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Mijna Hadders-Algra

Publications and source records attributed to Mijna Hadders-Algra.

36 records · Page 2Linked to original sources

Postural muscle dyscoordination in children with cerebral palsy.

The present paper gives an overview of the knowledge currently available on muscular dyscoordination underlying postural problems in children with cerebral palsy (CP). Such information is a prerequisite for developing successful therapeutic interventions in children with CP. Until now, three children with CP functioning at GMFCS (Gross Motor Function Classification System) level V have been documented. The children totally or partially lacked direction specificity in their postural adjustments and could not sit independently for more than 3 seconds. Some children functioning at GMFCS level IV have intact direction-specific adjustments, whereas others have problems in generating consistently direction-specific adjustments. Children at GMFCS levels I to III have an intact basic level of control but have difficulties in fine-tuning the degree of postural muscle contraction to the task-specific conditions, a dysfunction more prominently present in children with bilateral spastic CP than in children with spastic hemiplegia. The problems in the adaptation of the degree of muscle contraction might be the reason that children with CP, more often than typically developing children, show an excess of antagonistic coactivation during difficult balancing tasks and a preference for cranial-caudal recruitment during during reaching. This might imply that both stereotypies might be regarded as functional strategies to compensate for the dysfunctional capacity to modulate subtly postural activity.

Adaptation, Physiological↗

Postural dysfunction in children with cerebral palsy: some implications for therapeutic guidance.

Postural problems play a central role in the motor dysfunction of children with cerebral palsy (CP). Therefore, they spend more time in sitting than in standing to perform vital tasks of daily life. The focus of this article is to describe the pathophysiology of postural control in sitting and outline some implications for management and treatment. In general, children with CP exhibit muscular activity counteracting forces that disturb equilibrium. Only 'non-sitting' children with severe CP lack such 'direction-specific' adjustments, possibly ruling out achievement of independent sitting. Most frequently, the children display dysfunctions in the adaptation of the adjustment. Typical characteristics of this adaptation in children with CP are a top-down recruitment of postural muscles, an excessive degree of antagonistic coactivation, and an incomplete adaptation of the EMG-amplitude to task specific constraints. Despite our knowledge on the pathophysiology underlying the postural problems in children with CP, little 'high-level' evidence (according to Sackett) exists on how different interventions can affect these problems. Therapeutic attention to promote motor performance in sitting focuses on adaptive seating, tilting of the support surface, and ample, variable training in motivating settings. The challenge facing us now is to provide evidence about the efficacy of specific treatment approaches facilitating that children reach an optimal level of functioning in daily life.

Cerebral Palsy↗

Development of postural control during the first 18 months of life.

The present paper reviews the development of postural adjustments during infancy. In the control of posture, two functional levels can be distinguished. The basic level deals with the generation of direction-specific adjustments, meaning that dorsal muscles are primarily activated when the body sways forward, whereas ventral muscles are primarily activated when the body sways backward. The second level is involved in adaptation of the direction-specific adjustments. Postural development starts with a repertoire of direction-specific adjustments suggesting that the basic level of control has an innate origin. At first, during the phase of primary variability, postural activity is largely variable and can be minimally adapted to environmental constraints. At 3 months, postural activity shows a transient period during which few postural muscles participate in postural activity. From 6 months onward, the phase of secondary variability starts, during which the second level of postural control becomes functionally active and infants develop the ability to adapt postural activity to the specifics of the situation. Initially, adaptation can be accomplished in a simple way only, but from 9-10 months onward, it can be performed by the subtle adaptation of the degree of muscle contraction. Around 13-14 months, anticipatory postural adjustments emerge. It is concluded that the development of postural adjustments is characterized by four periods of transition occurring at the ages of 3, 6, 9-10, and 13-14 months. The major transition occurs at 6 months, when infants move from the phase of non-adaptive, primary variability to the phase of adaptive, secondary variability.

Adaptation, Physiological↗

Kinematic characteristics of postural control during reaching in preterm children with cerebral palsy.

The relationships between kinematic characteristics of sitting posture during reaching movements of the dominant arm and 1) the kinematics of the reaching movement itself and 2) functional performance during daily life activities (PEDI) were assessed in 51 sitting preterm children with cerebral palsy (CP). The children were 2-11 y, 33 had spastic hemiplegia (SH) and 18 bilateral CP (Bi-CP). The data were compared with those of 26 typically developing children (TD). Sitting posture before the onset of reaching of children with CP differed from that of TD children: they sat with a more reclined pelvis and a more collapsed trunk. The more reclined pelvic position was associated with a better quality of reaching movements. The different sitting postures of pelvis and trunk were not related to functional performance during daily life activities. Displacement of the head, trunk, and pelvis of the children with CP did not differ from that of the TD children. Nevertheless, in the children with CP a more stable head, a more mobile trunk, and a more stable pelvis were related to better functional performance and/or a better quality of reaching. This suggests that physiotherapeutic guidance of children with CP should focus rather on the latter postural parameters than on the different sitting posture of pelvis and trunk.

Biomechanical Phenomena↗

Postural adjustments due to external perturbations during sitting in 1-month-old infants: evidence for the innate origin of direction specificity.

The aim of the study was to examine whether infants, at an age when they have no or little experience in sitting, can produce direction specific postural adjustments, i.e. synergies of muscle activity on the ventral side of the body during backward sway and on the dorsal side during forward sway. In addition, we addressed the question whether postural adjustments at this young age are restricted to single muscle responses or consist of a variable repertoire of muscle activation patterns including one during which all direction specific muscles participate ('complete' pattern). Postural adjustments due to external perturbations in a sitting position were studied in eight healthy infants aged 1 month. Multiple surface EMGs of neck, trunk and leg muscles and kinematics were recorded while the infants were exposed to horizontal forward (Fw) and backward (Bw) displacements of the surface of support. Direction specific postural adjustments, defined as adjustments during which agonist activation or antagonist inhibition preceded antagonist activation, were present in 85% of Bw and 72% of Fw translations. The direction specific adjustments showed a large variability with the repertoire of adjustments including the activation of one, two or all of the recorded direction specific muscles. The finding of direction specific adjustments at 1 month of age support the opinion that the basic level of organisation of postural adjustments has an innate origin. The finding of a variable repertoire of muscle response patterns, including the 'complete' pattern, refutes the idea that the development of postural adjustments results from gradual addition of appropriate muscles to the synergies.

Biomechanical Phenomena↗

General movements: A window for early identification of children at high risk for developmental disorders.

Detection of children with a developmental disorder, such as cerebral palsy, at an early age is notoriously difficult. Recently, a new form of neuromotor assessment of young infants was developed, based on the assessment of the quality of general movements (GMs). GMs are movements of the fetus and young infant in which all parts of the body participate. The technique of GM assessment is presented and the features of normal, mildly abnormal, and definitely abnormal GMs discussed. Essential to GM assessment is the Gestalt evaluation of movement complexity and variation. The quality of GMs at 2 to 4 months postterm (so-called fidgety GM age) has been found to have the highest predictive value. The presence of definitely abnormal GMs at this age--that is, GMs devoid of complexity and variation--puts a child at very high risk for cerebral palsy. This implies that definitely abnormal GMs at fidgety age are an indication for early physiotherapeutic intervention.

Age Factors↗

Postural control during reaching in preterm children with cerebral palsy.

Postural control during reaching with the dominant arm was assessed in 58 preterm children with cerebral palsy (CP) aged 2 to 11 years, comprising 34 with spastic hemiplegia (17 males, 17 females) and 24 with bilateral spastic CP (bilateral CP; 15 male, 9 females). Assessments were made by multiple surface electromyogram (EMG) and kinematic recording. Mean gestational age at birth for the children with spastic hemiplegia and those with bilateral CP was 28.6 weeks (SEM 0.33) and 28.2 weeks (SEM 0.34) respectively; their mean birthweights were 1158 g (SEM 58) and 1190 g (SEM 59) respectively. All but one of the children with spastic hemiplegia could walk without restriction, the exception being a child who had self-mobility with limitations. In the group of children with bilateral CP, nine walked without assistive devices, 10 could walk with assistive devices, and five children needed a wheelchair for self-mobility. Comparison data of 29 typically developing children (10 males, 19 females) born at term with appropriate birthweight were available. Results indicated that in most children with CP the basic level of postural control ('direction-specificity', i.e. muscle activation on the side opposite to direction of body sway) was intact. However, the children with CP showed dysfunctions in: (1) recruitment order of the postural muscles, i.e. they exhibited a stereotyped top-down recruitment; and (2) the ability to modulate muscle contraction (that registers on EMG) to task-specific conditions. The latter dysfunction was more pronounced in children with bilateral CP than in those with spastic hemiplegia. Postural dysfunctions were correlated to some extent with the degree of disability in everyday activities as assessed by the Pediatric Evaluation of Disability Inventory.

Age Factors↗

Quality of general movements and the development of minor neurological dysfunction at toddler and school age.

OBJECTIVE: To evaluate the reliability of assessing infants' general movements (GMs) using a new classification and its validity in predicting complex minor neurological dysfunction (MND) at toddler and at school age. DESIGN: Prospective study of two groups of infants, each consisting of a mix of low-risk and high-risk infants. SETTING: University Hospital Groningen, the Netherlands. SUBJECTS: Group A consisted of 16 low-risk and 21 high-risk infants; group B of 28 low-risk and 24 high-risk infants. MAIN OUTCOME MEASURES: Between term age and four months post term: multiple assessments of neurological condition by means of (a) assessment of GMs, and (b) a traditional neurological examination. GMs were classified into four classes using a standardized qualitative description: two classes of normal movements (normal-optimal and normal-suboptimal) and two classes of abnormal movements (mildly and definitely abnormal movements). Follow-up neurological examination with special attention to presence of MND was carried out in group A at 1 1/2 years, in group B at 4-9 years. RESULTS: GMs could be assessed reliably. They were stable over age in about 60% of the infants. Both the condition of the GMs and the infant neurological condition were significantly related to neurological condition at follow-up. Best prediction of complex MND was achieved when both types of infant assessment at the age of 2-4 months post term were combined. CONCLUSIONS: The assessment of GMs is a valuable tool, in particular when combined with the traditional neurological examination, to predict at early age the development of complex MND.

Child↗

Postural adjustments in preterm infants at 4 and 6 months post-term during voluntary reaching in supine position.

Gradually it is getting clear that motor development - in particular balance control - in so-called "low-risk" preterm infants often differs from that in full-term infants. However, little is known on the etiology and pathophysiology of these problems. The aim of this study was to evaluate postural behavior during reaching by means of kinetic and kinematic measurements. Preterm infants (n = 32) without cerebral palsy were investigated longitudinally at the corrected ages of 4 and 6 mo. Thirteen age-matched full-term infants served as controls. Cognitive and motor development were assessed by means of the quality of General Movements (GMs) at 4 mo and Bayley scales at 6 and 12 mo. The infants were lying supine on a forceplate reaching for a toy and the kinetics of the total body's Center of Pressure (COP) was measured in cranial-caudal and medial-lateral direction. The analysis focused on COP displacement, Vmax and oscillatory changes of the COP displacement during reaching. The kinematic analysis of reaching focused on movement units, Vmax and a compound kinematic variable reflecting the quality of reaching. The results showed that preterm infants showed a remarkable "still" postural behavior, which differed significantly from the mobile COP behavior of the full-term infants. More "still" postural behavior at 6 mo was associated with a better quality of reaching movements and with normal GMs at 4 mo. We concluded that "still" postural behavior is an adequate postural strategy of preterm infants. But it might be that this postural behavior is an indicator of later dysfunction.

Biomechanical Phenomena↗

Development of postural adjustments during reaching in sitting children.

We evaluated the development of postural adjustments accompanying reaching movements in sitting children. Twenty-nine typically developing children aged, 2-11 years, and ten adults were studied with multiple surface electromyograms (EMGs) and kinematics during reaching in four conditions: sitting with the seat-surface oriented horizontally with and without an additional task load, and sitting with the seat-surface tilted 15 degrees forward and 15 degrees backward. The development of postural adjustments during reaching in a sitting position turned out to have a non-linear and protracted course, which is not finished by the age of 11 years. The development of these adjustments is characterised by variation, yet specific developmental sequences could be distinguished. Firstly, the development of postural adjustments during reaching from the age of 2 years onwards lacked a preference for an en bloc strategy, which consists of an in concert activation of the direction-specific neck and trunk muscles. Secondly, anticipatory postural muscle activity, which was consistently present in adults, was virtually absent between 2 and 11 years of age. Thirdly, the data demonstrated that with increasing age the head gradually becomes the dominant frame of reference. In addition, the study suggested that, in terms of postural control, the forward-tilted position is the most efficient one.

Adult↗

Kinematic quality of reaching movements in preterm infants.

Many preterm infants may experience so-called minor developmental disorders; however, in general, the problems in motor behavior are not detected until school age. To introduce therapies aimed at the prevention of these problems, we need to increase our knowledge of motor function and dysfunction at early age. The present study focused on the organization of reaching movements in full-term and preterm infants without cerebral palsy. The reaching behavior of premature infants (n = 63) was assessed longitudinally at the corrected ages of 4 and 6 mo. Clinical assessments were made at 6 and 12 mo of age. On the basis of the infant's morbidity during the early stay in the neonatal intensive care unit, the preterm infants were allocated into a high-risk and a low-risk group. Results from a previous study in full-term infants (n = 13) were included. Kinematics of reaching movements in supine position were measured, and the analysis focused on movement velocity and movement units. A compound parameter of kinematic variables was created, reflecting the quality of reaching movements. The present study showed that at the age of 4 mo, low-risk preterm infants showed more often optimal reaching behavior than full-term and preterm high-risk infants. This better reaching performance was related to a better general motor and behavioral development during the first year of life. At the age of 6 mo, the advantage of the low-risk group in reaching behavior had disappeared and a disadvantage in the form of nonoptimal reaching behavior of the high-risk group emerged.

Arm↗

Deficient coordination of associated postural adjustments during a lifting task in children with neurodevelopmental disorders.

Precision grip and concomitant anticipatory postural adjustments were investigated in 11 children (three females, eight males; mean age 9 years 1 month, SD 11 months) with attention-deficit-hyperactivity disorder (ADHD); 12 children (three females, nine males; mean age 9 years, SD 7 months) with developmental coordination disorder (DCD), and 13 children (two females, 11 males; mean age 9 years 9 months, SD 11 months) with a combination of ADHD and DCD (ADHD+). There were two comparison groups: an age-matched group (four females, 11 males; mean age 9 years 1 month, SD 14 months) and a younger age group (five females, six males; mean age 6 years 5 months, SD 8 months). Adaptation to different weights was evaluated by lifting a specialized grip instrument monitoring grip force, load force, and centre of foot pressure displacements. Children with ADHD+ showed: (1) excessive grip forces, (2) decreased amplitude and prolonged onset of postural adjustments, and (3) reduced ability to adapt the motor output. Children with ADHD and DCD did not scale manual and postural forces in amplitude and time domains. Children with DCD also differed in delayed timing of postural adjustments. Results indicate that children with ADHD and DCD show a spectrum of neural dysfunctions underlying poor motor coordination, which are not specific to the clinical disorder.

Attention Deficit Disorder with Hyperactivity↗

Long-chain polyunsaturated fatty acids have a positive effect on the quality of general movements of healthy term infants.

BACKGROUND: Whether long-chain polyunsaturated fatty acids (LCPs) play a role in the development of the young nervous system in term infants is debated. OBJECTIVE: We investigated whether supplementation of formula with LCPs for 2 mo improves the quality of general movements (GMs) in healthy term infants at 3 mo of age. DESIGN: A prospective, double-blind, randomized controlled study was conducted with 2 groups of healthy term infants: a control-formula (CF) group (n = 131) and an LCP-supplemented-formula (LF) group (n = 119). A breastfed (BF) group (n = 147) served as a reference. Information on potential confounders was collected at enrollment. Videotapes were made of the infants' spontaneous motor behavior at 3 mo of age to assess the quality of their GMs. On the basis of quality, normal GMs were classified as normal-optimal or normal-suboptimal, and abnormal GMs were classified as mildly or definitely abnormal. Attrition at 3 mo of age was 15% and nonselective. Multivariate regression analyses with adjustment for confounders were carried out to evaluate the effect of the type of feeding. RESULTS: None of the infants had definitely abnormal GMs. Infants in the CF group had mildly abnormal GMs significantly more often than did infants in the LF and BF groups (31% compared with 19% and 20%, respectively). Infants in the BF group had normal-optimal GMs more frequently than did infants in the LF and CF groups (34% compared with 18% and 21%, respectively). Logistic regression analyses confirmed these findings. CONCLUSION: Supplementation of healthy term infants with LCPs during the first 2 mo of life reduces the occurrence of mildly abnormal GMs.

Breast Feeding↗

Developmental coordination disorder: is clumsy motor behavior caused by a lesion of the brain at early age?

Children presenting with Developmental Coordination Disorder or clumsiness often exhibit signs of minor neurological dysfunction (MND). The data of the Groningen Perinatal Project, a long-term follow-up project on the relations between prenatal and perinatal adversities and neurological, behavioral, and cognitive development revealed that two basic forms of MND can be distinguished: simple and complex MND. During school age children with simple MND are characterized by the presence of one or two dysfunctional clusters of MND, in adolescence by the presence of choreiform dyskinesia or hypotonia. Probably the major sources of origin of simple MND are genetic constitution and stress during early life. Simple MND might reflect the lower tail of the normal distribution of the quality of non-pathological brain function. In line with this hypothesis is the finding that simple MND is associatedwith only a moderately increased risk for learning- and behavioral problems. Children with complex MND present at school age with at least three dysfunctional clusters of MND, in adolescence with problems in fine manipulation or coordination. Perinatal adversities play an evident etiological role in the development of complex MND, suggesting that it might be attributed to a lesion of the brain at early age. In line with this idea is the finding that complex MND shows a strong correlation with attention and learning problems.

Adolescent↗

Trans isomeric octadecenoic acids are related inversely to arachidonic acid and DHA and positively related to mead acid in umbilical vessel wall lipids.

Long-chain PUFA play an important role in early human neurodevelopment. Significant inverse correlations were reported between values of trans isomeric and long-chain PUFA in plasma lipids of preterm infants and children aged 1-15 yr as well as in venous cord blood lipids of full-term infants. Here we report FA compositional data of cord blood vessel wall lipids in 308 healthy, full-term infants (gestational age: 39.7 +/- 1.2 wk, birth weight: 3528 +/- 429 g, mean +/- SD). The median (interquartile range) of the sum of 18-carbon trans FA was 0.22 (0.13) % w/w in umbilical artery and 0.16 (0.10) % w/w in umbilical vein lipids. Nonparametric correlation analysis showed significant inverse correlations between the sum of 18-carbon trans FA and both arachidonic acid and DHA in artery (r = -0.38, P < 0.01, and r = -0.20, P < 0.01) and vein (r = -0.36, P < 0.01, and -0.17, P < 0.01) wall lipids. In addition, the sum of 18-carbon trans FA was significantly positively correlated to Mead acid, a general indicator of EFA deficiency, in both artery (r = +0.35, P < 0.01) and vein (r = +0.31, P< 0.01) wall lipids. The present results obtained in a large group of full-term infants suggest that maternal trans FA intake is inversely associated with long-chain PUFA status of the infant at birth.

8,11,14-Eicosatrienoic Acid↗