Quantitative diffusion tensor tractography of the motor and sensory tract in children with cerebral palsy

Aim The aim of this study was to compare the findings of quantitative diffusion tensor tractography of the motor and sensory tracts in children with cerebral palsy (CP) and typically developed comparison individuals, and also to evaluate the correlation with gross motor function. Method Thirty‐four children with CP (mean age 2y 2.mo, SD 2y 0mo; 19 with spastic diplegia, eight with hemiplegia, six with spastic quadriplegia, and one with spastic triplegia) and 21 healthy comparison children (mean 2y 1.68mo, SD 2y 8.64mo) were evaluated. The distribution of Gross Motor Function Classification System (GMFCS) levels in the CP group was as follows: level I, 7; level II, 14; level III, 5; level IV, 3; and level V, 5. The following three diffusion tensor imaging (DTI) parameters including tractography were evaluated for each tract (corticospinal tract [CST] and posterior thalamic radiation [PTR]): number of fibres, tract‐based fractional anisotropy, and region of interest (ROI)‐based fractional anisotropy. We compared each value between the two groups, and correlated each value with the GMFCS level. Results The number of fibres and ROI‐based fractional anisotropy values of both tracts were significantly lower in children with CP than in the comparison group (p<0.05–0.001). Additionally, there was significant negative correlation between GMFCS level and motor–sensory parameters (p<0.001–0.05). Interpretation DTI parameters of the CST and PTR in children with CP were significantly lower than in comparison children. In addition, these parameters were significantly correlated with GMFCS level.     

Relationship between gross motor capacity and daily‐life mobility in children with cerebral palsy

Aim The aim of this study was to examine the relationship between gross motor capacity and daily‐life mobility in children with cerebral palsy (CP) and to explore the moderation of this relationship by the severity of CP. Method Cross‐sectional analysis in a cohort study with a clinic‐based sample of children with CP (n=116; 76 males, 40 females; mean age 6y 3mo, SD 12mo, range 4y 8mo–7y 7mo) was performed. Gross motor capacity was assessed by the Gross Motor Function Measure (GMFM‐66). Daily‐life mobility was assessed using the Pediatric Evaluation of Disability Inventory (PEDI): Functional Skills Scale (FSS mobility) and Caregiver Assistance Scale (CAS mobility). Severity of CP was classified by the Gross Motor Function Classification System (48% level I, 17% level II, 15% level III, 8% level IV, 12% level V), type of motor impairment (85% spastic, 12% dyskinetic, 3% ataxic), and limb distribution (36% unilateral, 49% bilateral spastic). Results Scores on the GMFM‐66 explained 90% and 84% respectively, of the variance of scores on PEDI‐FSS mobility and PEDI‐CAS mobility. Limb distribution moderated the relationship between scores on the GMFM‐66 and the PEDI‐FSS mobility, revealing a weaker relationship in children with unilateral spastic CP (24% explained variance) than in children with bilateral spastic CP (91% explained variance). Interpretation In children aged 4 to 7 years with unilateral spastic CP, dissociation between gross motor capacity and daily‐life mobility can be observed, just as in typically developing peers.     

Drooling in cerebral palsy: hypersalivation or dysfunctional oral motor control?

Aim  To investigate whether drooling in children with cerebral palsy (CP) in general and in CP subtypes is due to hypersalivation.
Method  Saliva was collected from 61 healthy children (30 males, mean age 9y 5mo [SD 11mo]; 31 females, mean age 9y 6mo [1y 2mo]) and 100 children with CP who drooled (57 males, mean age 9y 5mo [3y 11mo], range 3–19y; 43 females, mean age 10y 1mo [4y 9mo], range 4–19y), of whom 53 had spastic, 42 had dyskinetic, and five had ataxic CP. Almost all children were affected bilaterally, and 90 of them were at Gross Motor Function Classification System levels III or higher. The saliva was collected by the swab saliva collection method. The intensity of drooling was evaluated using the drooling quotient.
Results  No difference was found in the flow rates, age, or sex between healthy children and children with CP who drooled. On additional subgroup analysis, the flow rates of children with dyskinetic CP differed statistically from those of healthy children (submandibular p =0.047, parotid p =0.040).
Interpretation  This study supports the finding in previous studies that no hypersalivation exists in children with CP who drool. Dysfunctional oral motor control seems to be responsible for saliva overflow from the mouth, whereas increased unstimulated salivary flow may occur in children with dyskinetic CP as a result of hyperkinetic oral movements.     

Neuroimpairments, activity performance, and participation in children with cerebral palsy mainstreamed in elementary schools

Participation and activity performance (motor and cognitive or behavioural) were examined in 148 children with cerebral palsy (CP; 87 males, 61 females; mean age 9y 8mo, SD 1y 11mo; range 6y 1mo to 13y 7mo), mainstreamed in fully inclusive (n=100) and in self-contained classes (n=48) within general schools in Israel, using the School Function Assessment. Differences in participation within these groups were analyzed in relation to the type of CP (mainly spastic hemiplegia, spastic diplegia, and spastic tetraplegia), the level of impairment according to the Gross Motor Function Classification System (GMFCS; level II 55%, level III 37%, and level IV 8%), and additional neuroimpairments. Univariate analyses of variance revealed significant differences in levels of participation and levels of activity performance between different types of CP and GMFCS levels. With regard to additional neuroimpairments, significant differences in participation were found for fully included children with speech and language impairments and those with learning disability within the self-contained group. Physical activity performance partly accounted for differences in participation between children with different types of CP and different levels of motor impairment. These findings suggest that within the mainstreamed environment, participation and activity performance increase as motor disability and/or additional neuroimpairments (speech and language impairments and learning disability) decrease.     

Does sex influence outcome in ambulant children with bilateral spastic cerebral palsy?

To investigate the effect of sex on the phenotype of bilateral spastic cerebral palsy (CP) we reviewed the gait analysis data of 116 children (78 males, mean age 8 y 1 mo [SD 3 y 1 mo] and 38 females, mean age 8 y 9 mo [3 y 1 mo]) with bilateral spastic CP (Gross Motor Function Classification System [GMFCS] Levels I [four males, six females]; II [41 males, 19 females]; III [26 males, 12 females]; and IV [7 males, 1 female]) who had been referred for gait analysis to inform treatment. Although there were no differences between males and females in terms of gestational age, chronological age, or GMFCS level, males were more likely to have had nonoperative intervention before the referral (p=0.024), had a greater degree of knee flexion in stance phase when walking (p=0.003), and had a higher Gillette Gait Index (p<0.001) when compared with females. Males were also more likely to have surgery recommended on the basis of gait analysis (p<0.001). Sex seems to influence the development of the musculoskeletal system and mobility in ambulant children with bilateral spastic CP, and this may need to be considered when planning intervention or when assessing the outcome of intervention.     

The impact of botulinum toxin A and abduction bracing on long-term hip development in children with cerebral palsy

Aim To study the long‐term impact of 3 years of botulinum toxin A (BoNT‐A) injections and abduction bracing on hip development in children with bilateral spastic cerebral palsy (CP). We wanted to know if early treatment improved hip development and reduced the need for surgery. Method A long‐term review of hip morphology and surgery requirements in children who participated in a multicentre, randomized controlled trial. The trial investigated short‐term effects of BoNT‐A injections combined with an abduction brace, compared with usual care, on hip displacement in children with bilateral spastic CP. Results Forty‐six children with bilateral spastic CP (31 males, 15 females; 10 with diplegia, 36 with quadriplegia; mean age at enrolment of 3y 2mo, mean age at most recent clinical review 13y 11mo [range 10y 6mo–16y 8mo]; three children in Gross Motor Function Classification System level II, 11 in level III, 20 in level IV, 12 in level V) were followed for a mean of 10 years 10 months from recruitment to the trial. Mean migration percentage was 15.9% in the BoNT‐A group and 15.2% in the comparison group (t=0.26, p=0.79). Eighty‐nine percent of hips in the treatment group and 91% hips in the comparison group had satisfactory development, using a valid scale (Mann–Whitney U test=867.50, z=?1.59, p=0.11). Forty children had preventive surgery (21 treatment group, 19 comparison group) and 18 children had reconstructive surgery (10 treatment, 8 comparison). Interpretation In children with bilateral spastic CP, early treatment with BoNT‐A and hip abduction bracing does not reduce the need for surgery or improve hip development at skeletal maturity.     

Stability of the Gross Motor Function Classification System after single‐event multilevel surgery in children with cerebral palsy

Aim There are conflicting reports about the stability of the Gross Motor Function Classification System (GMFCS) in children with cerebral palsy (CP) after orthopaedic surgery. We studied the stability of the GMFCS in children with bilateral spastic CP after single‐event multilevel surgery, using the Gait Profile Score (GPS) as the primary outcome measure. Method This was a retrospective cohort study of 107 children (46 females, 61 males) with bilateral spastic CP, classified as GMFCS level II or III, who underwent surgery at a single tertiary institution between 1997 and 2008. The mean age at surgery was 10 years 7 months (SD 2y 8mo). The primary outcome measure was the GPS. Changes in GMFCS level were studied at multiple time points before and after intervention. Results Gait dysfunction was partially corrected, with a mean improvement of 28% in the GPS. The GMFCS remained stable and unchanged in 95% of children and improved by one level in 5% of children. The improvement in GPS was three times the minimal clinically important difference. The mean age at final postoperative GPS assessment was 11 years 10 months (SD 2y 10mo) and at final GMFCS assessment was 15 years 7 months (SD 3y 9mo). Interpretation Stability of the GMFCS was confirmed in the majority of children with bilateral spastic CP after single‐event multilevel surgery, despite statistically and clinically significant improvements in gait dysfunction and functional mobility. This information is important in realistic goal‐setting and in counselling families.     

Oromotor dysfunction and communication impairments in children with cerebral palsy: a register study

Aim To report the prevalence, clinical associations, and trends over time of oromotor dysfunction and communication impairments in children with cerebral palsy (CP). Method Multiple sources of ascertainment were used and children followed up with a standardized assessment including motor speech problems, swallowing/chewing difficulties, excessive drooling, and communication impairments at age 5 years. Results A total of 1357 children born between 1980 and 2001 were studied (781 males, 576 females; median age 5y 11mo, interquartile range 3–9y; unilateral spastic CP, n=447; bilateral spastic CP, n=496; other, n=112; Gross Motor Function Classification System [GMFCS] level: I, 181; II, 563; III, 123; IV, 82; IV, 276). Of those with ‘early‐onset’ CP (n=1268), 36% had motor speech problems, 21% had swallowing/chewing difficulties, 22% had excessive drooling, and 42% had communication impairments (excluding articulation defects). All impairments were significantly related to poorer gross motor function and intellectual impairment. In addition, motor speech problems were related to clinical subtype; swallowing/chewing problems and communication impairments to early mortality; and communication impairments to the presence of seizures. Of those with CP in GMFCS levels IV to V, a significant proportion showed a decline in the rate of motor speech impairment (p=0.008) and excessive drooling (p=0.009) over time. Interpretation These impairments are common in children with CP and are associated with poorer gross motor function and intellectual impairment.     

Self‐care and mobility skills in children with cerebral palsy,related to their manual ability and gross motor function classifications

Aim The aim of this study was to investigate the acquisition of self‐care and mobility skills in children with cerebral palsy (CP) in relation to their manual ability and gross motor function. Method Data from the Pediatric Evaluation of Disability Inventory (PEDI) self‐care and mobility functional skill scales, the Manual Ability Classification System (MACS), and the Gross Motor Function Classification System (GMFCS) were collected from 195 children with CP (73 females, 122 males; mean age 8y 1mo; SD 3y 11mo; range 3–15y); 51% had spastic bilateral CP, 36% spastic unilateral CP, 8% dyskinetic CP, and 3% ataxic CP. The percentage of children classified as MACS levels I to V was 28%, 34%, 17%, 7%, and 14% respectively, and classified as GMFCS levels I to V was 46%, 16%, 15%, 11%, and 12% respectively. Results Children classified as MACS and GMFCS levels I or II scored higher than children in MACS and GMFCS levels III to V on both the self‐care and mobility domains of the PEDI, with significant differences between all classification levels (p<0.001). The stepwise multiple regression analysis verified that MACS was the strongest predictor of self‐care skills (66%) and that GMFCS was the strongest predictor of mobility skills (76%). A strong correlation between age and self‐care ability was found among children classified as MACS level I or II and between age and mobility among children classified as GMFCS level I. Many of these children achieved independence, but at a later age than typically developing children. Children at other MACS and GMFCS levels demonstrated minimal progress with age. Interpretation Knowledge of a child’s MACS and GMFCS level can be useful when discussing expectations of, and goals for, the development of functional skills.     

Relation between physical fitness and gross motor capacity in children and adolescents with cerebral palsy

Aim  To examine the relation between physical fitness and gross motor capacity in children with cerebral palsy (CP) who were classified in Gross Motor Function Classification System levels I or II.
Method  In total, 68 children with CP (mean age 12y 1mo, SD 2y 8mo; 44 males, 24 females; 45 classified as having spastic unilateral CP, 23 as having spastic bilateral CP) participated in this study. All participants performed a maximal aerobic exercise test (10m Shuttle Run Test), a short-term muscle power test (Muscle Power Sprint Test), an agility test (10×5m sprint test), and a functional muscle strength test (30s repetition maximum) within 2 weeks. Gross motor capacity was concurrently assessed using dimensions D (standing) and E (walking, running, and jumping) of the 88-item version of the Gross Motor Function Measure (GMFM).
Results  No relation between aerobic capacity, body mass index, and dimensions D and E of the GMFM was found. The correlations between short-term muscle power, agility, functional muscle strength, and dimensions D and E of the GMFM were moderate to high ( r ∼0.6–0.7).
Interpretation  The relations found between short-term muscle power, agility, functional muscle strength, and gross motor capacity indicate the importance of these components of physical fitness, and may direct specific interventions to maximize gross motor capacity in children and adolescents with CP.     

Ambulatory activity of children with cerebral palsy: which characteristics are important?

Aim To assess ambulatory activity of children with cerebral palsy (CP), aged 7 to 13 years, and identify associated characteristics. Method Sixty‐two children with spastic CP (39 males, 23 females; mean age 10y 1mo, SD 1y 8mo; age range 7–13y), classified as Gross Motor Function Classification System (GMFCS) levels I to III, participated. Ambulatory activity was measured during 1 week with a StepWatch activity monitor as steps per day, and time spent at medium and high step rates. Multiple linear regression analyses were performed following a backward selection procedure until only independent variables with p<0.05 remained in the model. Ambulatory activity outcome parameters served as dependent variables, and disease, personal, and environmental characteristics as independent variables. Ambulatory activity was corrected for body height. Results Children took more steps during school days (5169 steps, SD 1641) than during weekend days (4158 steps, SD 2048; p<0.001). Higher GMFCS level, bilateral CP, and higher age were associated with lower ambulatory activity on school days (R² ranged from 43–53%), whereas bilateral CP, higher age, and no sport club participation were associated with lower ambulatory activity in the weekend (R² ranged from 21–42%). Correcting for body height decreased the association with age. Interpretation Interventions should focus at increasing physical activity at the weekend for children with bilateral spastic CP.     

Hyperactive stretch reflexes, co-contraction, and muscle weakness in children with cerebral palsy

The aim of this study was to examine the repeatability of and relationships among spasticity, co-contraction of agonist–antagonist, and muscle strength in children with cerebral palsy (CP). Eight children with spastic diplegic CP (five males, three females; Gross Motor Function Classification System [GMFCS] Levels I–III; mean age 10y 2mo [SD 2y 9mo], range 6–13y) and nine children in a comparison group (six males, three females; mean age 8y 10mo [SD 2y 4mo], range 6y to 12y 6mo) were assessed twice to examine repeatability of Composite Spasticity Scale, soleus stretch reflexes, electromyography (EMG) co-contraction ratio, and torque recorded during maximal isometric voluntary contraction of ankle dorsiflexors and plantarflexors. Sixty-one children with spastic CP, (54 diplegic, seven hemiplegic; 32 males, 29 females; GMFCS levels I–III; mean age 10y 8mo [SD 2y 9mo], range 6–15y) were then assessed to delineate possible correlations among these measures. Intraclass correlation coefficients (0.78–0.97) showed high data repeatability in both groups. Children with spastic CP demonstrated significantly larger soleus stretch reflex/M-response areas smaller torques, but larger EMG co-contraction ratios during both voluntary dorsiflexion and plantarflexion (all p <0.05). Children with spastic CP who had larger soleus stretch reflex/M-response areas demonstrated larger plantarflexion co-contraction ratio ( r = 0.28), and produced smaller plantarflexion and dorsiflexion torques ( r = –0.48 and –0.27 respectively). However, no correlation was noted between soleus stretch reflex and clinical spasticity. Our findings demonstrated that hyperactive soleus stretch reflex affected torque production of ankle muscles. Moreover, the severity of spasticity may not be fully described by either stretch reflex or tone measure alone.     

Gross motor functional abilities in preterm-born children with cerebral palsy due to periventricular leukomalacia

To describe the impact of periventricular leukomalacia (PVL) on gross motor function, data on 59 children (37 males, 22 females) with a gestational age (GA) of 34 weeks or less with cerebral palsy (CP) due to PVL grade I (n=20), II (n=13), III (n=25), and IV (n=1) were studied; (mean GA 29 wk 4d [SD 4 wk 6d]; mean birthweight 1318 g [SD 342]). Two independent raters used the Gross Motor Function Classification System (GMFCS) at four time points: T1, mean corrected age (CA) 9 months 15 days (SD 2 mo 6d); T2, mean CA 16 months (SD 1 mo 27 d); T3, mean CA 24 months 27 days (SD 2 mo 3d); and T4, median age 7 years 6 months (range 2 y 2 mo-16 y 8 mo). Interrater reliability and stability across time with respect to the total cohort were kappa>or=0.86 and rho>or=0.74 respectively. The association between PVL and gross motor outcome at T4 was strong (positive and negative predictive values 0.92 and 0.85 respectively). The proportion of children who remained in the same GMFCS level increased from 27% (T1-T4) to 53% (T2-T4) and 72% (T3-T4). PVL grade I to II, as diagnosed in the neonatal period, has a better functional mobility prognosis than PVL grade III-IV. These findings have implications for habilitation counselling and intervention strategies.     

Gait adaptation of children with cerebral palsy compared with control children when stepping over an obstacle

This study investigated the adaptive gait pattern in obstacle clearance in 12 normally developing (ND) children (six males, six females; mean age 10y 2mo, SD 10mo) and 12 children who had spastic diplegic cerebral palsy (CP) and who were independent ambulators (10 males, two females; mean age 13y 5mo, SD 2y 7mo). Children in both groups had 8 to 12 years of walking experience. They walked up to and crossed over obstacles of a height of 0%, 10%, and 20% of their leg length. Kinematic aspects of the three-dimensional leg movements were captured with the Vicon system and analyzed with one-way analysis of variance with repeated measure. Both groups increased foot clearance for higher obstacles. Children with CP were slower in approach and crossing speed, and used a wider base of support than the ND children when the obstacle height was increased. Results suggest that motor problems in obstacle clearance in children with CP lie in the implicit process of motor control, i.e. torque dynamics, not the explicit process, i.e. movement-match with the environmental constraints.     

Passive muscle properties are altered in children with cerebral palsy before the age of 3 years and are difficult to distinguish clinically from spasticity

Aim

Clinical determination of spasticity is confounded by the difficulty in distinguishing reflex from passive contributions to muscle stiffness. There is, therefore, a risk that children with cerebral palsy (CP) receive antispasticity treatment unnecessarily. To investigate this, we aimed to determine the contribution of reflex mechanisms to changes in the passive elastic properties of muscles and tendons in children with CP.

Method

Biomechanical and electrophysiological measures were used to determine the relative contribution of reflex and passive mechanisms to ankle muscle stiffness in 35 children with spastic CP (21 males, 14 females; mean age 9y, SD 3y 4mo; range 3–15y) and 28 control children without CP (19 males, nine females; mean age 8y 11mo, SD 2y 10mo; range 3–15y). Twenty‐seven children were diagnosed as having spastic hemiplegia, six with spastic diplegia, and two with spastic tetraplegia. According to the Gross Motor Function Classification System, 31 children were classified in level I, two in level II, and two in level III.

Results

Only seven children with spastic CP showed reflex stiffness outside the range of the control children. In contrast, 20 children with spastic CP showed abnormal passive muscle stiffness (p<0.001). No correlation between increased reflex or increased passive muscle stiffness and age was observed within the age range studied.

Interpretation

These data suggest that increased reflex‐mediated muscle stiffness is difficult to distinguish clinically from changes in passive muscle stiffness and that signs of changes in muscle properties are already present from the age of 3 years in children with CP. This emphasizes the importance of accurately distinguishing different contributions to muscle stiffness to avoid unnecessary antispasticity treatment.     

Sensory and motor deficits in children with cerebral palsy born preterm correlate with diffusion tensor imaging abnormalities in thalamocortical pathways

Aim  Cerebral palsy (CP) is frequently linked to white matter injury in children born preterm. Diffusion tensor imaging (DTI) is a powerful technique providing precise identification of white matter microstructure. We investigated the relationship between DTI-observed thalamocortical (posterior thalamic radiation) injury, motor (corticospinal tract) injury, and sensorimotor function.
Method  Twenty-eight children born preterm (16 males, 12 females; mean age 5y 10mo, SD 2y 6mo, range 16mo–13y; mean gestational age at birth 28wks, SD 2.7wks, range 23–34wks) were included in this case–control study. Twenty-one children had spastic diplegia, four had spastic quadriplegia, two had hemiplegia, and one had ataxic/hypotonic CP; 15 of the participants walked independently. Normative comparison data were obtained from 35 healthy age-matched children born at term (19 males, 16 females; mean age 5y 9mo, SD 4y 4mo, range 15mo–15y). Two-dimensional DTI color maps were created to evaluate 26 central white matter tracts, which were graded by a neuroradiologist masked to clinical status. Quantitative measures of touch, proprioception, strength (dynamometer), and spasticity (modified Ashworth scale) were obtained from a subset of participants.
Results  All 28 participants with CP had periventricular white-matter injury on magnetic resonance imaging. Using DTI color maps, there was more severe injury in the posterior thalamic radiation pathways than in the descending corticospinal tracts. Posterior thalamic radiation injury correlated with reduced contralateral touch threshold, proprioception, and motor severity, whereas corticospinal tract injury did not correlate with motor or sensory outcome measures.
Interpretation  These findings extend previous research demonstrating that CP in preterm children reflects disruption of thalamocortical connections as well as descending corticospinal pathways.     

Brain magnetic resonance imaging and motor and intellectual functioning in 86 patients born at term with spastic diplegia

Aim To investigate the association between magnetic resonance imaging (MRI) patterns and motor function, epileptic episodes, and IQ or developmental quotient in patients born at term with spastic diplegia. Method Eighty‐six patients born at term with cerebral palsy (CP) and spastic diplegia (54 males, 32 females; median age 20y, range 7–42y) among 829 patients with CP underwent brain MRI between 1990 and 2008. The MRI and clinical findings were analysed retrospectively. Intellectual disability was classified according to the Enjoji developmental test or the Wechsler Intelligence Scale for Children (3rd edition). Results The median ages at diagnosis of CP, assignment of Gross Motor Function Classification System (GMFCS) level, cognitive assessment, and MRI were 2 years (range 5mo–8y), 6 years (2y 8mo–19y), 6 years (1y 4mo–19y), and 7 years (10mo–30y) respectively. MRI included normal findings (41.9%), periventricular leukomalacia, hypomyelination, and porencephaly/periventricular venous infarction. The frequency of patients in GMFCS levels III to V and intellectual disability did not differ between those with normal and abnormal MRI findings. Patients with normal MRI findings had significantly fewer epileptic episodes than those with abnormal ones (p=0.001). Interpretation Varied MRI findings, as well as the presence of severe motor dysfunction and intellectual disability (despite normal MRI), suggest that patients born at term with spastic diplegia had heterogeneous and unidentified pathophysiology.     

Comparison of efficacy of Adeli suit and neurodevelopmental treatments in children with cerebral palsy

This study compared the efficacy of Adeli suit treatment (AST) with neurodevelopmental treatment (NDT) in children with cerebral palsy (CP). Twenty-four children with CP, Levels II to IV according to the Gross Motor Function Classification System (GMFCS), were matched by age and functional status and randomly assigned to the AST or NDT treatment groups. In the AST group (n=12; eight males, four females; mean age 8.3 y [SD 2.0]), six children had spastic/ataxic diplegia, one triplegia and five spastic/mixed quadriplegia. In the NDT group (n=12; nine males, three females; mean age 8.1 y [SD 2.2]), five children had spastic diplegia and seven had spastic/mixed quadriplegia. Both groups were treated for 4 weeks (2 hours daily, 5 days per week, 20 sessions). To compare treatments, the Gross Motor Function Measure (GMFM-66) and the mechanical efficiency index (EIHB) during stair-climbing were measured at baseline, immediately after 1 month of treatment, and 10 months after baseline. The small but significant time effects for GMFM-66 and EIHB that were noted after 1 month of both intensive physiotherapy courses were greater than expected from natural maturation of children with CP at this age. Improvements in motor skills and their retention 9 months after treatment were not significantly different between the two treatment modes. Post hoc analysis indicated a greater increase in EIHB after 1 month (p=0.16) and 10 months (p=0.004) in AST than that in NDT, predominantly in the children with higher motor function (GMFCS Levels II and III). The results suggest that AST might improve mechanical efficiency without a corresponding gain in gross motor skills, especially in children with higher levels of motor function.     

Synergistic muscle activation during maximum voluntary contractions in children with and without spastic cerebral palsy

We examined muscle recruitment patterns in children with cerebral palsy (CP) and comparison children without CP under conditions of maximum voluntary contractions. Three groups of children participated in the study: (1) 12 children with diplegic CP (eight males, four females; age range 4-10 y, mean age 7 y [SD 2 y 4 mo]); (2) six children with hemiplegic CP (four males, two females; age range 5-10 y, mean age 7 y 4 mo [SD 2 y]); and (3) 13 comparison children with normal motor function (seven males, six females; age range 4-11 y, mean age 7 y 2 mo, [SD 2 y]). The children with CP were classified according to the Gross Motor Function Classification System: eight were Level I, five were Level II, four were Level III, and one was Level IV. Surface electromyography was recorded from four proximal and distal lower extremity (LE) muscles. Children with CP more frequently activated a muscle other than the intended prime mover first, compared with the comparison children, especially when the prime mover was a distal muscle. For example, during ankle plantar flexion, when the lateral gastrocnemius muscle was the prime mover, children with hemiplegia showed preactivation of the tibialis anterior muscle and children with diplegia showed medial hamstring coactivation. In conclusion, children with CP showed considerable differences to the comparison children in how LE muscles were voluntarily activated. Greater understanding of muscle recruitment patterns under a variety of tasks may provide new directions for motor control retraining or other forms of intervention.     

Participation and enjoyment of leisure activities in school-aged children with cerebral palsy

The objective of this study was to characterize participation in leisure activities in children with cerebral palsy (CP) and identify determinants of greater involvement. Ninety-five children of school age (9y 7mo [SD 2y 1mo]) with CP were recruited, and participation was evaluated with the Children's Assessment of Participation and Enjoyment in a subset (67/95; 42 males, 25 females) who could actively participate in completion of the assessment. Most had mild motor dysfunction (Gross Motor Function Classification System: 59% level I, 23% level II, 18% levels III-V) and had a spastic subtype of CP (23 hemiplegia, 17 diplegia, 16 quadriplegia, 11 other). Biomedical, child, family and environmental predictor variables were considered in the analysis. Results demonstrated that these children were actively involved in a wide range of leisure activities and experienced a high level of enjoyment. However, involvement was lower in skill-based and active physical activities as well as community-based activities. Mastery motivation and involvement in rehabilitation services enhanced involvement (intensity and diversity) in particular leisure activities, whereas cognitive and behavioral difficulties, activity limitations, and parental stress were obstacles to participation.