Cortical neuromodulation by constraint-induced movement therapy in congenital hemiparesis: an FMRI study

Robot-assisted gait training improves walking and cerebral connectivity in children with unilateral cerebral palsy

BACKGROUND

Robot-assisted gait training (RAGT) is promising to help walking rehabilitation in cerebral palsy, but training-induced neuroplastic effects have little been investigated.

METHODS

Forty unilateral cerebral palsy children aged 4-18 years were randomly allocated in a monocentric study to ten 20-minute RAGT sessions with the G-EO system, five days a week (n = 20) or to a control group (who continued conventional care with six 30-minute physiotherapy sessions, three days a week) (n = 20), two weeks running, from September 2020 to December 2021. Clinical and MRI outcomes were compared before and one month after therapy. The primary outcome was gait speed. Secondary outcomes were a 6-minute walking test distance, Gross Motor Function Measure-88 (GMFM-88) dimensions D and E, Patient Global Impression of Improvement, resting-state functional connectivity within the sensorimotor network, and structural connectivity in the corticospinal tracts.

RESULTS

Gait speed and the 6-minute walking test distance improved more after RAGT. Resting-state functional connectivity increased after RAGT but decreased in controls between superior and lateral healthy or lateral injured sensorimotor networks. GMFM-88 and structural connectivity in corticospinal tracts were unchanged. Impression of improvement in children was better after RAGT.

CONCLUSION

Short-term benefit of repetitive RAGT on walking abilities and functional cerebral connectivity was found in unilateral cerebral palsy children.

IMPACT STATEMENT

Short-term repetitive robot-assisted gait training improves gait speed and walking resistance and increases cerebral functional connectivity in unilateral cerebral palsy. GMFM dimensions D and E were unchanged after short-term repetitive robot-assisted gait training in unilateral cerebral palsy.

A Review of Current Perspectives on Motoric Insufficiency Rehabilitation following Pediatric Stroke

Pediatric stroke (PS) is an injury caused by the occlusion or rupture of a blood vessel in the central nervous system (CNS) of children, before or after birth. Hemiparesis is the most common motoric deficit associated with PS in children. Therefore, it is important to emphasize that PS is a significant challenge for rehabilitation, especially since the consequences may also appear during the child's growth and development, reducing functional capacity. The plasticity of the child's CNS is an important predecessor of recovery, but disruption of the neural network, specific to an immature brain, can have harmful and potentially devastating consequences. In this review, we summarize the complexity of the consequences associated with PS and the possibilities and role of modern rehabilitation. An analysis of the current literature reveals that Constraint-Induced Movement Therapy, forced-use therapy, repetitive transcranial magnetic stimulation, functional electrical stimulation and robot-assisted therapy have demonstrated at least partial improvements in motor domains related to hemiparesis or hemiplegia caused by PS, but they are supported with different levels of evidence. Due to the lack of randomized controlled studies, the optimal rehabilitation treatment is still debatable, and therefore, most recommendations are primarily based on expert consensuses, opinions and an insufficient level of evidence.

Cortical hemodynamic response and networks in children with cerebral palsy during upper limb bilateral motor training

Understanding the characteristics of functional brain activity is important for motor rehabilitation of children with cerebral palsy (CP). Using the functional near-infrared spectroscopy (fNIRS) technology, the cortical response and networks of prefrontal (PFC) and motor cortices (MC) were analyzed for children with CP and typical development (CTD). Compared with CTD, the resting cortical response of dominant MC in children with CP increased, and the functional connectivity between cerebral areas decreased. In the motor state of children with CP, the coupling strength started from dominant MC increased compared with resting state, and the hemispherical autonomy index (HAI) of the dominant MC was higher than that in the CTD, which reflected the leading role of dominant MC in brain regulation during motor. The functional connectivity between bilateral MC was positively correlated with motor performance. This study provided effective indices for evaluating the motor function and real-time impact of motor on brain networks.

Somatosensory Plasticity in Hemiplegic Cerebral Palsy Following Constraint Induced Movement Therapy

BACKGROUND

Children with hemiplegic cerebral palsy (HCP) experience upper limb somatosensory and motor deficits. Although constraint-induced movement therapy (CIMT) improves motor function, its impact on somatosensory function remains underinvestigated.

OBJECTIVE

The objective of this study was to evaluate somatosensory perception and related brain responses in children with HCP, before and after a somatosensory enhanced CIMT protocol, as measured using clinical sensory and motor assessments and magnetoencephalography.

METHODS

Children with HCP attended a somatosensory enhanced CIMT camp. Clinical somatosensory (tactile registration, 2-point discrimination, stereognosis, proprioception, kinesthesia) and motor outcomes (Quality of Upper Extremity Skills [QUEST] Total/Grasp, Jebsen-Taylor Hand Function Test, grip strength, Assisting Hand Assessment), as well as latency and amplitude of magnetoencephalography somatosensory evoked fields (SEF), were assessed before and after the CIMT camp with paired sample t-tests or Wilcoxon signed-rank tests.

RESULTS

Twelve children with HCP (mean age: 7.5 years, standard deviation: 2.4) participated. Significant improvements in tactile registration for the affected (hemiplegic) hand (Z = 2.39, P = 0.02) were observed in addition to statistically and clinically significant improvements in QUEST total (t = 3.24, P = 0.007), QUEST grasp (t = 3.24, P = 0.007), Assisting Hand Assessment (Z = 2.25, P = 0.03), and Jebsen-Taylor Hand Function Test (t = -2.62, P = 0.03). A significant increase in the SEF peak amplitude was also found in the affected hand 100 ms after stimulus onset (t = -2.22, P = 0.04).

CONCLUSIONS

Improvements in somatosensory clinical function and neural processing in the affected primary somatosensory cortex in children with HCP were observed after a somatosensory enhanced CIMT program. Further investigation is warranted to continue to evaluate the effectiveness of a sensory enhanced CIMT program in larger samples and controlled study designs.

Perinatal stroke: mapping and modulating developmental plasticity

Most cases of hemiparetic cerebral palsy are caused by perinatal stroke, resulting in lifelong disability for millions of people. However, our understanding of how the motor system develops following such early unilateral brain injury is increasing. Tools such as neuroimaging and brain stimulation are generating informed maps of the unique motor networks that emerge following perinatal stroke. As a focal injury of defined timing in an otherwise healthy brain, perinatal stroke represents an ideal human model of developmental plasticity. Here, we provide an introduction to perinatal stroke epidemiology and outcomes, before reviewing models of developmental plasticity after perinatal stroke. We then examine existing therapeutic approaches, including constraint, bimanual and other occupational therapies, and their potential synergy with non-invasive neurostimulation. We end by discussing the promise of exciting new therapies, including novel neurostimulation, brain-computer interfaces and robotics, all focused on improving outcomes after perinatal stroke.

Imaging Developmental and Interventional Plasticity Following Perinatal Stroke

Perinatal stroke occurs around the time of birth and leads to lifelong neurological disabilities including hemiparetic cerebral palsy. Magnetic resonance imaging (MRI) has revolutionized our understanding of developmental neuroplasticity following early injury, quantifying volumetric, structural, functional, and metabolic compensatory changes after perinatal stroke. Such techniques can also be used to investigate how the brain responds to treatment (interventional neuroplasticity). Here, we review the current state of knowledge of how established and emerging neuroimaging modalities are informing neuroplasticity models in children with perinatal stroke. Specifically, we review structural imaging characterizing lesion characteristics and volumetrics, diffusion tensor imaging investigating white matter tracts and networks, task-based functional MRI for localizing function, resting state functional imaging for characterizing functional connectomes, and spectroscopy examining neurometabolic changes. Key challenges and exciting avenues for future investigations are also considered.

Motor Skill Training May Restore Impaired Corticospinal Tract Fibers in Children With Cerebral Palsy

Background. In children with unilateral cerebral palsy (UCP), the fibers of the corticospinal tract (CST) emerging from the lesioned hemisphere are damaged following the initial brain injury. The extent to which the integrity of these fibers is restorable with training is unknown. Objective. To assess changes in CST integrity in children with UCP following Hand-and-Arm-Bimanual-Intensive-Therapy-Including-Lower-Extremity (HABIT-ILE) compared to a control group. Methods. Forty-four children with UCP participated in this study. Integrity of the CSTs was measured using diffusion tensor imaging before and after 2 weeks of HABIT-ILE (treatment group, n = 23) or 2 weeks apart without intensive treatment (control group, n = 18). Fractional anisotropy (FA) and mean diffusivity (MD) were the endpoints for assessing the integrity of CST. Results. As highlighted in our whole tract analysis, the FA of the CST originating from the nonlesioned and lesioned hemispheres increased significantly after therapy in the treatment group compared to the control group (group * test session interaction: P < .001 and P = .049, respectively). A decrease in MD was also observed in the CST emerging from the nonlesioned and lesioned hemispheres (group * time interaction: both P < .001). In addition, changes in manual ability correlated with changes in FA in both CSTs (r = 0.463, P = .024; r = 0.643, P < .001) and changes in MD in CST emerging from nonlesioned hemisphere (r = -0.662, P < .001). Conclusions. HABIT-ILE improves FA/MD in the CST and hand function of children with UCP, suggesting that CST fibers retain a capacity for functional restoration. This finding supports the application of intensive motor skill training in clinical practice for the benefit of numerous patients.

A functional Magnetic Resonance Imaging study of patients with Polar Type II/III complex shoulder instability

The pathophysiology of Stanmore Classification Polar type II/III shoulder instability is not well understood. Functional Magnetic Resonance Imaging was used to measure brain activity in response to forward flexion and abduction in 16 patients with Polar Type II/III shoulder instability and 16 age-matched controls. When a cluster level correction was applied patients showed significantly greater brain activity than controls in primary motor cortex (BA4), supramarginal gyrus (BA40), inferior frontal gyrus (BA44), precentral gyrus (BA6) and middle frontal gyrus (BA6): the latter region is considered premotor cortex. Using voxel level correction within these five regions a unique activation was found in the primary motor cortex (BA4) at MNI coordinates -38 -26 56. Activation was greater in controls compared to patients in the parahippocampal gyrus (BA27) and perirhinal cortex (BA36). These findings show, for the first time, neural differences in patients with complex shoulder instability, and suggest that patients are in some sense working harder or differently to maintain shoulder stability, with brain activity similar to early stage motor sequence learning. It will help to understand the condition, design better therapies and improve treatment of this group; avoiding the common clinical misconception that their recurrent shoulder dislocations are a form of attention-seeking.

Nonpharmacological rehabilitation interventions for motor and cognitive outcomes following pediatric stroke: a systematic review

The aim of this review was to evaluate the evidence for nonpharmacological rehabilitation interventions for motor and cognitive impairment following pediatric stroke. A literature search was conducted using multiple scientific databases. Studies were included if (1) the study population was > 50% pediatric (< 18 years) stroke, (2) a diagnosis of stroke was explicitly stated, (3) there were ≥ 3 pediatric stroke participants included in the study sample, and (4) motor or cognitive outcome measures were used to assess effect of treatment. Levels of evidence were assigned to each study to determine the strength of the evidence for each intervention. A total of 18 articles met inclusion criteria. Most studies (N = 14) examined rehabilitation of the upper limb, with constraint-induced movement therapy (CIMT) as the most common intervention. Overall, the evidence supports the use of CIMT, forced use therapy, repetitive transcranial magnetic stimulation, functional electrical stimulation, and robotics, but suggests no beneficial effect of transcranial direct current stimulation. Very few studies assessed interventions for the lower limb (N = 1) or cognitive impairment (N = 3).Conclusion: Effective rehabilitation approaches are important for optimizing outcomes in children who have had a stroke. Although the number of published clinical trials has increased in recent years, little evidence-based guidance exists for this clinical population. What is Known: • Pediatric stroke is a significant cause of disability in children that is often associated with long-term motor and cognitive sequelae. • There is a need to establish a knowledge base regarding available evidence-based rehabilitation therapies for this clinical population. What is New: • Most studies examining interventions for motor function focus on upper limb rehabilitation, whereas few studies have investigated interventions for improving lower limb or cognitive impairment. • An important gap exists regarding evidence-based rehabilitative treatment approaches for pediatric stroke.

Constraint-induced movement therapy in children with unilateral cerebral palsy

BACKGROUND

Unilateral cerebral palsy (CP) is a condition that affects muscle control and function on one side of the body. Children with unilateral CP experience difficulties using their hands together secondary to disturbances that occur in the developing fetal or infant brain. Often, the more affected limb is disregarded. Constraint-induced movement therapy (CIMT) aims to increase use of the more affected upper limb and improve bimanual performance. CIMT is based on two principles: restraining the use of the less affected limb (for example, using a splint, mitt or sling) and intensive therapeutic practice of the more affected limb.

OBJECTIVES

To evaluate the effect of constraint-induced movement therapy (CIMT) in the treatment of the more affected upper limb in children with unilateral CP.

SEARCH METHODS

In March 2018 we searched CENTRAL, MEDLINE, Embase, CINAHL, PEDro, OTseeker, five other databases and three trials registers. We also ran citation searches, checked reference lists, contacted experts, handsearched key journals and searched using Google Scholar.

SELECTION CRITERIA

Randomised controlled trials (RCTs), cluster-RCTs or clinically controlled trials implemented with children with unilateral CP, aged between 0 and 19 years, where CIMT was compared with a different form of CIMT, or a low dose, high-dose or dose-matched alternative form of upper-limb intervention such as bimanual intervention. Primarily, outcomes were bimanual performance, unimanual capacity and manual ability. Secondary outcomes included measures of self-care, body function, participation and quality of life.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened titles and abstracts to eliminate ineligible studies. Five review authors were paired to extract data and assess risk of bias in each included study. GRADE assessments were undertaken by two review authors.

MAIN RESULTS

We included 36 trials (1264 participants), published between 2004 and 2018. Sample sizes ranged from 11 to 105 (mean 35). Mean age was 5.96 years (standard deviation (SD) 1.82), range three months to 19.8 years; 53% male and 47% participants had left hemiplegia. Fifty-seven outcome measures were used across studies. Average length of CIMT programs was four weeks (range one to 10 weeks). Frequency of sessions ranged from twice weekly to seven days per week. Duration of intervention sessions ranged from 0.5 to eight hours per day. The mean total number of hours of CIMT provided was 137 hours (range 20 to 504 hours). The most common constraint devices were a mitt/glove or a sling (11 studies each).We judged the risk of bias as moderate to high across the studies.

KEY RESULTS

Primary outcomes at primary endpoint (immediately after intervention)CIMT versus low-dose comparison (e.g. occupational therapy)We found low-quality evidence that CIMT was more effective than a low-dose comparison for improving bimanual performance (mean difference (MD) 5.44 Assisting Hand Assessment (AHA) units, 95% confidence interval (CI) 2.37 to 8.51).CIMT was more effective than a low-dose comparison for improving unimanual capacity (Quality of upper extremity skills test (QUEST) - Dissociated movement MD 5.95, 95% CI 2.02 to 9.87; Grasps; MD 7.57, 95% CI 2.10 to 13.05; Weight bearing MD 5.92, 95% CI 2.21 to 9.6; Protective extension MD 12.54, 95% CI 8.60 to 16.47). Three studies reported adverse events, including frustration, constraint refusal and reversible skin irritations from casting.CIMT versus high-dose comparison (e.g. individualised occupational therapy, bimanual therapy)When compared with a high-dose comparison, CIMT was not more effective for improving bimanual performance (MD -0.39 AHA Units, 95% CI -3.14 to 2.36). There was no evidence that CIMT was more effective than a high-dose comparison for improving unimanual capacity in a single study using QUEST (Dissociated movement MD 0.49, 95% CI -10.71 to 11.69; Grasp MD -0.20, 95% CI -11.84 to 11.44). Two studies reported that some children experienced frustration participating in CIMT.CIMT versus dose-matched comparison (e.g. Hand Arm Bimanual Intensive Therapy, bimanual therapy, occupational therapy)There was no evidence of differences in bimanual performance between groups receiving CIMT or a dose-matched comparison (MD 0.80 AHA units, 95% CI -0.78 to 2.38).There was no evidence that CIMT was more effective than a dose-matched comparison for improving unimanual capacity (Box and Blocks Test MD 1.11, 95% CI -0.06 to 2.28; Melbourne Assessment MD 1.48, 95% CI -0.49 to 3.44; QUEST Dissociated movement MD 6.51, 95% CI -0.74 to 13.76; Grasp, MD 6.63, 95% CI -2.38 to 15.65; Weightbearing MD -2.31, 95% CI -8.02 to 3.40) except for the Protective extension domain (MD 6.86, 95% CI 0.14 to 13.58).There was no evidence of differences in manual ability between groups receiving CIMT or a dose-matched comparison (ABILHAND-Kids MD 0.74, 95% CI 0.31 to 1.18). From 15 studies, two children did not tolerate CIMT and three experienced difficulty.

AUTHORS' CONCLUSIONS

The quality of evidence for all conclusions was low to very low. For children with unilateral CP, there was some evidence that CIMT resulted in improved bimanual performance and unimanual capacity when compared to a low-dose comparison, but not when compared to a high-dose or dose-matched comparison. Based on the evidence available, CIMT appears to be safe for children with CP.

Intensive upper- and lower-extremity training for children with bilateral cerebral palsy: a quasi-randomized trial

AIM

An approach that simultaneously engages both the upper and lower extremities, hand-arm bimanual intensive therapy including lower extremity (HABIT-ILE), has recently demonstrated improvements in upper and lower extremities in children with unilateral cerebral palsy (CP). It is not known whether children with bilateral CP would benefit from this approach. The aim of this study was to examine the efficacy of HABIT-ILE in children with bilateral CP.

METHOD

A quasi-randomized trial design was used, whereby 20 participants (age 6-15y, Gross Motor Function Classification System levels II-IV, Manual Ability Classification System levels I-III) were assigned to a treatment (HABIT-ILE) or a comparison group in the order in which they were enrolled. Children in the HABIT-ILE group were assessed before and after 84 hours of intervention over 13 days, as well as at 3 months' follow-up. Children in the comparison group were assessed at the same time points. Children in both groups were assessed using the Gross Motor Function Measure (GMFM-66) and ABILHAND-Kids (primary measures), and six secondary measures.

RESULTS

A group×test session interaction indicated significant improvements in the HABIT-ILE group as assessed by the GMFM-66, lower-extremity performance (6-Minute Walk Test; Pediatric Balance Scale), functional upper-extremity abilities (ABILHAND-Kids/Pediatric Evaluation of Disability Inventory), and the dexterity of the less affected upper extremity.

CONCLUSION

HABIT-ILE is efficacious for improving both upper- and lower-extremity function in children with bilateral CP.

Constraint-Induced Movement Therapy for Children With Brain Tumors

PURPOSE

The purpose of this pilot study was to investigate the feasibility of a 3-week constraint-induced movement therapy program in children with brain tumors and upper extremity hemiplegia and to describe resultant change in extremity use.

METHODS

Affected arm use, health-related quality of life, and parent-reported feasibility of program participation were measured before and after the intervention and at a 3-month follow-up visit.

RESULTS

All 9 participants completed the entire study. The quality and amount of affected arm use improved significantly; gains were maintained at the 3-month follow-up evaluation. Some parents (44%) reported that program participation was difficult; however, all reported satisfaction with the program. Participants did not experience negative changes in health-related quality of life during the intervention, indicating that they tolerated the program well.

CONCLUSIONS

Findings suggest that a child with hemiplegia as a result of a brain tumor can adhere to and benefit from a constraint-induced movement therapy program.

Advancing non-invasive neuromodulation clinical trials in children: Lessons from perinatal stroke

Applications of non-invasive brain stimulation including therapeutic neuromodulation are expanding at an alarming rate. Increasingly established scientific principles, including directional modulation of well-informed cortical targets, are advancing clinical trial development. However, high levels of disease burden coupled with zealous enthusiasm may be getting ahead of rational research and evidence. Experience is limited in the developing brain where additional issues must be considered. Properly designed and meticulously executed clinical trials are essential and required to advance and optimize the potential of non-invasive neuromodulation without risking the well-being of children and families. Perinatal stroke causes most hemiplegic cerebral palsy and, as a focal injury of defined timing in an otherwise healthy brain, is an ideal human model of developmental plasticity. Advanced models of how the motor systems of young brains develop following early stroke are affording novel windows of opportunity for neuromodulation clinical trials, possibly directing neuroplasticity toward better outcomes. Reviewing the principles of clinical trial design relevant to neuromodulation and using perinatal stroke as a model, this article reviews the current and future issues of advancing such trials in children.

Speech production gains following constraint-induced movement therapy in children with hemiparesis

PURPOSE

The purpose of this study was to investigate changes in speech skills of children who have hemiparesis and speech impairment after participation in a constraint-induced movement therapy (CIMT) program. While case studies have reported collateral speech gains following CIMT, the effect of CIMT on speech production has not previously been directly investigated to the knowledge of these investigators.

METHODS

Eighteen children with hemiparesis and co-occurring speech impairment participated in a 21-day clinical CIMT program. The Goldman-Fristoe Test of Articulation-2 (GFTA-2) was used to assess children's articulation of speech sounds before and after the intervention. Changes in percent of consonants correct (PCC) on the GFTA-2 were used as a measure of change in speech production.

RESULTS

Children made significant gains in PCC following CIMT. Gains were similar in children with left and right-sided hemiparesis, and across age groups.

CONCLUSION

This study reports significant collateral gains in speech production following CIMT and suggests benefits of CIMT may also spread to speech motor domains.

Surface-Based fMRI-Driven Diffusion Tractography in the Presence of Significant Brain Pathology: A Study Linking Structure and Function in Cerebral Palsy

Diffusion MRI (dMRI) tractography analyses are difficult to perform in the presence of brain pathology. Automated methods that rely on cortical parcellation for structural connectivity studies often fail, while manually defining regions is extremely time consuming and can introduce human error. Both methods also make assumptions about structure-function relationships that may not hold after cortical reorganisation. Seeding tractography with functional-MRI (fMRI) activation is an emerging method that reduces these confounds, but inherent smoothing of fMRI signal may result in the inclusion of irrelevant pathways. This paper describes a novel fMRI-seeded dMRI-analysis pipeline based on surface-meshes that reduces these issues and utilises machine-learning to generate task specific white matter pathways, minimising the requirement for manually-drawn ROIs. We directly compared this new strategy to a standard voxelwise fMRI-dMRI approach, by investigating correlations between clinical scores and dMRI metrics of thalamocortical and corticomotor tracts in 31 children with unilateral cerebral palsy. The surface-based approach successfully processed more participants (87%) than the voxel-based approach (65%), and provided significantly more-coherent tractography. Significant correlations between dMRI metrics and five clinical scores of function were found for the more superior regions of these tracts. These significant correlations were stronger and more frequently found with the surface-based method (15/20 investigated were significant; R² = 0.43–0.73) than the voxelwise analysis (2 sig. correlations; 0.38 & 0.49). More restricted fMRI signal, better-constrained tractography, and the novel track-classification method all appeared to contribute toward these differences.

Neuroplastic Sensorimotor Resting State Network Reorganization in Children With Hemiplegic Cerebral Palsy Treated With Constraint-Induced Movement Therapy

Using resting state functional magnetic resonance imaging (MRI), we aim to understand the neurologic basis of improved function in children with hemiplegic cerebral palsy treated with constraint-induced movement therapy. Eleven children including 4 untreated comparison subjects diagnosed with hemiplegic cerebral palsy were recruited from 3 clinical centers. MRI and clinical data were gathered at baseline and 1 month for both groups, and 6 months later for the case group only. After constraint therapy, the sensorimotor resting state network became more bilateral, with balanced contributions from each hemisphere, which was sustained 6 months later. Sensorimotor resting state network reorganization after therapy was correlated with a change in the Quality of Upper Extremity Skills Test score at 1 month (r = 0.79, P = .06), and Canadian Occupational Performance Measure scores at 6 months (r = 0.82, P = .05). This clinically correlated resting state network reorganization provides further evidence of the neuroplastic mechanisms underlying constraint-induced movement therapy.

Early childhood constraint therapy for sensory/motor impairment in cerebral palsy: a randomised clinical trial protocol

INTRODUCTION

Cerebral palsy (CP) is the most common physical disability in childhood. It is a disorder resulting from sensory and motor impairments due to perinatal brain injury, with lifetime consequences that range from poor adaptive and social function to communication and emotional disturbances. Infants with CP have a fundamental disadvantage in recovering motor function: they do not receive accurate sensory feedback from their movements, leading to developmental disregard. Constraint-induced movement therapy (CIMT) is one of the few effective neurorehabilitative strategies shown to improve upper extremity motor function in adults and older children with CP, potentially overcoming developmental disregard.

METHODS AND ANALYSIS

This study is a randomised controlled trial of children 12-24 months corrected age studying the effectiveness of CIMT combined with motor and sensory-motor interventions. The study population will comprise 72 children with CP and 144 typically developing children for a total of N=216 children. All children with CP, regardless of group allocation will continue with their standard of care occupational and physical therapy throughout the study. The research material collected will be in the form of data from high-density array event-related potential scan, standardised assessment scores and motion analysis scores.

ETHICS AND DISSEMINATION

The study protocol was approved by the Institutional Review Board. The findings of the trial will be disseminated through peer-reviewed journals and scientific conferences.

TRIAL REGISTRATION NUMBER

NCT02567630.

Synergistic effect of combined transcranial direct current stimulation/constraint-induced movement therapy in children and young adults with hemiparesis: study protocol

Background

Perinatal stroke occurs in more than 1 in 2,500 live births and resultant congenital hemiparesis necessitates investigation into interventions which may improve long-term function and decreased burden of care beyond current therapies (http://www.cdc.gov/ncbddd/cp/data.html). Constraint-Induced Movement Therapy (CIMT) is recognized as an effective hemiparesis rehabilitation intervention . Transcranial direct current stimulation as an adjunct treatment to CIMT may potentiate neuroplastic responses and improve motor function. The methodology of a clinical trial in children designed as a placebo-controlled, serial –session, non-invasive brain stimulation trial incorporating CIMT is described here. The primary hypotheses are 1) that no serious adverse events will occur in children receiving non-invasive brain stimulation and 2) that children in the stimulation intervention group will show significant improvements in hand motor function compared to children in the placebo stimulation control group.

Methods/design

A randomized, controlled, double-blinded clinical trial. Twenty children and/or young adults (ages 8–21) with congenital hemiparesis, will be enrolled. The intervention group will receive ten 2-hour sessions of transcranial direct current stimulation combined with constraint-induced movement therapy and the control group will receive sham stimulation with CIMT. The primary outcome measure is safety assessment of transcranial direct current stimulation by physician evaluation, vital sign monitoring and symptom reports. Additionally, hand function will be evaluated using the Assisting Hand Assessment, grip strength and assessment of goals using the Canadian Occupational Performance Measure. Neuroimaging will confirm diagnoses, corticospinal tract integrity and cortical activation. Motor cortical excitability will also be examined using transcranial magnetic stimulation techniques.

Discussion

Combining non-invasive brain stimulation and CIMT interventions has the potential to improve motor function in children with congenital hemiparesis beyond each intervention independently. Such a combined intervention has the potential to benefit an individual throughout their lifetime.

Trial registration

Clinicaltrials.gov, NCT02250092Registered 18 September 2014

The promotion of recovery through rehabilitation after acquired brain injury in children

A degree of motor recovery is typically seen after acquired brain injury in children. The extent to which rehabilitation efforts can claim credit for this is disputed. Strong correlations between late impairment outcomes and early severity and impairment indices are seen both in adults and children. These correlations have been interpreted by some as evidence that recovery is largely intrinsic and that any additional rehabilitation effects are small. Such views are belied by published animal studies demonstrating the possibility of large rehabilitation effects. Animal models suggest that to achieve similar rehabilitation treatment effect sizes in clinical practice, rehabilitation 'doses' should be greater, rehabilitation efforts should start sooner, and premature accommodation of impairment should be avoided.

Cortical activation and inter-hemispheric sensorimotor coherence in individuals with arm dystonia due to childhood stroke

OBJECTIVE

Dystonia is a disabling motor disorder often without effective therapies. To better understand the genesis of dystonia after childhood stroke, we analyzed electroencephalographic (EEG) recordings in this population.

METHODS

Resting spectral power of EEG signals over bilateral sensorimotor cortices (Powrest), resting inter-hemispheric sensorimotor coherence (Cohrest), and task-related changes in power (TRPow) and coherence (TRCoh) during wrist extension were analyzed in individuals with dystonia (age 20±3years) and healthy volunteers (age 17±5years).

RESULTS

Ipsilesional TRPow decrease was significantly lower in patients than controls during the more affected wrist task. Force deficits of the affected wrist correlated with reduced alpha TRPow decrease on the ipsilesional and not the contralesional hemisphere. Cohrest was significantly lower in patients than controls, and correlated with more severe dystonia and poorer hand function. Powrest and TRCoh were similar between groups.

CONCLUSIONS

The association between weakness and cortical activation during wrist extension highlights the importance of ipsilesional sensorimotor activation on function. Reduction of Cohrest in patients reflects a loss of inter-hemispheric connectivity that may result from structural changes and neuroplasticity, potentially contributing to the development of dystonia.

SIGNIFICANCE

Cortical and motor dysfunction are correlated in patients with childhood stroke and may in part explain the genesis of dystonia.

Microstructure of transcallosal motor fibers reflects type of cortical (re-)organization in congenital hemiparesis

BACKGROUND

Early unilateral brain lesions can lead to different types of corticospinal (re-)organization of motor networks. In one group of patients, the contralesional hemisphere exerts motor control not only over the contralateral non-paretic hand but also over the (ipsilateral) paretic hand, as the primary motor cortex is (re-)organized in the contralesional hemisphere. Another group of patients with early unilateral lesions shows "normal" contralateral motor projections starting in the lesioned hemisphere.

AIM

We investigated how these different patterns of cortical (re-)organization affect interhemispheric transcallosal connectivity in patients with congenital hemiparesis.

METHOD

Eight patients with ipsilateral motor projections (group IPSI) versus 7 patients with contralateral motor projections (group CONTRA) underwent magnetic resonance diffusion tensor imaging (DTI). The corpus callosum (CC) was subdivided in 5 areas (I-V) in the mid-sagittal slice and volumetric information. The following diffusion parameters were calculated: fractional anisotropy (FA), trace, radial diffusivity (RD), and axial diffusivity (AD).

RESULTS

DTI revealed significantly lower FA, increased trace and RD for group IPSI compared to group CONTRA in area III of the corpus callosum, where transcallosal motor fibers cross the CC. In the directly neighboring area IV, where transcallosal somatosensory fibers cross the CC, no differences were found for these DTI parameters between IPSI and CONTRA. Volume of callosal subsections showed significant differences for area II (connecting premotor cortices) and III, where group IPSI had lower volume.

INTERPRETATION

The results of this study demonstrate that the callosal microstructure in patients with congenital hemiparesis reflects the type of cortical (re-)organization. Early lesions disrupting corticospinal motor projections to the paretic hand consecutively affect the development or maintenance of transcallosal motor fibers.

Feasibility of event-related potential methodology to evaluate changes in cortical processing after rehabilitation in children with cerebral palsy: a pilot study

This study examined the feasibility of using event-related potentials (ERPs) to measure changes in cortical processing following an established rehabilitative intervention (constraint-induced movement therapy, CIMT) for children with cerebral palsy (CP). Sixteen participants with a diagnosis of hemiparetic CP, with a median age of 6 years, were assessed pre and immediately post CIMT and at 6-month follow-up, using a picture-word match/mismatch discrimination task and standard neurobehavioral measures. Intervention effects were evident in improved performance on behavioral tests of sensory and motor function and the increased mean ERP amplitude of the N400 match/mismatch response on the side ipsilateral to the lesion. These effects were maintained 6 months after the intervention. No such changes were observed on the side contralateral to the lesion. This research suggests that ERPs can measure rehabilitation-induced changes in neural function in children with CP.

Changes in diffusion tensor tractographic findings associated with constraint-induced movement therapy in young children with cerebral palsy

OBJECTIVE

The objective of the study was to determine whether constraint-induced movement therapy (CIMT) could lead to changes in diffusion tensor tractography (DTT) associated with clinical improvement in young children with unilateral cerebral palsy (CP).

METHODS

A standardized pediatric CIMT protocol (4weeks, 120h of constraint) was used on 10 children with unilateral CP who were younger than 5years. DTT was performed in five participants before and after the intervention. Clinical outcome was measured by using the Pediatric Motor Activity Log (PMAL), Quality of Upper Extremity Skills Test (QUEST), and self-care domain of the Pediatric Evaluation of Disability Inventory.

RESULTS

In two patients, the affected corticospinal tract (CST) visible on pretreatment DTT became more prominent on posttreatment DTT. In one patient, the affected CST was not visible on pretreatment DTT, but was visible on posttreatment DTT. All the clinical outcomes significantly improved in the CIMT group compared with the control group. Changes in the PMAL how often scale (PMAL-HO) score significantly differed between the CIMT and control groups.

CONCLUSIONS

Changes in the properties of the affected CST on DTT were accompanied with improved arm function after CIMT in the children with CP.

SIGNIFICANCE

CIMT might lead to CST reorganization in young children with CP.

Brain reorganization following intervention in children with congenital hemiplegia: a systematic review

Noninvasive rehabilitation strategies for children with unilateral cerebral palsy are routinely used to improve hand motor function, activity, and participation. Nevertheless, the studies exploring their effects on brain structure and function are very scarce. Recently, structural neuroplasticity was demonstrated in adult poststroke patients, in response to neurorehabilitation. Our purpose is to review current evidence on the effects of noninvasive intervention strategies on brain structure or function, in children with unilateral cerebral palsy. The main literature databases were searched up to October 2013. We included studies where the effects of upper limb training were evaluated at neurofunctional and/or neurostructural levels. Only seven studies met our selection criteria; selected studies were case series, six using the intervention of the constraint-induced movement therapy (CIMT) and one used virtual reality therapy (VR). CIMT and VR seem to produce measurable neuroplastic changes in sensorimotor cortex associated with enhancement of motor skills in the affected limb. However, the level of evidence is limited, due to methodological weaknesses and small sample sizes of available studies. Well-designed and larger experimental studies, in particular RCTs, are needed to strengthen the generalizability of the findings and to better understand the mechanism of intervention-related brain plasticity in children with brain injury.

Two types of exercise-induced neuroplasticity in congenital hemiparesis: a transcranial magnetic stimulation, functional MRI, and magnetoencephalography study

AIM

Early unilateral brain lesions can lead to a persistence of ipsilateral corticospinal projections from the contralesional hemisphere, which can enable the contralesional hemisphere to exert motor control over the paretic hand. In contrast to the primary motor representation (M1), the primary somatosensory representation (S1) of the paretic hand always remains in the lesioned hemisphere. Here, we report on differences in exercise-induced neuroplasticity between individuals with such ipsilateral motor projections (ipsi) and individuals with early unilateral lesions but 'healthy' contralateral motor projections (contra).

METHOD

Sixteen children and young adults with congenital hemiparesis participated in the study (contralateral [Contra] group: n=7, four females, three males; age range 10-30y, median age 16y; ipsilateral [Ipsi] group: n=9, four females, five males; age range 11-31y, median age 12y; Manual Ability Classification System levels I to II in all individuals in both groups). The participants underwent a 12-day intervention of constraint-induced movement therapy (CIMT), consisting of individual training (2h/d) and group training (8h/d). Before and after CIMT, hand function was tested using the Wolf Motor Function Test (WMFT) and diverging neuroplastic effects were observed by transcranial magnetic stimulation (TMS), functional magnetic resonance imaging (fMRI), and magnetoencephalography (MEG). Statistical analysis of TMS data was performed using the non-parametric Wilcoxon signed-rank test for pair-wise comparison; for fMRI standard statistical parametric and non-parametric mapping (SPM5, SnPM3) procedures (first level/second level) were carried out. Statistical analyses of MEG data involved analyses of variance (ANOVA) and t-tests.

RESULTS

While MEG demonstrated a significant increase in S1 activation in both groups (p=0.012), TMS showed a decrease in M1 excitability in the Ipsi group (p=0.036), but an increase in M1 excitability in the Contra group (p=0.043). Similarly, fMRI showed a decrease in M1 activation in the Ipsi group, but an increase in activation in the M1-S1 region in the Contra group (for both groups p<0.001 [SnPM3] within the search volume).

INTERPRETATION

Different patterns of sensorimotor (re)organization in individuals with early unilateral lesions show, on a cortical level, different patterns of exercise-induced neuroplasticity. The findings help to improve the understanding of the general principles of sensorimotor learning and will help to develop more specific therapies for different pathologies in congenital hemiparesis.

Efficacy of modified constraint induced movement therapy in improving upper limb function in children with hemiplegic cerebral palsy: a randomized controlled trial

PURPOSE

The objective of this randomized single blind (outcome assessor) controlled trial was to evaluate the efficacy of 4 weeks of modified constraint induced movement therapy (mCIMT) in improving upper limb function in 3-8 years old children with hemiplegic cerebral palsy.

METHODS

Thirty-one children were randomly assigned to receive the mCIMT (N=16) with conventional therapy or conventional therapy alone (N=15). Children were evaluated three times (at enrollment, follow up at 4 weeks and 12 weeks). The primary outcome measure was difference in "change in mean total QUEST scores" at 4 weeks of intervention between the intervention and the control arm.

RESULTS

After 4 weeks of intervention, mCIMT group showed significant change in the affected upper limb in QUEST scores (10.7 ± 5.2 vs 1.4 ± 1.7, p<0.001) and time (s) to complete nine-hole-pegboard test compared with control group [60(0-130) vs 5(-12 to 30), p<0.001]. The improvement observed in upper limb function after 4 weeks of intervention persisted 8 weeks after discontinuation of intervention in mCIMT group.

CONCLUSION

The modified constraint induced movement therapy appears to be effective in improving upper limb function in 3-8 years old hemiplegic cerebral palsy children.

MRI predicts efficacy of constraint-induced movement therapy in children with brain injury

Using resting state (RS) functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), we identified the predictors of clinical improvement following constraint-induced movement therapy (CIMT) in pediatric patients with chronic hemiplegia.From 14 children with congenital or acquired brain injury and 10 sex- and age-matched healthy controls, brain dual-echo, DTI and RS fMRI sequences were acquired before CIMT. The Quality of Upper Extremities Skills Test and the Gross Motor Function Measure (GMFM) were administered at baseline, at the end of CIMT (10 weeks), and after 6 months. Mean diffusivity and fractional anisotropy (FA) were measured in the lesion responsible for the clinical symptomatology, the affected and unaffected corticospinal tract (CST), motor transcallosal fibers, and uncinate fasciculus (as an internal control). Independent component analysis was used to identify the sensorimotor RS network. The ability of baseline MRI variables to predict clinical changes over time was assessed using multivariate linear models. At baseline, patients had increased mean diffusivity in the symptomatic lesion and decreased FA in the symptomatic lesion, affected corticospinal tract, and motor transcallosal fibers. A reduced RS functional connectivity was found in the bilateral cerebellum, left precentral gyrus, and right secondary sensorimotor cortex. At follow up, Quality of Upper Extremities Skills Test and GMFM scales improved significantly. Baseline average lesion FA predicted clinical improvement at week 10, and baseline functional connectivity of the right secondary sensorimotor cortex and cerebellum predicted GMFM improvement at month 6. DTI and RS fMRI offer promising and objective markers to predict clinical outcomes following CIMT in pediatric patients with congenital or acquired hemiplegia.

Can noninvasive brain stimulation measure and modulate developmental plasticity to improve function in stroke-induced cerebral palsy?

The permanent nature of motor deficits is a consistent cornerstone of cerebral palsy definitions. Such pessimism is disheartening to children, families, and researchers alike and may no longer be appropriate for it ignores the fantastic plastic potential of the developing brain. Perinatal stroke is presented as the ideal human model of developmental neuroplasticity following distinct, well-defined, focal perinatal brain injury. Elegant animal models are merging with human applied technology methods, including noninvasive brain stimulation for increasingly sophisticated models of plastic motor development following perinatal stroke. In this article, how potential central therapeutic targets are identified and potentially modulated to enhance motor function within these models is discussed. Also, future directions and emerging clinical trials are reviewed.

Modeling developmental plasticity after perinatal stroke: defining central therapeutic targets in cerebral palsy

Perinatal stroke is presented as the ideal human model of developmental neuroplasticity. The precise timing, mechanisms, and locations of specific perinatal stroke diseases provide common examples of well defined, focal, perinatal brain injuries. Motor disability (hemiparetic cerebral palsy) constitutes the primary adverse outcome and the focus of models explaining how motor systems develop in health and after early injury. Combining basic science animal work with human applied technology (functional magnetic resonance imaging, diffusion tensor imaging, and transcranial magnetic stimulation), a model of plastic motor development after perinatal stroke is presented. Potential central therapeutic targets are revealed. The means to measure and modulate these targets, including evidence-based rehabilitation therapies and noninvasive brain stimulation, are suggested. Implications for clinical trials and future directions are discussed.

Constraint-induced movement therapy promotes brain functional reorganization in stroke patients with hemiplegia

Stroke patients with hemiplegia exhibit flexor spasms in the upper limb and extensor spasms in the lower limb, and their movement patterns vary greatly. Constraint-induced movement therapy is an upper limb rehabilitation technique used in stroke patients with hemiplegia; however, studies of lower extremity rehabilitation are scarce. In this study, stroke patients with lower limb hemiplegia underwent conventional Bobath therapy for 4 weeks as baseline treatment, followed by constraint-induced movement therapy for an additional 4 weeks. The 10-m maximum walking speed and Berg balance scale scores significantly improved following treatment, and lower extremity motor function also improved. The results of functional MRI showed that constraint-induced movement therapy alleviates the reduction in cerebral functional activation in patients, which indicates activation of functional brain regions and a significant increase in cerebral blood perfusion. These results demonstrate that constraint-induced movement therapy promotes brain functional reorganization in stroke patients with lower limb hemiplegia.

Outcomes of a clinic-based pediatric constraint-induced movement therapy program

A single-group pre- and post-test design was used to evaluate functional outcomes of a constraint-induced movement therapy (CIMT) protocol implemented in an outpatient therapy center. The participants were 29 children with hemiplegia, ages 1.6-19.1 years old. The less-involved upper limb was placed in a cast that was worn 24 hr a day, 7 days a week. Individual therapy sessions took place 5 days/week. Children received 3 or 6 hr therapy sessions for 16-19 days followed by 2-5 days in which bimanual tasks were performed. Outcomes were assessed at baseline and following CIMT. Statistically significant gains were made on the Melbourne Assessment of Unilateral Upper Limb Function, Quality of Upper Extremity Skills Test (except the Protective Extension subtest), Assisting Hand Assessment, and the Canadian Occupational Performance Measure. The effect sizes varied from 0.46 to 0.70 indicating a moderate effect size. The results support the effectiveness of CIMT provided through a center-based program.

Spatiotemporal relations of primary sensorimotor and secondary motor activation patterns mapped by NIR imaging

Functional near infrared (fNIR) imaging was used to identify spatiotemporal relations between spatially distinct cortical regions activated during various hand and arm motion protocols. Imaging was performed over a field of view (FOV, 12 x 8.4 cm) including the secondary motor, primary sensorimotor, and the posterior parietal cortices over a single brain hemisphere. This is a more extended FOV than typically used in current fNIR studies. Three subjects performed four motor tasks that induced activation over this extended FOV. The tasks included card flipping (pronation and supination) that, to our knowledge, has not been performed in previous functional magnetic resonance imaging (fMRI) or fNIR studies. An earlier rise and a longer duration of the hemodynamic activation response were found in tasks requiring increased physical or mental effort. Additionally, analysis of activation images by cluster component analysis (CCA) demonstrated that cortical regions can be grouped into clusters, which can be adjacent or distant from each other, that have similar temporal activation patterns depending on whether the performed motor task is guided by visual or tactile feedback. These analyses highlight the future potential of fNIR imaging to tackle clinically relevant questions regarding the spatiotemporal relations between different sensorimotor cortex regions, e.g. ones involved in the rehabilitation response to motor impairments.

Treatment of congenital hemiparesis with pediatric constraint-induced movement therapy

To determine efficacy of pediatric Constraint-Induced Movement therapy, 20 children with congenital hemiparesis (ages 2 to 6 years) were randomly assigned to receive the treatment or usual care. Controls crossed over to the therapy after 6 months. Children receiving the therapy first exhibited emergence of more new classes of motor patterns and skills (eg, crawling, thumb-forefinger prehension; 6.4 vs 0.02, P < .0001, effect size d = 1.3), and demonstrated significant gains in spontaneous use of the more affected arm at home (2.2 vs 0.1, P < .0001, d = 3.8) and in a laboratory motor function test. Depending on the measure, benefits were maintained (range, no loss to 68% retention over 6 months). When controls crossed over to the therapy, they exhibited improvements as great as or greater than those receiving therapy first. Thus, Constraint-Induced Movement therapy appears to be efficacious for young children with hemiparesis consequent to congenital stroke.

Manual, semi-automated, and automated delineation of chronic brain lesions: a comparison of methods

The exact delineation of chronic brain lesions is a crucial step when investigating the relationship between brain structure and (dys-)function. For this, manual tracing, although very time-consuming, is still the gold standard. In order to assess the possible contributions from other methods, we compared manual tracing of lesion boundaries with a newly developed semi-automated and a fully automated approach for lesion definition in a sample of chronic stroke patients (n=11, 5m, median age 12, range 10-30years). Manual tracing requires substantially more human input (4.8-9.6h/subject) than semi-automated (24.9min/subject) and automated processing (1min/subject). When compared with manual tracing as the gold standard, both the semi-automated (tested with 4 different smoothing filters) and the automated approach towards lesion definition performed on an acceptable level, with an average Dice's similarity index of .53-.60 (semi-automated) and .49 (automated processing). In all semi-automated and automated approaches, larger lesions were identified with a significantly higher performance than smaller lesions, as were central versus peripheral voxels, indicating that the surface-to-volume ratio explains this trend. The automated approach failed to identify two lesions. In several cases, indirect lesion effects (such as enlarged ventricles) were detected using the semi-automated or the automated approach. We conclude that manual tracing remains the gold standard for exact lesion delineation, but that semi-automated and automated approaches may be alternatives for larger lesions and/or larger studies. The detection of indirect lesion effects may be another application of such approaches in the future.

Relationship between functional connectivity and sensory impairment: red flag or red herring?

Resting-state functional magnetic resonance imaging (fMRI) can be used to study the functional connectivity in the somatosensory system. However, the relationship between sensory network connectivity, sensory deficits, and structural abnormality remains poorly understood. Previously, we investigated the motor network in children with congenital hemiparesis due to middle cerebral artery strokes (MCA, n = 6) or periventricular lesions (PL, n = 8). In the present study, we validate the use of interleaved resting-state data from blocked fMRI designs to investigate the somatosensory network in these patients. The approach was validated by assessing the predicted "crossed-over" connectivity between the cerebral cortex and the cerebellum. Furthermore, the impact on the volume of gray-matter (GM) in primary (S1) and secondary (S2) somatosensory cortex on functional connectivity measures was investigated. We were able to replicate the well-known "crossed-over" pattern of functional connectivity between cerebral and cerebellar cortex. The MCA group displayed more sensory deficit and significantly reduced functional connectivity in the lesioned S2 (but not in lesioned S1) when compared with the PL group. However, when accounting for GM volume loss, this difference disappeared. This study demonstrates the applicability of analyzing resting-state connectivity in patients with brain lesions. Reductions of functional connectivity within the somatosensory network were associated with sensory deficits, but were fully explained by the underlying GM damage.

Bilateral and unilateral arm training improve motor function through differing neuroplastic mechanisms: a single-blinded randomized controlled trial

BACKGROUND AND PURPOSE

This randomized controlled trial tests the efficacy of bilateral arm training with rhythmic auditory cueing (BATRAC) versus dose-matched therapeutic exercises (DMTEs) on upper-extremity (UE) function in stroke survivors and uses functional magnetic resonance imaging (fMRI) to examine effects on cortical reorganization.

METHODS

A total of 111 adults with chronic UE paresis were randomized to 6 weeks (3×/week) of BATRAC or DMTE. Primary end points of UE assessments of Fugl-Meyer UE Test (FM) and modified Wolf Motor Function Test Time (WT) were performed 6 weeks prior to and at baseline, after training, and 4 months later. Pretraining and posttraining, fMRI for UE movement was evaluated in 17 BATRAC and 21 DMTE participants.

RESULTS

The improvements in UE function (BATRAC: FM Δ = 1.1 + 0.5, P = .03; WT Δ = -2.6 + 0.8, P < .00; DMTE: FM Δ = 1.9 + 0.4, P < .00; WT Δ = -1.6 + 0.7; P = .04) were comparable between groups and retained after 4 months. Satisfaction was higher after BATRAC than DMTE (P = .003). BATRAC led to significantly higher increase in activation in ipsilesional precentral, anterior cingulate and postcentral gyri, and supplementary motor area and contralesional superior frontal gyrus (P < .05). Activation change in the latter was correlated with improvement in the WMFT (P = .01).

CONCLUSIONS

BATRAC is not superior to DMTE, but both rehabilitation programs durably improve motor function for individuals with chronic UE hemiparesis and with varied deficit severity. Adaptations in brain activation are greater after BATRAC than DMTE, suggesting that given similar benefits to motor function, these therapies operate through different mechanisms.

Upper limb function and brain reorganization after constraint-induced movement therapy in children with hemiplegia

OBJECTIVE

The aims of this study were to (1) investigate the effectiveness of CIMT for children with hemiplegia, (2) determine the feasibility of using fMRI for describing brain activity patterns before and after CIMT and (3) describe changes in brain reorganization after CIMT in children with hemiplegia using fMRI.

DESIGN

Before and after study with one group.

METHODS

Ten children aged 7-14 years (M = 11.0, SD = 2.5) with hemiplegia received CIMT over a 2-week period using a before and after design. Clinical measures included the Melbourne Assessment of Unilateral Upper Limb Function, upper limb kinematics and parent questionnaire. Children were measured with fMRI before and after CIMT.

RESULTS

Findings showed that CIMT may be effective at improving upper limb function in some, but not all children; those children with a moderate degree of impairment seemed to benefit the most. fMRI findings correlated moderately with clinical measures.

CONCLUSION

Although unique challenges with fMRI data collection exist for this population, it provides potentially valuable information to better understand mechanisms of change after interventions such as CIMT.

Bound for success: a systematic review of constraint-induced movement therapy in children with cerebral palsy supports improved arm and hand use

BACKGROUND

Constraint-induced movement therapy (CIMT) is a potentially effective intervention for children with hemiplegic cerebral palsy (CP).

PURPOSE

The objectives of this systematic review are: (1) to investigate whether CIMT is supported with valid research of its effectiveness and (2) to identify key characteristics of the child and intervention protocol associated with the effects of CIMT.

DATA SOURCES AND STUDY SELECTION

A search of MEDLINE (1966 through March 2009), Entrez PubMed (1966 through March 2009), EMBASE (1980 through March 2009), CINAHL (1982 through March 2009), PsychINFO (1887 through March 2009), and Web of Science (1900 through March 2009) produced 23 relevant studies.

DATA EXTRACTION AND SYNTHESIS

The 2 objectives of the review were addressed by: (1) scoring the validity and level of evidence for each study and calculating evidence-based statistics, if possible, and (2) recording and summarizing the inclusion and exclusion criteria, type and duration of constraint, intervention and study durations, and outcomes based on the International Classification of Functioning, Disability and Health (ICF).

LIMITATIONS

Only studies published in journals and in English were included in the systematic review.

CONCLUSIONS

Studies varied widely in type and rigor of design; subject, constraint, and intervention characteristics; and ICF level for outcome measures. One outcome measure at the body functions and structure level and 4 outcome measures at the activity level had large and significant treatment effects (d > or = .80), and these findings were from the most rigorous studies. Evidence from more-rigorous studies demonstrated an increased frequency of use of the upper extremity following CIMT for children with hemiplegic CP. The critical threshold for intensity that constitutes an adequate dose cannot be determined from the available research. Further research should include a priori power calculations, more-rigorous designs and comparisons of different components of CIMT in relation to specific children, and measures of potential impacts on the developing brain.

Pediatric constraint-induced movement therapy is associated with increased contralateral cortical activity on functional magnetic resonance imaging

The mechanism behind constraint-induced movement therapy (constraint therapy) success is unknown. Study objectives were to evaluate cortical change after modified constraint therapy and explore a novel approach to quantify developmental disregard. Five participants underwent modified constraint therapy. Functional magnetic resonance imaging (MRI) and clinical measures were done pretreatment and posttreatment. Developmental disregard indices were calculated. Four participants showed clinical improvement posttreatment. Functional MRI laterality indices were variable pretreatment and exclusively contralateral among participants posttreatment. The disregard index range was -12.9 to 62.6 among participants. Disregard indices were correlated with change scores after treatment on the Pediatric Motor Activity Log amount of use domain (r = .93, P = .02), Assisting Hand Assessment (r = .93, P = .02), and grip strength (r = .92, P = .03). Study results suggest that a shift to or persistence of contralateral cortical activity for affected hand movement is important for constraint therapy mechanism of action; and developmental disregard may be a predictor of positive response to treatment.

Motor cortex plasticity in ischemic perinatal stroke: a transcranial magnetic stimulation and functional MRI study

To assess motor cortex plasticity after constraint-induced movement therapy in patients with ischemic perinatal stroke, functional MRI and transcranial magnetic stimulation were applied. Seven hemiparetic patients with ischemic perinatal stroke of the middle cerebral artery and preserved crossed corticospinal projections to the paretic hand were studied before and after 12 days of constraint-induced movement therapy. After therapy, all patients demonstrated improved manual motor function. Transcranial magnetic stimulation of the motor cortex of the affected hemisphere revealed a significant increase of motor-evoked potential amplitude recorded from the paretic hand, whereas no significant change was detected in the nonparetic hand after transcranial magnetic stimulation of the contralesional hemisphere. Functional MRI revealed increased activation of the contralateral central region (including primary sensorimotor cortex) and supplementary motor area during active movement of the paretic hand. No change in functional MRI activation was detected during passive movement of the paretic hand or during active and passive movement of the nonparetic hand. In ischemic perinatal stroke with crossed corticospinal projections, constraint-induced movement therapy induces neuroplastic changes on the synaptic level, detected as increased excitability (transcranial magnetic stimulation) and increased task-related brain activation (functional MRI) in the primary motor cortex of the lesioned hemisphere.

Constraint-induced movement therapy for individuals after cerebral hemispherectomy: a case series

BACKGROUND AND PURPOSE

This case report describes the feasibility and efficacy of the use of constraint-induced movement therapy (CIMT) in 4 individuals (aged 12-22 years) who underwent cerebral hemispherectomy (age at time of surgery=4-10 years). The aims of this case series were: (1) to evaluate the feasibility of this therapeutic approach involving a shortened version of CIMT, (2) to examine improvements that occurred within the upper extremity of the hemiparetic side, (3) to investigate the feasibility of conducting brain imaging in individuals with depressed mental ages, and (4) to examine changes in the sensorimotor cortex following intervention.

CASE DESCRIPTION

The patients received a shortened version of CIMT for 3 hours each day for a period of 10 days. In addition, a standard resting splint was used for the unimpaired hand for an 11-day period. Each patient was encouraged to wear the splint for 90% of his or her waking hours. The following outcome measures were used: the Actual Amount of Use Test (AAUT), the Box and Block Test (BBT), and the upper-extremity grasping and motor portions of the Fugl-Meyer Assessment of Motor Recovery (FM).

OUTCOMES

Immediately after therapy, improvements were found in AAUT and BBT scores, but no improvements were found in FM scores. Three patients underwent brain imaging before and after therapy and showed qualitative changes consistent with reorganization of sensorimotor cortical representations of both paretic and nonparetic hands in one isolated hemisphere.

DISCUSSION

The findings suggest that CIMT may be a feasible method of rehabilitation in individuals with chronic hemiparesis, possibly leading to neuroplastic therapy-related changes in the brain.