Deciphering Functional Connectivity Differences Between Motor Imagery and Execution of Target-Oriented Grasping.

This study aimed to delineate overlapping and distinctive functional connectivity in visual motor imagery, kinesthetic motor imagery, and motor execution of target-oriented grasping action of the right hand. Functional magnetic resonance imaging data were obtained from 18 right-handed healthy individuals during each condition. Seed-based connectivity and multi-voxel pattern analyses were employed after selecting seed regions with the left primary motor cortex and supplementary motor area. There was equivalent seed-based connectivity during the three conditions in the bilateral frontoparietal and temporal areas. When the seed region was the left primary motor cortex, increased connectivity was observed in the left cuneus and superior frontal area during visual and kinesthetic motor imageries, respectively, compared with that during motor execution. Multi-voxel pattern analyses revealed that each condition was differentiated by spatially distributed connectivity patterns of the left primary motor cortex within the right cerebellum VI, cerebellum crus II, and left lingual area. When the seed region was the left supplementary motor area, the connectivity patterns within the right putamen, thalamus, cerebellar areas IV-V, and left superior parietal lobule were significantly classified above chance level across the three conditions. The present findings improve our understanding of the spatial representation of functional connectivity and its specific patterns among motor imagery and motor execution. The strength and fine-grained connectivity patterns of the brain areas can discriminate between motor imagery and motor execution.

Trends in the Incidence and Etiology of Non-Traumatic Spinal Cord Injury in Korea: A Nationwide Population-Based Study From 2007 to 2020.

BACKGROUND: Although patients with non-traumatic spinal cord injury (NTSCI) have distinct epidemiological characteristics compared to those with traumatic spinal cord injury, no previous study has reported the incidence of NTSCI on a national scale in Korea. In this study, we examined the trend in incidence of NTSCI in Korea and described the epidemiological characteristics of patients with NTSCI using nationwide insurance data. METHODS: National Health Insurance Service data were reviewed for the period from 2007 to 2020. The International Classification of Diseases, 10th revision, was used to identify patients with NTSCI. Inpatients with newly diagnosed NTSCI on their first admission during the study period were included. Crude incidence was calculated using the annual number of NTSCI cases divided by the mid-year population estimates. Age-specific incidence was calculated by dividing the number of cases in 10-year age groups by the total number of individuals in that age group. Age-adjusted incidence was calculated using direct standardization. Annual percentage changes were calculated using Joinpoint regression analysis. The Cochrane-Armitage trend test was conducted to examine the trends of NTSCI incidence according to the types or etiologies of NTSCI. RESULTS: The age-adjusted incidence of NTSCI increased continuously from 24.11 per million in 2007 to 39.83 per million in 2020, with a significant annual percentage change (4.93%, P < 0.05). The age-specific incidence for those in their 70s and 80s or older was the highest and rapidly increased from 2007 to 2020. According to the types of paralysis in NTSCI, the proportion of tetraplegia decreased, whereas those of paraplegia and cauda equina increased significantly from 2007 to 2020. The proportion of degenerative diseases was the largest among all etiologies and increased significantly during the study period. CONCLUSION: The annual incidence of NTSCI in Korea is increasing significantly, particularly among older adults. As Korea is one of the countries with most rapidly aging population in the world, these results have significant implications, indicating that preventive strategies and sufficient rehabilitation medical services are warranted for the population of older adults.

Comparison of Trends in the Incidence of Traumatic Spinal Cord Injury in Daily Life, Automobile Accidents, and Industrial Accidents: A National Multi-Insurance Study in Korea.

BACKGROUND: To examine the incidence of traumatic spinal cord injury (TSCI) from all etiologies, we measured and compared the incidence of TSCI from three national or quasi-national databases in South Korea, namely, the National Health Insurance Service (NHIS), automobile insurance (AUI), and Industrial Accident Compensation Insurance (IACI). METHODS: We reviewed patients with TSCI reported in the NHIS database between 2009 and 2018, and in the AUI and IACI databases between 2014 and 2018. TSCI patients were defined as those first admitted to the hospital with a diagnosis of TSCI according to the International Classification of Diseases (10th revision) criteria. Age-adjusted incidence was calculated using direct standardization using the 2005 South Korean population or the 2000 US population as the standard population. The annual percentage changes (APC) of TSCI incidence were calculated. The Cochrane-Armitage trend test was performed according to the injured body region. RESULTS: In the NHIS database, age-adjusted TSCI incidence using the Korean standard population increased significantly from 2009 to 2018 (from 33.73 per million in 2009 to 38.14 per million in 2018, APC = 1.2%, P = 0.014). Contrarily, age-adjusted incidence in the AUI database significantly decreased from 13.88 per million in 2014 to 11.57 per million in 2018 (APC = - 5.1%, P = 0.009). In the IACI database, the age-adjusted incidence showed no significant difference, while crude incidence showed a significant increase (from 22.02 per million in 2014 to 28.92 per million in 2018, APC = 6.1%, P = 0.038). According to the age group, all the three databases showed high incidences of TSCI in those in their 60s and 70s or older. Among those in their 70s or older, the incidence of TSCI increased dramatically in the NHIS and IACI databases, while no significant trend was found in AUI database. In 2018, the number of TSCI patients was the highest among those over 70 years of age in the NHIS, whereas among those in their 50s were the highest in both AUI and IACI. The proportion of patients with cervical spinal cord injury was the most common in all these databases. CONCLUSIONS: The differences in trends in the incidence of TSCI may be due to the different etiologies and different characteristics of subjects depending on insurance type. These results imply the need for tailored medical strategies for the different injury mechanisms represented by three national insurance services in South Korea.

Vision-aided brain-machine interface training system for robotic arm control and clinical application on two patients with cervical spinal cord injury.

BACKGROUND: While spontaneous robotic arm control using motor imagery has been reported, most previous successful cases have used invasive approaches with advantages in spatial resolution. However, still many researchers continue to investigate methods for robotic arm control with noninvasive neural signal. Most of noninvasive control of robotic arm utilizes P300, steady state visually evoked potential, N2pc, and mental tasks differentiation. Even though these approaches demonstrated successful accuracy, they are limited in time efficiency and user intuition, and mostly require visual stimulation. Ultimately, velocity vector construction using electroencephalography activated by motion-related motor imagery can be considered as a substitution. In this study, a vision-aided brain-machine interface training system for robotic arm control is proposed and developed. METHODS: The proposed system uses a Microsoft Kinect to detect and estimates the 3D positions of the possible target objects. The predicted velocity vector for robot arm input is compensated using the artificial potential to follow an intended one among the possible targets. Two participants with cervical spinal cord injury trained with the system to explore its possible effects. RESULTS: In a situation with four possible targets, the proposed system significantly improved the distance error to the intended target compared to the unintended ones (p < 0.0001). Functional magnetic resonance imaging after five sessions of observation-based training with the developed system showed brain activation patterns with tendency of focusing to ipsilateral primary motor and sensory cortex, posterior parietal cortex, and contralateral cerebellum. However, shared control with blending parameter α less than 1 was not successful and success rate for touching an instructed target was less than the chance level (= 50%). CONCLUSIONS: The pilot clinical study utilizing the training system suggested potential beneficial effects in characterizing the brain activation patterns.

Oropharyngeal Dysphagia in Adults With Dyskinetic Cerebral Palsy and Cervical Dystonia: A Preliminary Study.

OBJECTIVES: To investigate the characteristics of oropharyngeal dysphagia in adults with dyskinetic cerebral palsy (DCP) and cervical dystonia (CD). DESIGN: Exploratory observational cross-sectional study. SETTING: University hospital. PARTICIPANTS: Seventeen patients with DCP (8 men, 9 women; age, 45.7±6.3y) enrolled in a randomized controlled trial on the effects of botulinum toxin injection on CD. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Baseline clinical assessments and videofluoroscopic swallowing studies (VFSSs) were conducted. VFSS findings were evaluated using the videofluoroscopic dysphagia scale (VDS) and the penetration-aspiration scale (PAS). The Gross Motor Function Classification System (GMFCS) and Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) scores were also assessed. Relationships between outcomes were evaluated using Spearman's rank correlation. RESULTS: The clinical assessment revealed abnormalities in chewing (n=10, 58.8%), tongue movement (n=10, 58.8%), and laryngeal elevation (n=8, 47.1%). The most common abnormality on the VDS was inadequate mastication (n=13, 76.5%), followed by premature bolus loss, vallecular residue, and penetration/aspiration (all: n=10, 58.8%). A maximum PAS score of 8 was observed in 8 of 17 patients (47.1%). Total and pharyngeal VDS scores were significantly correlated with TWSTRS scores (ρ=0.543, P=.024 and ρ=0.539, P=.026, respectively); the VDS oral score did not correlate with the TWSTRS score (ρ=0.446, P=.073). There was no significant correlation between VDS score and GMFCS level (ρ=0.212, P=.414). CONCLUSIONS: This preliminary observational study presents the characteristics of oropharyngeal dysphagia in adults with DCP and CD. Pharyngeal stage difficulties were negatively correlated with severity of CD, but not with GMFCS level. Screening for dysphagia may be recommended in adults with DCP and severe CD.

Dysphagia-Related Quality of Life in Adults with Cerebral Palsy on Full Oral Diet Without Enteral Nutrition.

There have been no quantitative studies on dysphagia and its impact on quality of life (QOL) of adults with cerebral palsy (CP). In this cross-sectional study, we aimed to investigate the characteristics of dysphagia symptoms and their impact on QOL in adults with CP on a full oral diet compared with healthy adults. Additionally, we aimed to determine the factors affecting dysphagia-related QOL in this population. We enrolled adults with CP on full oral diet (N = 117) and healthy individuals (N = 117) and interviewed them using the swallowing-quality of life (SWAL-QOL) questionnaire which includes 14 items regarding dysphagia symptoms and 30 items regarding swallowing-related QOL. The functional status of each participant with CP was evaluated using the gross motor function classification system, the manual ability classification system (MACS), and the Functional Oral Intake Scale (FOIS). Among pharyngeal symptoms, choking on food was reported most frequently (sometimes or more 76.9%), followed by coughing and choking on liquid. Among oral symptoms, chewing problems were reported most frequently (sometimes or more 59.8%), followed by food dribbling from the mouth (sometimes or more 53.8%). Compared to healthy adults, those with CP reported worse QOL across all SWAL-QOL items, with the lowest scores obtained for meal duration, followed by communication, burden, fatigue, sleep, and eating desire. On multiple linear regression analysis, higher MACS level, lower FOIS level, and older age were predictors of worse SWAL-QOL score. Among adults with CP, it is necessary to evaluate swallowing function and establish an active intervention plan even if a full oral diet is established.

Inertial Measurement Unit Based Upper Extremity Motion Characterization for Action Research Arm Test and Activities of Daily Living.

In practical rehabilitation robot development, it is imperative to pre-specify the critical workspace to prevent redundant structure. This study aimed to characterize the upper extremity motion during essential activities in daily living. An IMU-based wearable motion capture system was used to access arm movements. Ten healthy subjects performed the Action Research Arm Test (ARAT) and six pre-selected essential daily activities. The Euler angles of the major joints, and acceleration from wrist and hand sensors were acquired and analyzed. The size of the workspace for the ARAT was 0.53 (left-right) × 0.92 (front-back) × 0.89 (up-down) m for the dominant hand. For the daily activities, the workspace size was 0.71 × 0.70 × 0.86 m for the dominant hand, significantly larger than the non-dominant hand (p ≤ 0.011). The average range of motion (RoM) during ARAT was 109.15 ± 18.82° for elbow flexion/extension, 105.23 ± 5.38° for forearm supination/pronation, 91.99 ± 0.98° for shoulder internal/external rotation, and 82.90 ± 22.52° for wrist dorsiflexion/volarflexion, whereas the corresponding range for daily activities were 120.61 ± 23.64°, 128.09 ± 22.04°, 111.56 ± 31.88°, and 113.70 ± 18.26°. The shoulder joint was more abducted and extended during pinching compared to grasping posture (p < 0.001). Reaching from a grasping posture required approximately 70° elbow extension and 36° forearm supination from the initial position. The study results provide an important database for the workspace and RoM for essential arm movements.

A study on a robot arm driven by three-dimensional trajectories predicted from non-invasive neural signals.

BACKGROUND: A brain-machine interface (BMI) should be able to help people with disabilities by replacing their lost motor functions. To replace lost functions, robot arms have been developed that are controlled by invasive neural signals. Although invasive neural signals have a high spatial resolution, non-invasive neural signals are valuable because they provide an interface without surgery. Thus, various researchers have developed robot arms driven by non-invasive neural signals. However, robot arm control based on the imagined trajectory of a human hand can be more intuitive for patients. In this study, therefore, an integrated robot arm-gripper system (IRAGS) that is driven by three-dimensional (3D) hand trajectories predicted from non-invasive neural signals was developed and verified. METHODS: The IRAGS was developed by integrating a six-degree of freedom robot arm and adaptive robot gripper. The system was used to perform reaching and grasping motions for verification. The non-invasive neural signals, magnetoencephalography (MEG) and electroencephalography (EEG), were obtained to control the system. The 3D trajectories were predicted by multiple linear regressions. A target sphere was placed at the terminal point of the real trajectories, and the system was commanded to grasp the target at the terminal point of the predicted trajectories. RESULTS: The average correlation coefficient between the predicted and real trajectories in the MEG case was [Formula: see text] ([Formula: see text]). In the EEG case, it was [Formula: see text] ([Formula: see text]). The success rates in grasping the target plastic sphere were 18.75 and 7.50 % with MEG and EEG, respectively. The success rates of touching the target were 52.50 and 58.75 % respectively. CONCLUSIONS: A robot arm driven by 3D trajectories predicted from non-invasive neural signals was implemented, and reaching and grasping motions were performed. In most cases, the robot closely approached the target, but the success rate was not very high because the non-invasive neural signal is less accurate. However the success rate could be sufficiently improved for practical applications by using additional sensors. Robot arm control based on hand trajectories predicted from EEG would allow for portability, and the performance with EEG was comparable to that with MEG.

Smartwatch-based functional assessment for upper extremity impairment after musculoskeletal injuries: A pilot study.

Introduction: Wearable sensors are increasingly applied to rehabilitation for arm movement analysis. However, simple and clinically relevant applications are scarce. Objectives: To investigate the feasibility of single smart watch-based parameters for functional assessment in upper limb rehabilitation for musculoskeletal injuries using a commercial smart watch. Method: Ten patients with unilateral shoulder pain and range-of-motion limitations were enrolled. They wore Galaxy Watch® and performed three sets of upper extremity tasks consisting of gross activities-of-daily-living tasks, Wolf Motor Function Test (WMFT), and Upper Extremity Functional Index (UEFI), and the acceleration and angular velocities were acquired. The motion segment size (MSS), representing motion smoothness from a clinical perspective, and various sensor-based parameters were extracted. The correlation between the parameters and clinical outcome measures were analyzed. The percent relative range (PRR) of the significant parameters was also calculated. Results: For overhead and behind body activity task set, mean MSS for elbow flexion/extension axis significantly correlated with WMFT score (R = 0.784, p = .012). For planar tasks, mean MSS for the forearm supination/pronation (R = 0.815, p = .007) and shoulder rotation (R = 0.870, p = .002) axes significantly correlated with WMFT score. For forearm and fine movement task set, mean MSS of the elbow flexion/extension angle showed significant correlation with WMFT (R = 0.880, p < .001) and UEFI (R = 0.718, p = .019). The total performance time (R = -0.741, p = .014) also showed significant correlation with WMFT score. The PRR for mean MSS in forearm supination (71.5%, planar tasks) and mean MSS in x-direction (49.8%, forearm and fine motor movements) were similar to the PRR of WMFT (58.5%), suggesting sufficient variation range across different degree of impairments. Conclusion: The commercial smart watch-based parameters showed consistent potential for use in clinical functional assessments.

Reduction in limb-movement complexity at term-equivalent age is associated with motor developmental delay in very-preterm or very-low-birth-weight infants.

Reduced complexity during the writhing period can be crucial in the spontaneous movements of high-risk infants for neurologic impairment. This study aimed to verify the association between quantified complexity of upper and lower-limb movements at term-equivalent age and motor development in very-preterm or very-low-birth-weight infants. Video images of spontaneous movements at term-equivalent age were collected from very-preterm or very-low-birth-weight infants. A pretrained pose-estimation model and sample entropy (SE) quantified the complexity of the upper- and lower-limb movements. Motor development was evaluated at 9 months of corrected age using Bayley Scales of Infant and Toddler Development, Third Edition. The SE measures were compared between infants with and without motor developmental delay (MDD). Among 90 infants, 11 exhibited MDD. SE measures at most of the upper and lower limbs were significantly reduced in infants with MDD compared to those without MDD (p < 0.05). Composite scores in the motor domain showed significant positive correlations with SE measures at most upper and lower limbs (p < 0.05). The results show that limb-movement complexity at term-equivalent age is reduced in infants with MDD at 9 months of corrected age. SE of limb movements can be a potentially useful kinematic parameter to detect high-risk infants for MDD.

Effect of electrical stimulation on botulinum toxin a therapy in patients with chronic myofascial pain syndrome: a 16-week randomized double-blinded study.

OBJECTIVE: To evaluate the effect of different intensities of electrical stimulation on botulinum toxin A (BTX-A) injection at trigger points (TrPs) in patients with chronic myofascial pain syndrome (MPS). DESIGN: Double-blind randomized trial. SETTING: Outpatient rehabilitation clinic. PARTICIPANTS: Patients (N=76) with chronic MPS of the neck and shoulder regions. INTERVENTIONS: Patients were randomly assigned to 1 of 2 intervention groups: BTX-A injection followed by (1) electrical stimulation that induces visible muscle contraction (MOTOR group); or (2) electrical stimulation with an intensity just above the sensory threshold (SENSORY group). Electrical stimulation was administered for 30 minutes a day for 3 consecutive days after injection. MAIN OUTCOME MEASURES: The primary outcome was the visual analog scale (VAS) for pain. Secondary outcomes included the Neck Pain and Disability Scale (NPAD), Global Assessment of Improvement Scale (GAS), and pressure pain threshold (PPT). RESULTS: The VAS scores decreased significantly at 4, 8, 12, and 16 weeks from the baseline in both groups. Significant changes in the NPAD score over time were noted only in the SENSORY group at 8, 12, and 16 weeks. The SENSORY group showed lower VAS and NPAD scores at 16 weeks (P=.043 and P=.041, respectively), and higher treatment success rates at 12 and 16 weeks (P=.039 and P=.024, respectively) than the MOTOR group. There was no significant result in the GAS and PPT. CONCLUSIONS: Short-term electrical stimulation may affect the reduction in pain after BTX-A injection at TrPs in patients with chronic MPS of the neck and shoulder regions. Based on the results, it seems that sensory electrical stimulation was superior to motor electrical stimulation as an adjuvant therapy to BTX-A injection in patients with chronic MPS. Further studies are warranted to investigate the method facilitating the effect of BTX-A on MPS.

Functional recovery after injury of motor cortex in rats: effects of rehabilitation and stem cell transplantation in a traumatic brain injury model of cortical resection.

PURPOSE: Experimental studies and clinical trials designed to help patients recover from various brain injuries, such as stroke or trauma, have been attempted. Rehabilitation has shown reliable, positive clinical outcome in patients with various brain injuries. Transplantation of exogenous neural stem cells (NSCs) to repair the injured brain is a potential tool to help patient recovery. METHODS: This study aimed to evaluate the therapeutic efficacy of a combination therapy consisting of rehabilitation and NSC transplantation compared to using only one modality. A model of motor cortex resection in rats was used to create brain injury in order to obtain consistent and prolonged functional deficits. The therapeutic results were evaluated using three methods during an 8-week period with a behavioral test, motor-evoked potential (MEP) measurement, and measurement of the degree of endogenous NSC production. RESULTS: All three treatment groups showed the effects of treatment in the behavioral test, although the NSC transplantation alone group (CN) exhibited slightly worse results than the rehabilitation alone group (CR) or the combination therapy group (CNR). The latency on MEP was shortened to a similar extent in all three groups compared to the untreated group (CO). However, the enhancement of endogenous NSC proliferation was dramatically reduced in the CN group compared not only to the CR and CNR groups but also to the CO group. The CR and CNR groups seemed to prolong the duration of endogenous NSC proliferation compared to the untreated group. CONCLUSIONS: A combination of rehabilitation and NSC transplantation appears to induce treatment outcomes that are similar to rehabilitation alone. Further studies are needed to evaluate the electrophysiological outcome of recovery and the possible effect of prolonging endogenous NSC proliferation in response to NSC transplantation and rehabilitation.

Epidemiology of Work-Related Traumatic Spinal Cord Injury: An Analysis of Workers' Compensation Claims in Korea, 2011-2019.

OBJECTIVE: We aimed to identify the incidence and burden of work-related traumatic spinal cord injury (wrTSCI) in Korea in the 10-year period from 2010 to 2019. METHODS: We used nationwide workers' compensation insurance data. The study population comprised industrially injured workers with TSCI diagnosis codes. The annual incidence of wrTSCI (number per million workers) was calculated. RESULTS: The mean annual incidence of wrTSCI was 22.8/1,000,000 (95% confidence interval, 20.5 to 25.0), and the mean total cost per claim was 231.40 million KRW. The incidence of TSCI in the cervical region was the highest (13.1/1,000,000; 95% confidence interval, 11.4 to 14.9), and most cases were in the construction industry (47.3%). CONCLUSION: These findings can help identify specific at-risk groups and facilitate the development of prevention strategies.

Spinal Cord Injury Fact Sheet in Korea.

Spinal cord injury (SCI) has been recognized as a medically complex and life-disrupting condition. As the aging of the population accelerates, the trend of SCI has changed. This review aimed to provide comprehensive statistics and recent epidemiological changes in SCI and rehabilitation in Korea. All three insurance databases (National Health Insurance Service [NHIS], automobile insurance [AUI], and industrial accident compensation insurance [IACI]) were considered. These nationwide databases provide data on the current trends in term of incidence, etiology, and rehabilitation of SCI. Traumatic spinal cord injury (TSCI) was more frequent among the elderly in the NHIS compared to working age individuals in the AUI and IACI. In all three trauma-related insurance databases, male with TSCI outnumbered female. TSCI incidence per year was approximately 17 times higher among males than females, on average, in IACI. In all three insurances, the cervical level of TSCI was the most frequent. Although the ratio of SCI patients receiving rehabilitation treatment at primary and secondary hospitals increased for nine years, the increase in training on activities of daily living (ADL training) was found to be relatively small. This review provides a broader and comprehensive understanding of the incidence, etiology, and rehabilitation treatment of SCI in Korea.

Impact of Cerebellar Injury on Neurodevelopmental Outcomes in Preterm Infants With Cerebral Palsy.

OBJECTIVE: We aimed to analyze brain imaging findings and neurodevelopmental outcomes of preterm infants diagnosed with cerebral palsy. DESIGN: Brain magnetic resonance imaging of preterm infants born between 23 and 32 wks' gestation and diagnosed with cerebral palsy at 2 yrs of corrected age were evaluated. Brain lesions were categorized as periventricular leukomalacia, intraventricular hemorrhage, and cerebellar hemorrhage and graded by the severity. Neurodevelopmental outcomes were assessed using the Bayley Scales of Infant and Toddler Development, Third Edition, at 18-24 mos corrected age, and the Korean Ages and Stages Questionnaire at 18 and 24 mos of corrected age. RESULTS: Cerebral palsy was found in 38 children (6.1%) among 618 survivors. Cerebellar injury of high-grade cerebellar hemorrhage and/or atrophy accounted for 25%. Among patients with supratentorial lesions, those having cerebellar injury showed significantly lower scores on each Korean Ages and Stages Questionnaire domain except gross motor than patients without cerebellar injury. They also revealed a high proportion of patients below the cutoff value of Korean Ages and Stages Questionnaire in language, fine motor, and problem-solving domains ( P < 0.05) and lower Bayley Scales of Infant and Toddler Development, Third Edition, language composite scores ( P = 0.038). CONCLUSIONS: Poor neurodevelopmental outcomes other than motor function were associated with cerebellar injury. Evaluation of the cerebellum may help predict functional outcomes of patients with cerebral palsy.

Six-minute walking distance reference value for healthy Indonesian children: A cross-sectional study from the largest country in South East Asia.

Introduction: There is no global reference value for the 6-minute walking distance (6MWD) in paediatric populations, as it can vary greatly depending on local characteristics and anthropometric measures. This study aimed to identify a 6MWD reference value that could be applied in both local and regional settings. Method: This cross-sectional multicentre study investigated a healthy paediatric population aged 4-18 years in Indonesia. The 6-minute walk test (6MWT) was conducted in accordance with the American Thoracic Society guidelines. Data were presented as the 6MWD according to age and sex per year. Univariate and multivariate analyses were conducted on the basis of the 6MWDpred Rizky formula. Results: A total of 634 participants were included in this study. Age, sex, weight, leg length and height affected the 6MWD (P<0.001). In the regression model, sex and height were the predictors of 6MWD, with height as the best single predictor. Conclusion: The reference charts and 6MWDpred Rizky formula are applicable in multi-ethnic paediatric Indonesian populations but in limited settings.

Rehabilitation outcome in people with spinal cord injuries resulting from diving in South Korea.

STUDY DESIGN: Retrospective electronic medical record review combined with a telephone interview. OBJECTIVES: The purpose of this study was to describe the neurological and socio-professional outcomes of patients with diving injuries of the cervical spine. SETTING: A tertiary hospital and its affiliated rehabilitation hospital in South Korea. METHODS: Electronic medical records were reviewed for medical and neurological information. Telephone interviews were then conducted with questionnaire regarding specific circumstances at the time of injury and social status. RESULTS: A total of 33 patients with spinal cord injury (SCI) due to diving accidents were analyzed, of which 27 responded to telephone interviews. Thirty-two (97%) participants were men and 27 (81.8%) were younger than 40 years at the time of injury. The American Spinal Injury Association grade A was the most common of all grades in 16 participants (48.5%), whereas C4 was the most common neurologic level of the injury (n = 13, 39.4%). SCI due to diving accidents most commonly occurred in swimming pools in holiday lodges (n = 12, 36.4%). Five out of 13 married couples with motor complete SCI were divorced or separated after injury. Eight persons resumed work or studies after the injury, with a mean return time of 33 (24.4) months. CONCLUSIONS: SCI resulting from a diving accident not only causes severe functional impairment but can also result in changes in marital and employment status. This study may be used as a basic source of education and awareness to prevent further SCI due to diving accidents.

Gene Expression Profile Changes in the Stimulated Rat Brain Cortex After Repetitive Transcranial Magnetic Stimulation.

Repetitive transcranial magnetic stimulation (rTMS) is gaining popularity as a research tool in neuroscience; however, little is known about its molecular mechanisms of action. The present study aimed to investigate the rTMS-induced transcriptomic changes; we performed microarray messenger RNA, micro RNA, and integrated analyses to explore these molecular events. Eight adult male Sprague-Dawley rats were subjected to a single session of unilateral rTMS at 1 Hz (n = 4) or sham (n = 4). The left hemisphere was stimulated for 20 minutes. To evaluate the cumulative effect of rTMS, eight additional rats were assigned to the 1-Hz (n = 4) or sham (n = 4) rTMS groups. The left hemisphere was stimulated for 5 consecutive days using the same protocol. Microarray analysis revealed differentially expressed genes in the rat cortex after rTMS treatment. The overrepresented gene ontology categories included the positive regulation of axon extension, axonogenesis, intracellular transport, and synaptic plasticity after repeated sessions of rTMS. A single session of rTMS primarily induced changes in the early genes, and several miRNAs were significantly related to the mRNAs. Future studies are required to validate the functional significance of selected genes and refine the therapeutic use of rTMS.

Exploring user perspectives on a robotic arm with brain-machine interface: A qualitative focus group study.

Brain-machine Interface (BMI) is a system that translates neuronal data into an output variable to control external devices such as a robotic arm. A robotic arm can be used as an assistive living device for individuals with tetraplegia. To reflect users' needs in the development process of the BMI robotic arm, our team followed an interactive approach to system development, human-centered design, and Human Activity Assistive Technology model. This study aims to explore the perspectives of people with tetraplegia about activities they want to participate in, their opinions, and the usability of the BMI robotic arm. Eight people with tetraplegia participated in a focus group interview in a semistructured interview format. A general inductive analysis method was used to analyze the qualitative data. The 3 overarching themes that emerged from this analysis were: 1) activities, 2) acceptance, and 3) usability. Activities that the users wanted to do using the robotic arm were categorized into the following 5 activity domains: activities of daily living (ADL), instrumental ADL, health management, education, and leisure. Participants provided their opinions on the needs and acceptance of the BMI technology. Participants answered usability and expected standards of the BMI robotic arm within 7 categories such as accuracy, setup, cost, etc. Participants with tetraplegia have a strong interest in the robotic arm and BMI technology to restore their mobility and independence. Creating BMI features appropriate to users' needs, such as safety and high accuracy, will be the key to acceptance. These findings from the perspectives of potential users should be taken into account when developing the BMI robotic arm.