Matching accuracy in hemiparetic cerebral palsy during unimanual and bimanual movements with (mirror) visual feedback

In the present study participants with Spastic Hemiparetic Cerebral Palsy (SHCP) were asked to match the position of a target either with the impaired arm only (unimanual condition) or with both arms at the same time (bimanual condition). The target was placed at 4 different locations scaled to the individual maximum reaching distance. To test the effect of mirror visual feedback of the less-impaired arm on the matching accuracy, an opaque screen or a mirror was placed in between the arms which masked vision of the impaired arm. Absolute endpoint error was smaller in the bimanual condition compared to the unimanual condition, but there was no effect of mirror visual feedback. Inspection of the individual data, however, showed that 13 out of 23 participants did experience a positive effect of mirror visual feedback. A positive correlation between the baseline error (screen) and the improvement in accuracy with mirror visual feedback seems to suggest that individuals with lower proprioceptive accuracy in the baseline condition may benefit more from mirror visual feedback. Together these findings indicate that bimanual therapy and therapy with mirror visual feedback might be valuable approaches for rehabilitation for a subset of the individuals with SHCP.     

Mirror visual feedback induces lower neuromuscular activity in children with spastic hemiparetic cerebral palsy

The study examined the effects of mirror feedback information on neuromuscular activation during bimanual coordination in eight children with spastic hemiparetic cerebral palsy (SHCP) and a matched control group. The ‘mirror box’ creates a visual illusion, which gives rise to a visual perception of a zero lag, symmetric movement between the two arms. The study incorporated two additional visual feedback conditions by placing a glass or opaque screen between the arms. During bilateral symmetric circular arm movements mirror visual feedback induced lower neuromuscular intensities in the shoulder muscles of the less impaired arm of children with SHCP compared to the other visual conditions. In addition, the mirror lead to shorter relative durations of eccentric and concentric activity in the elbow muscles of the more impaired arm, whereas no effects of visual feedback were found in a matched control group. These results suggest that replacing veridical visual information of the more impaired arm with a mirror reflection of the less impaired arm improves the motor control of children with SHCP during interlimb coupling. The effects of the availability of visual feedback in individuals with hemiparesis are discussed with reference to: (1) increase ipsilateral motor cortex excitability and (2) congruence between afferent (visual) feedback and the internal copy of the motor commands.     

Fast adjustments of ongoing movements in hemiparetic cerebral palsy

The present study focuses on the ability of participants with spastic hemiparesis caused by cerebral palsy to adjust an ongoing movement. Typical symptoms associated with the disorder would lead one to expect that people with spastic hemiparesis would be unable to adjust their movements quickly and proportionally to a sudden change in the environment with their spastic arm. The results of the present experiment, however, prove otherwise. Eight hemiparetic adolescents with cerebral palsy and eight healthy control participants were asked to quickly hit a target projected onto a fronto-parallel screen. The target either remained stationary or started to move immediately after hand movement onset. Participants needed to adapt the ongoing movement to hit moving targets. The task was performed with the spastic and non-spastic arm by the hemiparetic participants and with the dominant arm by the healthy participants. Kinematic analyses showed that although the spastic arm of the hemiparetic participants displayed a significant increase in spatial variability which led to more errors, they were capable of successfully adapting their movement in a qualitative manner. The latency of the response to the change in target position was longer for the hemiparetic participants compared to the healthy control participants, but only 25 ms. Surprisingly, no between arm latency difference was found in the hemiparetic participants. Given the commonly observed movement deficits of the spastic arm, these results show that participants with spastic hemiparesis displayed a remarkable ability in adjusting movements quickly.     

Doing it with mirrors: a case study of a novel approach to neurorehabilitation

Arm amputees can experience the perception of movement of a phantom limb while looking at a mirror reflection of the moving, intact arm superimposed on the perceived phantom. Such use of a mirror to provide illusory visual feedback of movement can be useful in rehabilitation of hemiparetic patients. In this case report, we describe the successful application of "mirror therapy" to the post-stroke rehabilitation of a patient with poor functional use of an upper extremity, due mainly to somatosensory deficits. Mirror therapy facilitated employment of a motor copy strategy (bimanual movements) and later progression to "forced use" of the affected arm. The end result was increased functional use of the affected upper limb.     

Early stages in the acquisition of a bimanual motor skill

Children and adults were trained and tested on a coordinated bimanual task that required them to rotate both hands either at the same or at different angular velocities in order to move the pen of an X-Y recorder along three angles of slant (45, 67 and 22 degrees), and to rotate both hands in the same clockwise direction rather than as mirror image movements. Initially both groups exhibited a tendency to rotate both hands at the same angular velocity even when the task required differential motor output from the two hands. With visual feedback, the tendency toward synchronization, such that both hands moved at the same angular velocity, was asymmetrically distributed, but under blindfolded conditions such asymmetries disappeared. Accuracy of performance increased with practice; and visual feedback enhanced accuracy of performance. The findings suggest that during early stages in the acquisition of a bimanual skill, unintended bilateral coactivation occurs at multiple levels of motor organization; mirror associated movements are only one simple subset of unintentional intermanual synergies.     

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.     

Visual feedback of the non-moving limb improves active joint-position sense of the impaired limb in Spastic Hemiparetic Cerebral Palsy

This study examined the active joint-position sense in children with Spastic Hemiparetic Cerebral Palsy (SHCP) and the effect of static visual feedback and static mirror visual feedback, of the non-moving limb, on the joint-position sense. Participants were asked to match the position of one upper limb with that of the contralateral limb. The task was performed in three visual conditions: without visual feedback (no vision); with visual feedback of the non-moving limb (screen); and with visual feedback of the non-moving limb and its mirror reflection (mirror). In addition to the proprioceptive measure, a functional test [Quality of Upper Extremity Skills Test (QUEST)] was performed and the amount of spasticity was determined in order to examine their relation with proprioceptive ability. The accuracy of matching was significantly influenced by the distance that had to be covered by the matching limb; a larger distance resulted in a lower matching accuracy. Moreover it was demonstrated that static (mirror) visual feedback improved the matching accuracy. A clear relation between functionality, as measured by the QUEST, and active joint-position sense was not found. This might be explained by the availability of visual information during the performance of the QUEST. It is concluded that static visual feedback improves matching accuracy in children with SHCP and that the initial distance between the limbs is an influential factor which has to be taken into account when measuring joint-position sense.     

Immediate effect of a wrist and thumb brace on bimanual activities in children with hemiplegic cerebral palsy

Aim The aim of this study was to determine the immediate effect of wearing a wrist and thumb brace on the performance of bimanual activities in children with spastic hemiplegic cerebral palsy. Method In a pre‐ and post‐test cohort study of 25 children (age range 4–11y; mean age 8y 4mo [SD 2y 2mo]; 16 males, 9 females) with spastic hemiplegic cerebral palsy with a Zancolli classification hand score of I, IIA, or IIB (mild and moderate hand dysfunction; children with a Zancolli classification of III – severe hand dysfunction – were excluded from this study), performance of bimanual activities was evaluated with the Assisting Hand Assessment (AHA) on three occasions: one assessment with a static wrist and thumb brace placed on the affected hand and two other assessments without a brace. The differences between AHA scores obtained at the three assessments were evaluated using the repeated measures analysis of variance. Results Performance of bimanual activities while wearing the brace improved significantly compared to performance without the brace (p<0.001). With the brace, the mean AHA score increased by 3.2 (95% confidence interval 2.1–4.3) from 59.1 to 62.3. The scores of the two assessments without the brace did not differ significantly. Interpretation In children with spastic hemiplegic cerebral palsy, bracing of the wrist and thumb immediately improves spontaneous use of the affected upper limb in bimanual activities, possibly because bracing permits a more functional hand position.     

Bimanual training for children with cerebral palsy: Exploring the effects of Lissajous-based computer gaming

Objective: Hemiplegic cerebral palsy often results in impaired bimanual coordination, partly due to strong coupling between the arms. We aimed at inducing more flexibility in this coupling, to improve bimanual coordination.

Methods: We designed computer games involving simple perceptual goals, based on Lissajous feedback. Such feedback implicitly facilitates the performance of complex rhythmic bimanual coordination patterns. A sample of six children received 9?h of computer training over a 6 weeks period. The effects of this training on functional bimanual performance were explored using the Assisting Hand Assessment (AHA).

Results: Gaming performance and bimanual rhythmic antiphase coordination improved after training. The AHA results were mixed. Two children improved significantly, but at a group level no significant effects were found.

Conclusions: The results were evaluated in relation to the specificity of the AHA and the potential benefit of combining the proposed training with dedicated bimanual functional training programs.     

Deficits in upper limb position sense of children with Spastic Hemiparetic Cerebral Palsy are distance-dependent

This study examined the arm position sense in children with Spastic Hemiparetic Cerebral Palsy (SHCP) and typically developing children (TD) by means of a contralateral matching task. This task required participants to match the position of one arm with the position of the other arm for different target distances and from different starting positions. Results showed that children with SHCP exhibited with both arms larger matching errors than the TD group, but only when the distance between the arms at the start of the movement was large. In addition, the difference in errors between the less-impaired and the impaired limb changed as a function of the distance in the SHCP group whereas no interlimb differences were found in the TD group. Finally, spasticity and restricted range of motion in children with SHCP were not related to the proportion of undershoot and size of absolute error. This suggests that SHCP could be associated with sensory problems in conjunction with their motor problems. In conclusion, the current study showed that accurate matching of the arms is greatly impaired in SHCP when compared to TD children, irrespective of which arm is used. Moreover, this deficit is particularly present for large movement amplitudes.     

The development of anticipatory action planning in children with unilateral cerebral palsy

Background Previous studies suggest that compromised bimanual performance experienced by children with unilateral cerebral palsy (CP) is not only due to difficulties in action execution but may also be a result of impaired anticipatory action planning.Aims The effect of age and side of hemiplegia were examined and the relationship between anticipatory action planning, unimanual capacity and bimanual performance was explored.Methods and procedures Using a multi-centre, prospective, cross-sectional observational design, anticipatory action planning was analyzed in 104 children with unilateral cerebral palsy, aged 6–12 years, using the sword task.Outcomes and results Anticipatory action planning did not improve with age in children with unilateral CP, aged between 6–12 years. No differences were found between children with left or right hemiplegia. Finally, anticipatory action planning was not related to unimanual capacity or bimanual performance.Conclusion and implications This study demonstrates anticipatory action planning, measured using the sword task, does not improve with age in children with unilateral CP and is not related to bimanual performance or laterality. Future studies of anticipatory action planning in children with unilateral CP should consider using measures that require effective anticipatory action planning for successful task completion rather than end state comfort.     

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.     

Book review of The Neuropsychiatry of Epilepsy. Edited by Michael Trimble and Bettina Schmitz (Cambridge,UK: Cambridge University Press, 2002). [Pp. 350]. ISBN 0521005167 (pbk). £39.95.

Bimanual co-ordination is a field that has generated much research interest. It is clear that when hands move simultaneously there is a tendency for such movements to be synchronized. This phenomenon has also been observed in individuals with congenital brain damage, such as cerebral palsy. This paper provides an overview of past and current work in the area of bimanual co-ordination looking at the nature of the coupling and the underlying control of such movements. Work on ‘non-disabled’ individuals and unimanual reaching and grasping is included, but the main emphasis is bimanual co-ordination in children with hemiparetic cerebral palsy. The direction for future research is discussed and consideration given to the therapeutic implications of such work.     

Pathophysiology of gait in children with cerebral palsy

The surface electromyogram (EMG) of leg muscles was recorded together with the changes of the angle at the ankle joint during slow gait in 10 normal children and 10 with cerebral palsy. The characteristic pattern of muscle activity recorded from the spastic legs mainly consisted of a co-activation of antagonistic leg muscles during the stance phase of a gait cycle and a general reduction in amplitude of EMG activity. The tension of the Achilles tendon, measured in 2 hemiparetic children during gait, increased much more steeply in the spastic leg than in the normal one at the beginning of the stance phase, when the electrically almost silent triceps surae was stretched. It is suggested that muscle hypertonia during gait in spastic children is mainly due to changed muscle fibre mechanical properties, as recently discussed also for spastic adults. While in the latter the reciprocal EMG activity of antagonistic leg muscles was preserved it is proposed that muscle co-activation recorded in spastic children is due to an impaired maturation of the locomotor pattern with an early neuronal adaptation to altered muscle fibre mechanical characteristics.     

Effect of Task on Movement Control in Cerebral Palsy: Implications for Assessment and Therapy

In order to examine the possibility that children with cerebral palsy (CP) find abstract tasks, such as extending the arm as much as possible, more difficult than concrete tasks, such as reaching to grasp an object, nine hemiparetic children with CP and 12 nursery-school children were tested with both a concrete and an abstract task. The children with CP achieved a significantly larger range of movement in the concrete task, whereas the nursery-school children showed no difference between tasks. Thus the CP children's poorer performance on the abstract task did not fully reflect their movement capability. This means that conventional neurological measurements of limb function in cerebral palsy, which mainly use abstract tasks or passive movements, will give an incomplete picture of the child's action capability.     

Learning to cope with mirror movements in unilateral spastic cerebral palsy: a brief report

ABSTRACT

Purpose: Mirror movements (MM) in unilateral spastic cerebral palsy (USCP) interfere with many bimanual activities of daily living.

Methods: Here, we developed a specific bimanual therapeutic regimen, focusing on asymmetric simultaneous movements of the two hands. Twelve children (6-17 years old; complete data available in ten children) with USCP and MM were included.

Results: After three weeks of inpatient rehabilitation, we observed significant improvements for two self-defined bimanual goal activities (Goal Attainment Scaling, Canadian Occupational Performance Measure) and for bimanual performance in general (Assisting Hand Assessment). These improvements were still present 6 months later. In contrast, even immediately after therapy, the severity of MM had not changed.

Conclusions: Hence, targeted bimanual therapy improved bimanual performance, but did not lead to a reduction of MM. The results of this pilot study might suggest that children with MM benefit more from acquiring strategies to cope with MM than by an active training which aimed to reduce MM.     

Comparisons of right and left hemiparetic cerebral palsy

The purpose of this study was to compare right and left hemiparetic cerebral palsy. Sixty children (34 males, 26 females) with hemiparetic cerebral palsy were recruited. Thirty-two children manifested left hemiparetic cerebral palsy and 28 right hemiparetic cerebral palsy. Low birth weight, seizures, a family history of epilepsy, severity of cerebral palsy, and computed tomographic findings were analyzed. No significant differences were found between the clinical patterns of hemiparesis in both groups. Gestational history, low birth weight, and perinatal pathologies were present in similar percentages in the left and the right hemiparetic cerebral palsy children. Significantly greater numbers of pregnancies (P = 0.003) and deliveries (P = 0.01) were observed in the left hemiparetic cerebral palsy group as compared with the right hemiparetic cerebral palsy group. Similarly, significantly (P = 0.03) lower values of the Apgar score were recorded in the left hemiparetic cerebral palsy group than the right hemiparetic cerebral palsy group. A similar percentage of neuroradiologic abnormalities was detected in both groups. Twenty-six (43.3%) children with hemiparetic cerebral palsy had epilepsy. The incidence of intractable epilepsy was similar in both groups. The results of this study are comparable with earlier reports on hemiparetic cerebral palsy.     

The early markers for later dyskinetic cerebral palsy are different from those for spastic cerebral palsy

Qualitative abnormalities of spontaneous motor activity in newborns and young infants are early predictive markers for later spastic cerebral palsy. Aim of this research was to identify which motor patterns may be specific for later dyskinetic cerebral palsy. In a large, prospectively performed longitudinal study involving four European hospitals we identified twelve cases with the relatively rare condition of dyskinetic cerebral palsy and compared their early motor development with twelve spastic cerebral palsy cases and twelve controls. From birth to the fifth month post-term, all infants were repeatedly videoed and their spontaneous motor patterns, including general movements, were assessed. Until the second month post-term, the infants that later became dyskinetic displayed a poor repertoire of general movements, "arm movements in circles" and finger spreading. Abnormal arm and finger movements remained until at least five months and were then concurrent with a lack of arm and leg movements towards the midline. Later dyskinetic infants share with later spastic infants the absence of fidgety movements, a spontaneous movement pattern that is normally present from three to five months. Qualitative assessment of spontaneous motor patterns enabled us to identify infants at high risk for dyskinetic cerebral palsy early in life. Additionally, we were able to discriminate them from those infants at high risk for later spastic cerebral palsy. This is a matter of significant clinical relevance because the two types of cerebral palsy ask for different management and early intervention.     

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.     

Somatosensory evoked potentials in children with bilateral spastic cerebral palsy

Alterations were monitored of somatosensory evoked potentials in children with bilateral spastic cerebral palsy and these findings correlated with relevant clinical and laboratory parameters. Fifty-one children with bilateral spastic cerebral palsy (31 boys, 20 girls; age range 24-168 months) participated in the study. Abnormal somatosensory evoked potentials latencies were recorded in 23 of 34 (67.6%) cortical recordings of the median nerve and in 38 of 51 (74.5%) cortical recordings of the tibial nerve. Abnormal tibial nerve somatosensory evoked potentials were strongly correlated with abnormal electroencephalogram (P=0.014), while impaired median nerve recordings were correlated with abnormal visual evoked potentials (P = 0.02) and a history of perinatal or neonatal infection (P=0.016). Furthermore, perinatal/neonatal infection adversely effected the recordings in both tibial and medial nerves in quadriplegic patients (P=0.023). Sensory impairment is strongly related with abnormal visual evoked potentials, abnormal electroencephalogram, and a history of perinatal or neonatal infection.