Improvements in Muscle Strength Are Associated With Improvements in Walking Capacity in Young Children With Cerebral Palsy: A Secondary Analysis.

PURPOSE: To evaluate whether changes in lower-limb muscle strength explain changes in walking capacity during 14-week periods of usual care, power training and follow-up for children with spastic cerebral palsy. METHODS: Secondary analysis of a previously conducted double-baseline controlled trial of 22 children with spastic cerebral palsy. Generalized estimating equations were used to evaluate the relationships between within-subject changes in isometric muscle strength and walking capacity over 3 periods. RESULTS: Changes in hip abductor strength were associated with changes in the Muscle Power Sprint Test, changes in gastrocnemius and hip abductor strength were associated with changes in the Shuttle Run Test, and changes in gastrocnemius strength were associated with changes in the 1-minute walk test. All associations supported better walking capacity with increased strength. CONCLUSION: Walking capacity, especially sprint capacity, can be improved by increasing strength by functional power training in this population.

The Effect of Intrathecal Baclofen in Dyskinetic Cerebral Palsy: The IDYS Trial.

OBJECTIVE: Intrathecal baclofen treatment is used for the treatment of dystonia in patients with severe dyskinetic cerebral palsy; however, the current level of evidence for the effect is low. The primary aim of this study was to provide evidence for the effect of intrathecal baclofen treatment on individual goals in patients with severe dyskinetic cerebral palsy. METHODS: This multicenter, randomized, double-blind, placebo-controlled trial was performed at 2 university medical centers in the Netherlands. Patients with severe dyskinetic cerebral palsy (Gross Motor Functioning Classification System level IV-V) aged 4 to 24 years who were eligible for intrathecal baclofen were included. Patients were assigned by block randomization (2:2) for treatment with intrathecal baclofen or placebo for 3 months via an implanted microinfusion pump. The primary outcome was goal attainment scaling of individual treatment goals (GAS T score). A linear regression model was used for statistical analysis with study site as a covariate. Safety analyses were done for number and type of (serious) adverse events. RESULTS: Thirty-six patients were recruited from January 1, 2013, to March 31, 2018. Data for final analysis were available for 17 patients in the intrathecal baclofen group and 16 in the placebo group. Mean (standard deviation) GAS T score at 3 months was 38.9 (13.2) for intrathecal baclofen and 21.0 (4.6) for placebo (regression coefficient = 17.8, 95% confidence interval = 10.4-25.0, p < 0.001). Number and types of (serious) adverse events were similar between groups. INTERPRETATION: Intrathecal baclofen treatment is superior to placebo in achieving treatment goals in patients with severe dyskinetic cerebral palsy. ANN NEUROL 2019.

Use of the Dyskinesia Impairment Scale in non-ambulatory dyskinetic cerebral palsy.

AIM: To assess the responsiveness, concurrent validity, and feasibility of the Dyskinesia Impairment Scale (DIS) in non-ambulatory patients with dyskinetic cerebral palsy (CP). METHOD: The study is a secondary analysis of data collected in the IDYS trial, a randomized controlled trial on the effects of intrathecal baclofen (ITB). The DIS and Barry-Albright Dystonia Scale (BADS) were conducted at baseline and after 3 months of ITB or placebo treatment. Responsiveness was assessed by comparing the effect sizes and correlation of change after treatment between the DIS and BADS. Concurrent validity was evaluated by assessing the correlations between scales. Feasibility was evaluated for each DIS item by the number of participants who successfully accomplished the item. RESULTS: Thirty-three non-ambulatory patients (9 females, 24 males) with dyskinetic CP (ITB-treated: n=17, mean [SD] age: 14y 1mo [4y 1mo]; placebo-treated: n=16, mean [SD] age: 14y 7mo [4y]) were included in the study. The effect sizes for BADS and DIS were similar in The ITB-treated group (-0.29 and -0.22 respectively). Changes after treatment on the DIS dystonia subscale correlated with changes on the BADS (r=0.64; p<0.001). The DIS dystonia subscale and BADS correlated at baseline and follow-up (r=0.78; p<0.001 and r=0.79; p<0.001). Not all DIS activity items could be performed in this sample of patients. INTERPRETATION: For non-ambulatory patients with dyskinetic CP, the responsiveness of the DIS equalled the responsiveness of BADS. Concurrent validity was adequate. Feasibility for activity items was restricted in patients with severe dyskinetic CP. WHAT THIS PAPER ADDS: The Dyskinesia Impairment Scale (DIS) and Barry-Albright Dystonia Scale showed similar responsiveness in non-ambulatory patients with dyskinetic cerebral palsy (CP). No floor or ceiling effect was observed for DIS in non-ambulatory participants. The concurrent validity of DIS was adequate in non-ambulatory participants. Patients with dyskinetic CP in Gross Motor Function Classification System levels IV and V could not perform all DIS activity items.

Effect of continuous intrathecal baclofen therapy in children: a systematic review.

AIM: To investigate the effects of continuous intrathecal baclofen (ITB) therapy in children with cerebral palsy (CP) and other neurological conditions. METHOD: This systematic review was conducted using standardized methodology, searching four electronic databases (PubMed, Embase, CINAHL, Cochrane Library) for relevant literature published between inception and September 2017. Included studies involved continuous ITB as an intervention and outcome measures relating to all International Classification of Functioning, Disability and Health: Children and Youth (ICF-CY) components. RESULTS: Thirty-three studies were identified, of which one, including 17 children with spastic CP, produced level II evidence, and the others, mainly non-controlled cohort studies, level IV and V. Outcomes at body function level were most frequently reported. Results suggest continuous ITB may be effective in reducing spasticity and dystonia in CP, as well as other neurological conditions, and may improve the ease of care and quality of life of children with CP, but the level of evidence is low. INTERPRETATION: Despite three decades of applying ITB in children and a relatively large number of studies investigating the treatment effects, a direct link has not yet been demonstrated because of the low scientific quality of the primary studies. Further investigation into the effects of continuous ITB at all levels of the ICF-CY is warranted. Although large, controlled trials may be difficult to realize, national and international collaborations may provide opportunities. Also, multicentre prospective cohort studies with a long-term follow-up, employing harmonized outcome measures, can offer prospects to expand our knowledge of the effects of continuous ITB therapy in children. WHAT THIS PAPER ADDS: There is low-level evidence for continuous intrathecal baclofen (ITB) in children with cerebral palsy. Continuous ITB is effective in reducing spasticity and dystonia in non-controlled cohort studies. Evaluation of individual goals and systematic assessment of long-term effects in large cohort studies are required.

Intrathecal baclofen in metachromatic leukodystrophy.

Metachromatic leukodystrophy (MLD) is a rare progressive neurological disorder, often accompanied by motor impairments that are challenging to treat. In this case series, we report the course of treatment with intrathecal baclofen (ITB), aimed at improving daily care and comfort in children and young adults with MLD. All patients with MLD in our centre on ITB treatment for a minimum of 6 months were included (n=10; 4 males, 6 females; mean age 10y 8mo [range 6-24y]). Eight patients had MLD with a predominant spastic movement disorder (sMLD) and two were mainly dyskinetic. Patients with sMLD were compared with matched patients with spastic cerebral palsy (CP). Complication rates related to ITB treatment were similar in both groups. ITB treatment course in the first 6 months after pump implantation appears to show more dose increase in most patients MLD, compared to patients with spastic CP. This may be due to the progressive disease in MLD. ITB is a feasible therapy to improve daily care and comfort in patients with MLD and should therefore be considered early. WHAT THIS PAPER ADDS: Intrathecal baclofen (ITB) is a feasible therapy to improve comfort and daily care in children and young people with metachromatic leukodystrophy (MLD). In the first 6 months of ITB treatment, MLD seems to show more dose increase compared to spastic cerebral palsy.

Risk Factors for Dystonia after Selective Dorsal Rhizotomy in Nonwalking Children and Adolescents with Bilateral Spasticity.

We recently showed a beneficial effect of selective dorsal rhizotomy (SDR) on daily care and comfort in nonwalking children with severe bilateral spasticity. However, despite careful selection, some patients showed dystonia after the intervention, in which cases caregivers tended to be less satisfied with the result.The aim of this study is to identify risk factors for dystonia after SDR in children and adolescents with severe bilateral spasticity (GMFCS levels IV/V).Clinical and MRI risk factors for dystonia after SDR were studied in our cohort of 24 patients. Patients with clinical evidence of dystonia and brain MRI showing basal ganglia abnormalities were excluded for SDR.Nine of 24 patients (38%) showed some degree of dystonia after SDR. There was a significant association between the cause of spasticity and dystonia after SDR; in six (67%) patients with a congenital disorder, dystonia was present versus three (20%) with an acquired disorder (Chi-squared test: C(1) = 5.23, p = 0.02).This study allows more optimal selection of patients that may benefit from SDR. Patients with an acquired cause of spasticity, when selected carefully on clinical examination and MRI, rarely show dystonia after SDR. However, patients with an underlying congenital disorder have a considerable risk of dystonia after SDR.

Effectiveness of Functional Power Training on Walking Ability in Young Children With Cerebral Palsy: Study Protocol of a Double-Baseline Trial.

PURPOSE: To evaluate the effect of functional high-velocity resistance (power) training to improve walking ability of young children with cerebral palsy. METHODS: Twenty-two children with bi- or unilateral spastic cerebral palsy, Gross Motor Function Classification System levels I and II, aged 4 to 10 years will be recruited. A double-baseline design will be used to compare a 14-week functional power training (3 times a week) program with a 14-week usual care period and a 14-week follow-up period. The power exercises will be loaded and performed at 50% to 70% of the maximum unloaded speed. Load will be increased when exercises are performed faster than 70% of the unloaded speed. Primary outcomes will be sprinting capacity (15-m Muscle Power Sprint Test) and goal attainment scaling score of walking-related treatment goals. Secondary outcomes will be walking speed (1-min walk test), endurance (10-m shuttle run test), gross motor function, lower-limb strength, and parent-reported mobility.

Freehand three-dimensional ultrasound to assess semitendinosus muscle morphology.

In several neurological disorders and muscle injuries, morphological changes of the m. semitendinosus (ST) are presumed to contribute to movement limitations around the knee. Freehand three-dimensional (3D) ultrasound (US), using position tracking of two-dimensional US images to reconstruct a 3D voxel array, can be used to assess muscle morphology in vivo. The aims of this study were: (i) to introduce a newly developed 3D US protocol for ST; and (ii) provide a first comparison of morphological characteristics determined by 3D US with those measured on dissected cadaveric muscles. Morphological characteristics of ST (e.g. muscle belly length, tendon length, fascicle length and whole muscle volume, and volumes of both compartments) were assessed in six cadavers using a 3D US protocol. Subsequently, ST muscles were removed from the body to measure the same morphological characteristics. Mean differences between morphological characteristics measured by 3D US and after dissection were smaller than 10%. Intra-class correlation coefficients (ICCs) were higher than 0.75 for all variables except for the lengths of proximal fascicles (ICC = 0.58). Measurement of the volume of proximal compartment by 3D US was not feasible, due to low US image quality proximally. We conclude that the presented 3D US protocol allows for reasonably accurate measurements of key morphological characteristics of ST muscle.

Botulinum neurotoxin treatment in children with cerebral palsy: validation of a needle placement protocol using passive muscle stretching and relaxing.

AIM: To validate a detailed intramuscular needle placement protocol using passive muscle stretching and relaxing for botulinum neurotoxin type A (BoNT-A) treatment in the lower extremity of children with spastic cerebral palsy (CP), with verification by electrical stimulation. METHOD: A prospective observational study was performed in 75 children with spastic CP who received regular BoNT-A treatment under general anaesthesia (52 males, 23 females; mean age 8y 9mo, SD 3y 7mo, range 4-18y; mean body mass index 16.2, SD 3.7, range 7.7-26.7). A total of 1084 intramuscular needle placements using passive muscle stretching and relaxing were verified by electrical stimulation. Primary outcome was the positive predictive value. RESULTS: Intramuscular needle placement in the muscles adductor brevis, adductor longus, gracilis, semimembranosus, semitendinosus, biceps femoris, rectus femoris, and lateral and medial heads of the gastrocnemius and soleus had a positive predictive value ranging from 85.7% to 100% (95% confidence interval ranging from 71.5-89.9% to 91.4-100%). INTERPRETATION: This validated detailed protocol for intramuscular needle placement using passive muscle stretching and relaxing for BoNT-A treatment in the lower extremity of children with spastic CP is reliable and has a high positive predictive value.

Longitudinal Association Between Gross Motor Capacity and Neuromusculoskeletal Function in Children and Youth With Cerebral Palsy.

OBJECTIVE: To examine associations over longitudinal measurements between neuromusculoskeletal function and gross motor capacity in children and youth with cerebral palsy (CP). DESIGN: A prospective cohort study. SETTING: Rehabilitation departments of university medical centers and rehabilitations centers. PARTICIPANTS: A sample (N=327) consisting of 148 children (aged 5-9y) and 179 youth (aged 11-20y) with CP, Gross Motor Function Classification System level I (n=180), level II (n=44), level III (n=36), level IV (n=34), and level V (n=33). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Gross motor capacity was assessed with the Gross Motor Function Measure-66 over a period of 2 to 4 years in different age cohorts. Neuromusculoskeletal function included selective motor control (SMC), muscle strength, spasticity, and range of motion (ROM) of the lower extremities. RESULTS: Multilevel analyses showed that SMC was significantly associated with gross motor capacity in children and youth with CP, showing higher values and a more favorable course of gross motor capacity in those with better SMC. Strength was only associated with gross motor capacity in youth. Reduced ROM of hip (children) and knee extension (youth) and spasticity of the hip adductors (youth) were additionally-but more weakly-associated with lower values and a less favorable course of gross motor capacity. CONCLUSIONS: Results indicate that children and youth with more severely impaired SMC and youth with reduced muscle strength have a less favorable course of gross motor capacity, while spasticity and reduced ROM are less determinative.

Medial gastrocnemius muscle growth during adolescence is mediated by increased fascicle diameter rather than by longitudinal fascicle growth.

Using a cross-sectional design, the purpose of this study was to determine how pennate gastrocnemius medialis (GM) muscle geometry changes as a function of adolescent age. Sixteen healthy adolescent males (aged 10-19 years) participated in this study. GM muscle geometry was measured within the mid-longitudinal plane obtained from a 3D voxel-array composed of transverse ultrasound images. Images were taken at footplate angles corresponding to standardised externally applied footplate moments (between 4 Nm plantar flexion and 6 Nm dorsal flexion). Muscle activity was recorded using surface electromyography (EMG), expressed as a percentage of maximal voluntary contraction (%MVC). To minimise the effects of muscle excitation, EMG inclusion criteria were set at <10% of MVC. In practice, however, normalised EMG levels were much lower. For adolescent subjects with increasing ages, GM muscle (belly) length increased due to an increase in the length component of the physiological cross-sectional area measured within the mid-longitudinal plane. No difference was found between fascicles at different ages, but the aponeurosis length and pennation angle increased by 0.5 cm year(-1) and 0.5° per year, respectively. Footplate angles corresponding to externally applied 0 and 4 Nm plantarflexion moments were not associated with different adolescent ages. In contrast, footplate angles corresponding to externally applied 4 and 6 Nm dorsal flexion moments decreased by 10° between 10 and 19 years. In conclusion, we found that in adolescents' pennate GM muscles, longitudinal muscle growth is mediated predominantly by increased muscle fascicle diameter.

Associations between fitness and mobility capacity in school-aged children with cerebral palsy: a longitudinal analysis.

AIM: The aim of this study was to determine the longitudinal associations among fitness components and between fitness and mobility capacity in children with cerebral palsy (CP). METHOD: Forty-six children (26 males, 20 females; mean age 9y 7mo [SD 1y 8mo]) with a bilateral (n=24) or a unilateral spastic CP (n=22) participated in aerobic and anaerobic fitness measurements on a cycle ergometer and isometric muscle strength tests (Gross Motor Function Classification System [GMFCS] level I [n=26], level II [n=12], level III [n=8]). Mobility capacity was assessed with the gross motor function measure (GMFM) and a walking capacity test. Associations over longitudinal measurements (three or four measurements over 1y) were determined since longitudinal data allow a more accurate estimation. The associations were determined using a mixed model with fixed effects (mobility capacity as dependent variables and fitness components as independent variables) and a random intercept. RESULTS: In children with bilateral CP, changes in aerobic fitness were associated with changes in anaerobic fitness (p<0.001), and changes in aerobic fitness showed an association with changes in muscle strength (p<0.05). Anaerobic fitness was not associated with muscle strength. No associations between fitness components were found in unilateral CP. Anaerobic fitness and muscle strength were significant determinants for GMFM and walking capacity in bilateral but not in unilateral CP. INTERPRETATION: The longitudinal associations between aerobic and anaerobic fitness and mobility indicate that increasing either aerobic or anaerobic fitness is associated with improvements in mobility in children with bilateral CP. While increasing anaerobic fitness might be beneficial for mobility capacity in children with bilateral CP, this is less likely for children with unilateral CP.

Comprehension of spoken language in non-speaking children with severe cerebral palsy: an explorative study on associations with motor type and disabilities.

AIM: To assess spoken language comprehension in non-speaking children with severe cerebral palsy (CP) and to explore possible associations with motor type and disability. METHOD: Eighty-seven non-speaking children (44 males, 43 females, mean age 6y 8mo, SD 2y 1mo) with spastic (54%) or dyskinetic (46%) CP (Gross Motor Function Classification System [GMFCS] levels IV [39%] and V [61%]) underwent spoken language comprehension assessment with the computer-based instrument for low motor language testing (C-BiLLT), a new and validated diagnostic instrument. A multiple linear regression model was used to investigate which variables explained the variation in C-BiLLT scores. Associations between spoken language comprehension abilities (expressed in z-score or age-equivalent score) and motor type of CP, GMFCS and Manual Ability Classification System (MACS) levels, gestational age, and epilepsy were analysed with Fisher's exact test. A p-value <0.05 was considered statistically significant. RESULTS: Chronological age, motor type, and GMFCS classification explained 33% (R=0.577, R(2) =0.33) of the variance in spoken language comprehension. Of the children aged younger than 6 years 6 months, 52.4% of the children with dyskinetic CP attained comprehension scores within the average range (z-score ≥-1.6) as opposed to none of the children with spastic CP. Of the children aged older than 6 years 6 months, 32% of the children with dyskinetic CP reached the highest achievable age-equivalent score compared to 4% of the children with spastic CP. No significant difference in disability was found between CP-related variables (MACS levels, gestational age, epilepsy), with the exception of GMFCS which showed a significant difference in children aged younger than 6 years 6 months (p=0.043). INTERPRETATION: Despite communication disabilities in children with severe CP, particularly in dyskinetic CP, spoken language comprehension may show no or only moderate delay. These findings emphasize the importance of introducing alternative and/or augmentative communication devices from early childhood.

Assessment of net knee moment-angle characteristics by instrumented hand-held dynamometry in children with spastic cerebral palsy and typically developing children.

BACKGROUND: The limited range of motion during walking in children with spastic cerebral palsy (SCP) may be the result of altered mechanical characteristics of muscles and connective tissues around the knee joint. Measurement of static net knee moment-angle relation will provide insights into these alterations, for which instrumented hand-held dynamometry may be applied. The aims of this study were: (1) to test the measurement error of the estimated net knee moment-angle characteristics, (2) to determine the correlation between knee extension angle measurement at a standardized knee moment and popliteal angle from common physical examination and (3) to compare net knee moment-angle characteristics in SCP versus typically developing children. METHODS: With the child lying in sideward position, the knee was extended by moving the lower leg by a hand-held force transducer on a low friction cart. Force data were collected for a range of knee angles. Data were excluded when activity (EMG) levels of knee extensor and flexor muscles exceeded the EMG level during rest by more than two standard deviations. The net knee flexion moments were calculated from recorded force data and measured moment arm. Reliability for knee angles corresponding with 0.5, 1, 2, 3, and 4 Nm knee net flexion moments was assessed by standard error of measurements (SEM) and smallest detectable difference (SDD). RESULTS: For between day comparison, SEMs were about 5° and SDDs were below 14° for knee angles at 1-4 Nm net knee flexion moments. In SCP children, the knee angle measured at 4 Nm knee flexion moment was not related to the popliteal angle (r = 0.52). The slope at 4 Nm of the knee moment-angle curve in SCP children was significantly higher than that in typically developing children. CONCLUSIONS: The presented knee hand-held dynamometry allows assessment of net knee flexion moment-knee angle characteristics in typically developing and SCP children and can be used to identify clinically relevant changes as a result of treatment. Overall stiffness of structures that contribute to the net knee flexion moment at the knee (i.e. muscles, tendons, ligaments) is elevated in SCP children.

Selection criteria for selective dorsal rhizotomy in children with spastic cerebral palsy: a systematic review of the literature.

AIM: Information regarding the selection procedure for selective dorsal rhizotomy (SDR) in children with spastic cerebral palsy (CP) is scarce. Therefore, the aim of this study was to summarize the selection criteria for SDR in children with spastic CP. METHOD: A systematic review was carried out using the following databases: MEDLINE, CINAHL, EMBASE, PEDro, and the Cochrane Library. Additional studies were identified in the reference lists. Search terms included 'selective dorsal rhizotomy', 'functional posterior rhizotomy', 'selective posterior rhizotomy', and 'cerebral palsy'. Studies were selected if they studied mainly children (<18y of age) with spastic CP, if they had an intervention of SDR, if they had a detailed description of the selection criteria, and if they were in English. The levels of evidence, conduct of studies, and selection criteria for SDR were scored. RESULTS: Fifty-two studies were included. Selection criteria were reported in 16 International Classification of Functioning, Disability and Health model domains including 'body structure and function' (details concerning spasticity [94%], other movement abnormalities [62%], and strength [54%]), 'activity' (gross motor function [27%]), and 'personal and environmental factors' (age [44%], diagnosis [50%], motivation [31%], previous surgery [21%], and follow-up therapy [31%]). Most selection criteria were not based on standardized measurements. INTERPRETATION: Selection criteria for SDR vary considerably. Future studies should describe clearly the selection procedure. International meetings of experts should develop more uniform consensus guidelines, which could form the basis for selecting candidates for SDR.

Developmental trajectories of receptive and expressive communication in children and young adults with cerebral palsy.

AIM: The aim of this study was to determine the developmental trajectories of expressive (speech) and receptive (spoken and written language) communication by type of motor disorder and intellectual disability in individuals with cerebral palsy (CP). METHOD: The development of 418 participants (261 males, 157 females; mean age 9y 6mo [SD 6y 2mo], range 1-24y; Gross Motor Function Classification System (GMFCS) level I [n=206], II [n=57], III [n=59], IV [n=54], V [n=42]) was followed for 2 to 4 years in a longitudinal study. Communication performance was measured using the Vineland Adaptive Behavior Scales. The type of motor disorder was differentiated by type of CP as unilateral spastic (USCP, n=161), bilateral spastic (BSCP, n=202), and non-spastic (NSCP, n=55), while intellectual disability was determined by IQ or school type (regular or special). A multilevel analysis was then used to model the developmental trajectories. RESULTS: The most favourable development of expressive communication was seen in USCP (vs BSCP ß [SE]-2.74 [1.06], NSCP ß [SE]-2.67 [1.44]). The difference between the development trajectory levels of children with and without intellectual disability was smaller for children with USCP than for those with BSCP and NSCP. For receptive communication, the most favourable development was found for all children with USCP and for BSCP or NSCP without intellectual disability (vs intellectual disability ß [SE]-4.00 [1.16]). Development of written language was most favourable for children without intellectual disability (vs intellectual disability ß [SE]-23.11 [2.85]). INTERPRETATION: The development of expressive communication was found to be most closely related to type of motor disorder, whereas the development of receptive communication was found to be most closely related to intellectual disability.

Assessment of muscle endurance of the knee extensor muscles in adolescents with spastic cerebral palsy using a submaximal repetitions-to-fatigue protocol.

OBJECTIVE: To compare muscle endurance in adolescents with spastic cerebral palsy (CP) with typically developing (TD) peers using a submaximal repetitions-to-fatigue (RTF) protocol. DESIGN: Cross sectional. SETTING: Human motion laboratory. PARTICIPANTS: Adolescents with spastic CP (n=16; Gross Motor Function Classification System levels I or II) and TD adolescents (n=18) within the age range of 12 to 19 years old. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Each participant performed 3 RTF tests at different submaximal loads, ranging from 50% to 90% of their maximal voluntary knee extension torque. The relation between the number of repetitions (repetition maximum [RM]) and imposed submaximal relative (percent of maximal voluntary torque [%MVT]) and absolute (Nm/kg) torque was quantified. To compare adolescents with CP with TD adolescents, a mixed linear model was used to construct load endurance curves. Surface electromyography of quadriceps muscles was measured to assess changes in normalized amplitude and median frequency (MF) as physiological indicators of muscle fatigue. RESULTS: Adolescents with CP showed a larger decrease in %MVT per RM than TD adolescents (P<.05). TD adolescents showed substantial higher absolute (Nm/kg) load endurance curves than adolescents with CP (P<.001), but they did not show a difference in slope. Electromyographic normalized amplitude increased significantly (P<.05) in the quadriceps muscles in all tests for both groups. Electromyographic MF decreased significantly (P<.05) in tests with the low and medium loads. Electromyographic responses did not differ between groups, indicating that similar levels of muscle fatigue were reached. CONCLUSIONS: Adolescents with CP show slightly lower muscle endurance compared with TD adolescents on a submaximal RTF protocol, which is in contrast with earlier findings in a maximal voluntary fatigue protocol. Accordingly, adolescents with CP have a reduced capacity to endure activities at similar relative loads compared with TD adolescents.

The effectiveness of a physical activity stimulation programme for children with cerebral palsy on social participation, self-perception and quality of life: a randomized controlled trial.

OBJECTIVE: To determine the effects of a six-month physical activity stimulation programme on social participation, self-perception and quality of life in children with cerebral palsy. DESIGN: Multicentre randomized controlled trial with concealed allocation, blinded assessments and intention-to-treat analysis. SETTING: Paediatric physiotherapy practices, special schools for children with a disability, and the child's own home. SUBJECTS: Forty-nine children with spastic cerebral palsy (28 male), aged 7-13 years, able to walk with and without walking aids. INTERVENTIONS: The intervention group followed a six-month physical activity stimulation programme involving counselling through motivational interviewing, home-based physiotherapy and four months of fitness training. The control group continued regular paediatric physiotherapy. MAIN MEASURES: Outcomes included social participation in domestic life, social participation in recreation and leisure (Life-Habits for Children questionnaire and Children's Assessment of Participation and Enjoyment questionnaire), self-perception (Harter's Self-Perception Profile for Children) and parent-reported quality of life (Cerebral Palsy Quality of Life Questionnaire). Assessments were performed at baseline, at six months (except quality of life) and at twelve months. RESULTS: Intervention resulted in a positive effect on social participation in domestic life at twelve months (mean between-group difference = 0.9, 95% confidence interval (CI) = 0.1 to 1.7 [1-10 scale], P = 0.03), but not at six months. No significant effects were found for social participation in recreation and leisure, self-perception at six months and twelve months or for quality of life at twelve months. CONCLUSIONS: The combination of counselling, home-based physiotherapy and fitness training was not effective in improving social participation in recreation and leisure, self-perception or quality of life, but did show a potential for improving social participation in domestic life over the longer term.

Defining the mechanical properties of a spring-hinged ankle foot orthosis to assess its potential use in children with spastic cerebral palsy.

A rigid ventral shelf ankle foot orthosis (AFO) may improve gait in children with spastic cerebral palsy (SCP) whose gait is characterized by excessive knee flexion in stance. However, these AFOs can also impede ankle range of motion (ROM) and thereby inhibit push-off power. A more spring-like AFO can enhance push-off and may potentially reduce walking energy cost. The recent development of an adjustable spring-hinged AFO now allows adjustment of AFO stiffness, enabling tuning toward optimal gait performance. This study aims to quantify the mechanical properties of this spring-hinged AFO for each of its springs and settings. Using an AFO stiffness tester, two AFO hinges and their accompanying springs were measured. The springs showed a stiffness range of 0.01-1.82 N · m · deg(-1). The moment-threshold increased with increasing stiffness (1.13-12.1 N · m), while ROM decreased (4.91-16.5°). Energy was returned by all springs (11.5-116.3 J). These results suggest that the two stiffest available springs should improve joint kinematics and enhance push-off in children with SCP walking with excessive knee flexion.