Action planning in typically and atypically developing children (unilateral cerebral palsy)

In the present study, we investigated the development of action planning in children with unilateral Cerebral Palsy (CP, aged 3–6 years, n = 24) and an age matched control group. To investigate action planning, participants performed a sequential movement task. They had to grasp an object (a wooden play sword) and place the sword in a hole in a wooden block. Our main dependent variable was the grip type that participants used, i.e., did they adapt their initial grip choice such that they would reach a comfortable posture at the end of the action? This end-state comfort effect has been abundantly shown in research on action planning, and is taken as evidence for anticipatory planning. The first aim of the study was to investigate the development of action planning in the unilateral CP group and the control group. Our hypothesis was that action planning improves with age in the control group, but not in the unilateral CP group. The results showed that planning was impaired in the unilateral CP group compared with the control group. Consistent with our hypothesis, we found an age effect in the control group, but not in the unilateral CP group. In the control group 5 and 6 years olds showed more anticipatory planning compared with the 3 and 4 years olds. The second aim of this study was to examine whether an intervention for children with unilateral CP (i.e., constrained induced movement therapy combined with bimanual training) affected action planning. The children with unilateral CP were therefore measured on the experimental task before and after an 8-week intervention period. The results showed that planning improved after the intervention. This finding suggests that action planning ability in young children with unilateral CP may be sensitive to improvement. These findings are discussed within the context of typical and atypical development of action planning and further guidelines for intervention in children with unilateral CP are given.     

Typical and atypical (cerebral palsy) development of unimanual and bimanual grasp planning

In the present study we tested 13 children with cerebral palsy (CP) and 24 typically developing children (7-12 years old) in a unimanual and bimanual motor planning task. We focused on two research questions: (1) How does motor planning develop in children with and without CP? and (2) Is motor planning facilitated when the task is performed with both hands? Participants had to grasp one or two vertical oriented cylinder(s) and transport it/them to a platform that had different heights. As a measure of motor planning, we registered the height at which participants grasped the cylinder. Here, anticipation of grasp height upon the height of the upcoming target(s) is reflective of proper forward motor planning as it leads to a comfortable posture at the end of the task. In the unimanual task the typically developing children showed a significant grasp height effect, which increased with age. In contrast, no grasp height effect, or age related changes therein were found for the children with CP, suggesting a compromised development of motor planning in these children. Interestingly, when children had to transport one cylinder to a high shelf and one cylinder to a low shelf, the more affected hand of the CP children clearly anticipated the grasp height to the upcoming target height. The less affected hand did not show such anticipation. Taken collectively, these findings suggest a delayed or compromised development of motor planning in children with CP compared to typically developing children. At the same time, the facilitated motor planning of the more affected arm in the bimanual task offers a valuable entry point for intervention to improve motor planning in CP.     

The relationship between unimanual capacity and bimanual performance in children with congenital hemiplegia

Aim This study explores the relationship between unimanual capacity and bimanual performance for children with congenital hemiplegia aged 5 to 16 years. It also examines the relationship between impairments and unimanual capacity and bimanual performance. Method Participants in this cross‐sectional study attended a screening assessment before participating in a large, randomized trial. They comprised 70 children with congenital hemiplegia (39 males, 31 females; mean age 10y 6mo, SD 3y); 18 were classified in the Manual Ability Classification System level I, 51 in level II, and one in level III. Eighteen were in Gross Motor Function Classification System, level I and 52 in level II. Sixty‐five participants had spasticity and five had dystonia and spasticity. Fifteen typically developing children (7 males, 8 females; mean age 8y 8mo, SD 2y 7mo), matched to study participants for age and sex, were recruited as a comparison group for measures of sensation, grip strength, and movement efficiency. Outcome measures for unimanual capacity were the Melbourne Assessment of Unilateral Upper Limb Function (MUUL), and the Jebsen–Taylor Hand Function Test (JTHFT). The Assisting Hand Assessment (AHA) evaluated bimanual performance. Upper limb impairments were measured using assessments of stereognosis, moving two‐point discrimination, spasticity, and grip strength. Results There was a strong relationship between unimanual capacity (MUUL) and bimanual performance (AHA; r=0.83). Linear regression indicated MUUL and stereognosis accounted for 75% of the variance in AHA logit scores. Sensory measures were moderately correlated with unimanual capacity and bimanual performance. Age, sex, and grip strength did not significantly influence bimanual performance. There was no difference between children with right‐ and left‐sided hemiplegia for motor performance. Interpretation Findings of our study confirm a strong relationship between unimanual capacity and bimanual performance in a cohort of children with congenital hemiplegia. However, the directionality of the relationship is unknown and therapists cannot assume improvements in unimanual capacity will lead to gains in bimanual performance.     

Development of hand-arm bimanual intensive training (HABIT) for improving bimanual coordination in children with hemiplegic cerebral palsy

Constraint-induced (CI) movement therapy is a physical intervention that has been receiving increasing attention in pediatric rehabilitation. So far, the evidence suggests that practice associated with CI therapy may improve impaired unimanual hand function in some children with hemiplegic cerebral palsy (CP). However, CI therapy has several important limitations. Most importantly, children with hemiplegia have impairments in bimanual coordination beyond their unilateral impairments. Thus, an intervention approach to increase functional independence during activities of daily living by using both hands in cooperation is needed. Here we briefly review the etiology of hemiplegic CP, describe studies of pediatric CI therapy efficacy in relation to the etiology, discuss the conceptual and practical limitations of CI therapy for this population, and describe bimanual coordination impairments in children with hemiplegia. Finally, we introduce a new intervention for children with hemiplegia, hand-arm bimanual intensive training (HABIT), to address the limitations of CI therapy and to improve bimanual coordination. HABIT retains the two major elements of pediatric CI therapy (intensive structured practice and child-friendliness). The proposed methodology demonstrates that extensive targeted practice can be provided in a child-friendly manner without using a physical restraint, although the efficacy of such an approach remains to be determined.     

Motor learning of a bimanual task in children with unilateral cerebral palsy

Children with unilateral cerebral palsy (CP) have been shown to improve their motor performance with sufficient practice. However, little is known about how they learn goal-oriented tasks. In the current study, 21 children with unilateral CP (age 4–10 years old) and 21 age-matched typically developed children (TDC) practiced a simple bimanual speed stack task over 15 days of practice. Both groups demonstrated their ability to learn the current bimanual task, but their rate of improvement and learning pattern differed. Children with unilateral CP overall were slower and improved ~10% less than TDC. Most of the improvement occurred during the first 3 days for the TDC, whereas performance did not plateau until 6–8 days for the children with unilateral CP. This initial slower learning rate for children with unilateral CP was also confirmed by better fitting of the curve to an exponential function than the power law function (p < 0.05). Therefore, when working with children with unilateral CP, sufficient practice is important (two to three times more than for TDC), and delayed improvement is expected.     

Bimanual Skill Learning after Transcranial Direct Current Stimulation in Children with Unilateral Cerebral Palsy: A Brief Report

ABSTRACT

Bimanual skills are important for goal-oriented activities. Children with unilateral cerebral palsy (UCP) have deficits in unimanual and bimanual motor control and learning. The application of non-invasive brain stimulation with existing motor training may further promote motor learning; however, the effects of stimulation on bimanual learning have not been examined. Here, we assessed the performance of a novel bimanual skill (modified Speed Stacks task) in eight children with UCP before, during, and after a combined motor training and brain stimulation intervention. Participants received 10 days (120 min/day) of goal-oriented bimanual therapy combined initially with transcranial direct current stimulation (tDCS, 20 min/day). Results showed task improvement tapered (p < 0.001) during and after the intervention and task variability decreased in 6/8 participants, indicating the potential impact of novel rehabilitation to improve skill learning in children with UCP. Future work is required to understand how both tDCS and bimanual training contribute to learning bimanual tasks.     

Fingertip forces during object manipulation in children with hemiplegic cerebral palsy. I: anticipatory scaling

Previous studies of grasping and object manipulation in children with cerebral palsy (CP) have suggested a dichotomy in the ability to use anticipatory control (planning) of the fingertip force output, depending on the type of sensory information (tactile or proprioceptive) on which it is based. The present study further explores this issue by testing the ability of 15 children with hemiplegic CP aged between 8 and 14 years to scale the fingertip force output in advance during the lifting of small objects whose weight and surface texture are varied. The results indicate that children with hemiplegia can use anticipatory control based on both the weight and texture of the object, but require a greater number of trials than age-matched children without CP (control children) before they can do so. We suggest that the initial lack of anticipatory control results from an indistinct internal representation of the object's physical properties due to disturbed sensory mechanisms, which may have direct implications for therapeutic intervention.     

Quantitative assessment of mirror movements in children and adolescents with hemiplegic cerebral palsy

Mirror movements in individuals with hemiplegic cerebral palsy (CP) may result from a reorganization of the central sensorimotor system. Motor performances of both hands were measured to characterize mirror activity (or mirroring) and hand functions in 22 participants (6 to 18 years) with hemiplegic CP and in 17 control participants. During a unimanual repetitive squeezing task, contractions of the active hand and fingertip forces of the opposite hand were recorded simultaneously. In the control group, slight mirror activity (or mirroring) was found that decreased with age. In participants with CP, mirror activity was 15 times stronger than in the control group, and was found at all age levels. Mirroring was more prominent in the unaffected hand of the CP group. The amount of mirror activity was not related to the degree of hemiplegia, which was assessed with measures of spasticity, strength, and dexterity. Mirror movements disturbed functional bimanual skills, although to some extent they could be suppressed by voluntary effort.     

Bimanual coordination during a goal-directed task in children with hemiplegic cerebral palsy

Most studies of impaired hand function in children with hemiplegic cerebral palsy (CP) have focused on either the involved or the non-involved extremity in isolation. Coordination of the involved and non-involved hand during bimanual tasks in these children is not well understood. The present study examined bimanual coordination using a drawer-opening task under speed and hand constraints in 10 children with hemiplegic CP (5 males and 5 females, mean age 13y 5mo, range 8y to 16y) and 10 age-matched right-handed developing typically children (6 males and 4 females, mean age 13y 1mo). Children were asked to reach forward and open a drawer with one hand and then activate a light switch inside the drawer with the contralateral hand. The role of the two hands (open drawer and activate switch) and speed (self-paced vs fast-as-possible) were varied. The children with hemiplegic CP were slower (p<0.001) and less coordinated in this task, with reduced movement overlap of the two hands (p<0.001) and sequential completion of the two movement objectives (p<0.001). Moreover, the hand used for each task subcomponent affected task performance for the children with hemiplegic CP (p<0.05). Interestingly, faster speed facilitated better bimanual coordination for the children with hemiplegic CP (p<0.001). Results highlight the importance of movement constraints on task performance and suggest that movement speed might facilitate better bimanual coordination.     

Bimanual behaviours in children aged 8-18 months: a literature review to select toys that elicit the use of two hands

Toys that provoke the use of both hands are required to develop a test of bimanual performance in children 8-18 months with unilateral cerebral palsy (Mini-AHA). To choose the toys, a conceptual model based on perception-action theory and object use was used to guide a literature review. Evidence was sought for three critical relationships identified in the model which help determine bimanual performance: (1) the child-toy relationship, (2) the child-task relationship, and (3) the toy-task relationship. Evidence for both typically developing children and children with unilateral CP in this age range was sought. Thirty-five papers provided information about one or more of the relationships in typically developing children. No evidence was found for children with unilateral CP. Synthesis of the evidence from these three relationships informed toy selection for this new assessment.     

Travail bimanuel versus travail unimanuel chez les enfants (0–18 ans) atteints de paralysie cérébrale spastique unilatérale

ObjectiveThe objective of this work is to research, from the literature, whether there is an interest of bimanual training compared unimanual training in improving the upper limb function in children with unilateral spastic cerebral palsy.MethodPubMed and Science Direct databases have been consulted to find articles since 2000 discussing the intensive bimanual therapy and the constraint induced movement therapy in these patients.ResultsFive articles were selected between 2011 and 2017, including two systematic reviews, a multisite clinical trial, a secondary analysis of a randomized controlled trial and a literature review.ConclusionThe literature shows a strong but nonspecific recommendation for one or the other approach in improving the hemiparetic upper limb function. However, constraint induced movement therapy appears to be more effective in improving grip in the injured hand and there is a weak recommendation for intensive bimanual therapy in improving coordination between limbs and for bimanual activities. The conclusion would be to approach these two therapies by making them complementary and to link unimanual training and bimanual training in the rehabilitation of children with unilateral spastic cerebral palsy.     

Randomized trial of constraint-induced movement therapy and bimanual training on activity outcomes for children with congenital hemiplegia

Aim To determine if constraint‐induced movement therapy (CIMT) is more effective than bimanual training (BIM) in improving upper limb activity outcomes for children with congenital hemiplegia in a matched‐pairs randomized trial. Method Sixty‐three children (mean age 10.2, SD 2.7, range 5–16y; 33 males, 30 females), 16 in Manual Ability Classification System level I, 46 level II, and 1 level III and 16 in Gross Motor Function Classification level I, 47 level II) were randomly allocated to either CIMT or BIM group day camps (60 hours over 10 days). The Melbourne Assessment of Unilateral Upper Limb Function assessed unimanual capacity of the impaired limb and Assisting Hand Assessment evaluated bimanual coordination at baseline, 3 and 26 weeks, scored by blinded raters. Results After concealed random allocation, there was no baseline difference between groups. CIMT had superior outcomes compared with BIM for unimanual capacity at 26 weeks (estimated mean difference [EMD] 4.4, 95% confidence interval [CI] 2.2–6.7; p<0.001). There was no other significant difference between groups post‐intervention. Both groups demonstrated significant improvements in bimanual performance at 3 weeks, with gains maintained by BIM at 26 weeks (EMD 2.3; 95% CI 0.6–4.0; p=0.008). Interpretation Overall, there were only small differences between the two training approaches. CIMT yielded greater changes in unimanual capacity of the impaired upper limb compared with BIM. Results generally reflect specificity of practice, with CIMT improving unimanual capacity and BIM improving bimanual performance. Considerable inter‐individual variation in response to either intervention was evident. Future research should consider serial sequencing unimanual then BIM approaches to optimize upper limb outcomes for children with congenital hemiplegia.     

Relation between clinical measures and fine manipulative control in children with hemiplegic cerebral palsy

The present investigation examines the relation between various clinical measures and the performance of a functional precision grip-lift task. Fifteen children with hemiplegic cerebral palsy (CP), aged 8 to 14 years, and 15 age-matched control children grasped and lifted an object whose surface texture was varied while their fingertip forces were recorded. The force coordination was compared with tactile sensibility, grip strength, manual dexterity, and spasticity using correlational and regression analyses. The findings highlight the importance of tactile sensibility in this task. However, the manner in which sensibility was related varied for the sensory adaptation of fingertip forces, the anticipatory scaling of the force increase, and the smooth transitions between the temporal phases comprising the grip-lift task. The findings also indicate that spasticity affects some measures of the task, but not others, suggesting that the relation between spasticity and motor performance may not be absolute. The results further suggest that the impairments in grasping in children with hemiplegic CP are largely but not exclusively due to disturbed sensory mechanisms which may have direct implications for therapeutic intervention.     

Spontaneous improvement in oculomotor function of children with cerebral palsy

Eye movements are essential to get a clear vision of moving objects. In the present study, we assessed quantitatively the oculomotor deficits of children with cerebral palsy (CP). We recorded eye movements of 51 children with cerebral palsy (aged 5–16 years) with relatively mild motor impairment and compared their performance with age-matched control and premature children. Overall eye movements of children with CP are unexpectedly close to those of controls even though some oculomotor parameters are biased by the side of hemiplegia. Importantly, the difference in performance between children with CP and controls decreases with age, demonstrating that the oculomotor function of children with CP develops as fast as or even faster than controls for some visual tracking parameters. That is, oculomotor function spontaneously improves over the course of childhood. This evolution highlights the ability of lesioned brain of children with CP to compensate for impaired motor function beyond what would be achieved by normal development on its own.     

Efficacy of a hand-arm bimanual intensive therapy (HABIT) in children with hemiplegic cerebral palsy: a randomized control trial

Children with hemiplegic cerebral palsy (CP) have impairments in bimanual coordination above and beyond their unilateral impairments. Recently we developed hand-arm bimanual intensive therapy (HABIT), using the principles of motor learning, and neuroplasticity, to address these bimanual impairments. A single-blinded randomized control study of HABIT was performed to examine its efficacy in children with hemiplegic CP with mild to moderate hand involvement. Twenty children (age range 3 y 6 mo-15 y 6 mo) were randomized to either an intervention (n=10: seven males, three females; mean age 8 y 7 mo, SD 4 y) or a delayed treatment control group (n=10: seven males, three females; mean age 6 y 10 mo, SD 2 y 4 mo). Children were engaged in play and functional activities that provided structured bimanual practice 6 hours per day for 10 days. Each child was evaluated immediately before and after the intervention, and again at 1-month post-intervention. Children in the intervention group demonstrated improved scores on the Assisting Hand Assessment, increased involved extremity use measured using accelerometry and a caregiver survey, bimanual items of the Bruininks-Oseretsky Test of Motor Proficiency, and the simultaneity of completing a draw-opening task with two hands (p<0.05 in all cases). The results suggest that for this carefully selected subgroup of children with hemiplegic CP, HABIT appears to be efficacious in improving bimanual hand use.     

Children with spastic hemiplegia are equally able as controls in maintaining a precise percentage of maximum force without visually monitoring their performance

In this study the hypothesis was tested that children with spastic hemiplegia rely more on externally guided visual feedback when trying to keep force constant with their affected hand (AH) as compared to their non-affected hand (NAH) and as compared to controls. An isometric force task in which a cursor had to be moved to a visually specified target that disappeared half way the task, was performed by 19 children with cerebral palsy (CP), spastic hemiplegia, aged between 5 and 16 years and an aged matched control group. It was found that the absolute deterioration of performance after withdrawal of target visualization did differ between AH, NAH and controls. The absolute error was smaller and the variability was larger in the hemiplegic hand. However, the normalized force error and co-efficient of variation increased similarly between groups. Furthermore, power spectrum density analysis of the force signal showed that both hands in both groups had a similar loss in the energy in the 2-3 Hz range when target visualization was removed. These results suggest that CP children are equally able to produce stable force without visually monitoring their performance than children without CP, provided they are allowed to operate within their own force range.     

Comparing tests of tactile sensibility: aspects relevant to testing children with spastic hemiplegia

Children with hemiplegic cerebral palsy (OP) commonly exhibit tactile sensory deficiencies in their hands in addition to their motor problems. The aim of this study was to compare and evaluate the usefulness of some common tests of tactile sensibility for use with children with hemiplegic CP. Twenty-five children with hemiplegia aged between 5 and 18 years, and 19 control individuals participated. All children were examined with Semmes-Weinstein monofilaments, two-point discrimination (2PD), stereognosis of familiar objects, stereognosis of forms, and functional sensibility. Dexterity, spasticity, and bimanual task performance were also assessed. Results from the different sensory tests deviated greatly. We found three tests to be useful: 2PD of 3 mm spacing, which was the most sensitive test, stereognosis of familiar objects, and functional sensibility assessed through the Pick-up test (comparing performance with and without the influence of vision). Stereognosis of forms and threshold values of touch (Semmes-Weinstein monofilaments) are seemingly less useful tests for children with CNS impairments. Deficient sensibility was strongly related to dexterity. Aspects concerning the testing methodology are discussed.     

Motor learning curve and long-term effectiveness of modified constraint-induced movement therapy in children with unilateral cerebral palsy: A randomized controlled trial

The goal of this study was to determine the progression of manual dexterity during 6 weeks (54 h) (modified) constraint-induced movement therapy ((m)CIMT) followed by 2 weeks (18 h) bimanual training (BiT) in children with unilateral spastic cerebral palsy (CP), to establish whether and when a maximal training effect was reached and which factors might influence the motor learning curve. In addition, long-term retention of effects was determined. In a randomized controlled trial of 52 children with CP, aged 2.5–8 years, comparing mCIMT-BiT to conventional therapy, 28 children were allocated to the mCIMT-BiT group. This group was assessed weekly with the Box and Block test. Long-term effectiveness was determined by collecting follow-up data of the primary (Assisting Hand Assessment, ABILHAND-Kids) and secondary (Melbourne, COPM) outcomes at six months and one year after intervention. Fifteen children (53.6%) reached a maximum training effect within the mCIMT period. This group differed from others with respect to age, but not gender, affected side or manual ability. Children younger than five years had a greater chance to reach a maximum score within 6 weeks mCIMT (OR = 6.67, 95%CI = 1.24–35.71) that stabilized already after four weeks; older children showed a longer progression and tended to decline afterwards. In both age groups, beneficial effects were retained in the long term. The findings suggest that children of 5 years and older might profit from a longer period of mCIMT than 54 h to reach their maximum unimanual capacity and to retain this capacity during subsequent bimanual training.     

Motor planning in children with cerebral palsy: A longitudinal perspective

Introduction: Motor planning is important for daily functioning. Deficits in motor planning can result in slow, inefficient, and clumsy motor behavior and are linked to disruptions in performance of activities of daily living in children with cerebral palsy (CP). However, the evidence in CP is primarily based on cross-sectional data. Method: Data are presented on the development of motor planning in children with CP using a longitudinal design with three measurement occasions, each separated by 1 year. Twenty-two children with CP (9 boys, 13 girls; age in years;months, M = 7;1, SD = 1;2) and 22 age-matched controls (10 boys, 12 girls, M = 7;1, SD = 1;3) participated. Children performed a bar transport task in which some conditions (“critical angles”) required participants to sacrifice initial posture comfort in order to achieve end-state comfort. Performance on critical trials was analyzed using linear growth curve modeling. Results: In general, children with CP showed poor end-state planning for critical angles. Importantly, unlike in controls, motor planning ability did not improve across the three measurement occasions in children with CP. Conclusion: These longitudinal results show that motor planning issues in CP do not resolve with development over childhood. Strategies to enhance motor planning are suggested for intervention.