = 66.8 ± 7.6 kg) with core instability. Intervention(s): Participants received ADIM training with visual feedback 20 minutes each day for 7 days each week over a 2-week period. Main Outcome Measures(s): Core instability was determined using a prone formal test and measured by a pressure biofeedback unit. Unipedal postural stability was determined by measuring the center-of-pressure sway and associate...

Motor point location index using regression equations for the tibialis anterior muscle.

PURPOSE The present study highlighted a novel motor point location index (MPLI) for the precise localization of the motor point (MP) of the tibialis anterior (TA) using a regression equation. METHODS Twenty healthy young adults (female=8; mean age ± SD=18.50 ± 0.32) were volunteered for this study. The regression analysis was performed by correlating the MP locations with anatomical landmarks. The TA muscles MP location was bilaterally determined by needle electromyography (EMG) measurement. The anatomical landmarks included lower leg length (LLL), tibial tuberosity-intermalleolar line length (TT-ILL), the knee width (KW) and the leg width (LW). RESULTS The excellent correlation between the TT-ILL and the vertical MP location was obtained, R(2) 0.815. Approximately 82% of the variance of the vertical MP location was accounted for by its linear relationship with the TT-ILL. The high correlation between the LW and the horizontal MP location was observed, R(2)=0.764. Approximately 77% of the variance of the horizontal MP location index was accounted for by its linear relationship with the LW. CONCLUSIONS These findings indicate that the anatomical landmarks were useful to accurately predict MP locations for the TA muscle. Clinically, this MP location index using regression equations may be alternative for the current method that was not previously affordable.

Effects of dynamic neuromuscular stabilization on diaphragm movement, postural control, balance and gait performance in cerebral palsy

PURPOSE To determine the effects of a novel dynamic neuromuscular stabilization (DNS) technique on gross motor function, diaphragm movement, and activation of the external oblique (EO) and internal oblique (IO)/transversus abdominal (TrA) muscles in participants with cerebral palsy (CP). METHOD Fifteen participants with CP (7 females) underwent DNS intervention for 30 minutes/day, 3 days a week for 4 weeks. Gross motor function, diaphragm movement, and muscle activation were determined using a gross motor function measure (GMFM-88), ultrasound, and electromyography measurements, respectively, before and after the DNS core stabilization intervention. Paired t-tests were used at p < 0.05. DESIGN A single-arm, pretest-posttest clinical trial. RESULTS GMFM scores for standing, walking, and jumping domains were significantly improved after the intervention (P < 0.05). Diaphragm descending movement (P = 0.0001) and activation of the internal oblique and transversus abdominals were initially undetectable, but remarkably increased after the intervention (P = 0.012). CONCLUSIONS DNS is a promising, effective intervention for facilitating deep core muscle activation of the underactive muscle chain comprising the diaphragm, internal oblique, and transversus abdominals, thereby improving age-appropriate standing, walking, and jumping in participants with spastic diplegic CP.

The relationships between intra-abdominal echogenicity, cardiometabolic risk factors and physical performance in obese children

While the abdominal adipose tissue has been identified as an important pathomarker for the cardiometabolic syndrome in adults, the relationships between the cardiometabolic risk factors and abdominal adipose morphology or physical performance levels have not been examined in children with obesity. Therefore, the specific aim of this study was to investigate the relationships between risk factors (BMI and physical activity levels and abdominal fat layers including subcutaneous, intra-abdominal preperitoneal and mesenteric fat thickness in children with obesity. 30 children with obesity (mean ± SD = 10.0 ± 4.5 yrs; 9 girls; BMI > 20) underwent physical performance (curl-ups, sit and reach, push-ups, and a 400-m run), ultrasound measurement of thickness of fat composition of the abdomen, blood pressure, oxygen consumption. Pearson correlation analysis showed significant correlations, ranging from -0.523- 0.898 between the intra-abdominal adipose tissue thickness, cardiometabolic risk factors (BMI, blood pressure, heart rate), and the curl-up physical performance test. In conclusion, the present study provides a compelling evidence that the intra-abdominal adipose tissue morphological characteristics were associated with BMI, physical performance, and most importantly cardiometabolic risk factors (blood pressure and heart rate), which eventually contribute to the development of cardiometabolic syndrome in adulthood.