Typical general movements at 2 to 4 months:Movement complexity, fidgety movements, and their associations with risk factors and SINDA scores

Background: Movement complexity and the presence of fidgety movements (FMs) during general movements (GMs) both reflect aspects of neurological integrity in early infancy. Aim: To assess interrelations between the degree of movement complexity and characteristics of FMs during typical GMs and to investigate associations between mildly impaired GMs and risk factors and neurodevelopmental condition. Study design: Observational cohort study. Subjects: 283 infants (25 born preterm) at 2-4 months corrected age, representative of the general Dutch population. Outcome measures: GMs were classified in terms of GM-complexity (normal or mildly abnormal (MA)) and FMs (clearly present, sporadic, or exaggerated). Concurrent neurological, developmental and socio-emotional status were measured with the Standardized Infant NeuroDevelopmental Assessment (SINDA). Results: Infants with MA GM-complexity had a higher risk of having sporadic FMs and exaggerated FMs. Perinatal complications were not associated with mildly impaired GMs. MA GM-complexity was associated with advanced maternal age (adjusted OR = 2.29 [1.11, 4.76]) and having a non-native Dutch mother (adjusted OR = 2.93 [1.29, 6.64]). It was also associated with atypical neurological (OR = 7.62 [3.51, 16.54]) and developmental scores (OR = 2.38 [1.16, 4.88]). Sporadic and exaggerated FMs were associated with low-to-middle maternal education (adjusted OR = 2.88, [1.45, 5.72]) and having a non-native Dutch father (adjusted OR = 7.16 [1.41, 36.32]), respectively. However, neither sporadic nor exaggerated FMs were associated with the SINDA outcomes. Conclusions: GM-complexity and FMs are two interrelated but different aspects of GMs. Mild impairments in GM-complexity and FMs share a non-optimal socio-economic background as risk factor, but only MA GM-complexity is associated with a concurrent non-optimal neurodevelopmental condition

Atypical knee jerk responses in high-risk children:A longitudinal EMG-study

INTRODUCTION: We previously found that atypical responses to the knee jerk reflex, i.e., tonic responses (TRs), clonus and contralateral responses in very high-risk (VHR) infants were associated with cerebral palsy (CP) at 21 months. The current study aimed for a better understanding of pathophysiology of atypical knee jerk responses by evaluating whether infant atypical knee jerk responses are associated with CP and atypical knee jerk responses at school-age. METHODS: 31 VHR-children, who had also been assessed longitudinally during infancy, and 24 typically developing children, were assessed at 7-10 years (school-age). We continuously recorded surface EMG of thigh muscles during knee jerk responses longitudinally during infancy and once at school-age. Neurological condition was assessed with age-appropriate neurological examinations. It included the diagnosis of CP at 21 months corrected age and school-age. CP's type and severity (Gross Motor Function Classification System (GMFCS)) were reported. RESULTS: Persistent TRs in infancy were associated with CP at school-age. TR prevalence decreased from infancy to childhood. At school-age it was no longer associated with CP. Clonus prevalence in VHR-children did not change with increasing age; it was significantly higher in children without than those with CP. Reflex irradiation was common in all school-age children, and its prevalence in contralateral muscles in VHR-children decreased between infancy and childhood. CONCLUSIONS: In infancy, TRs indicated an increased risk of CP, but at school-age TRs were not associated with CP. In general, spinal hyperexcitability, expressed as reflex irradiation and TRs, decreased between infancy and school-age

Longer duration of gestation in term singletons is associated with better infant neurodevelopment

Background: Longer gestation at term and post-term age is associated with increased perinatal mortality. Nonetheless, recent neuroimaging studies indicated that longer gestation is also associated with better functioning of the child's brain. Aims: to assess whether longer gestation in term and post-term (in short: term) singletons is associated with better infant neurodevelopment. Study design: cross-sectional observational study. Subjects: Participants were all singleton term infants (n = 1563) aged 2–18 months of the IMP-SINDA project that collected normative data for the Infant Motor Profile (IMP) and Standardized Infant NeuroDevelopmental Assessment (SINDA). The group was representative of the Dutch population. Outcome measures: Total IMP score was the primary outcome. Secondary outcomes were atypical total IMP scores (scores &lt;15th percentile) and SINDA's neurological and developmental scores. Results: Duration of gestation had a quadratic relationship with IMP and SINDA developmental scores. IMP scores were lowest at a gestation of 38·5 weeks, SINDA developmental scores at 38·7 weeks. Next, both scores increased with increasing duration of gestation. Infants born at 41–42 weeks had significantly less often atypical IMP scores (adjusted OR [95 % CI]: 0·571 [0·341–0·957] and atypical SINDA developmental scores (adjusted OR: 0·366 [0·195–0·688]) than infants born at 39–40 weeks. Duration of gestation was not associated with SINDA's neurological score. Conclusions: In term singleton infants representative of the Dutch population longer gestation is associated with better infant neurodevelopment scores suggesting better neural network efficiency. Longer gestation in term infants is not associated with atypical neurological scores.</p

Infant motor behaviour and functional and cognitive outcome at school-age:A follow-up study in very high-risk children

BACKGROUND: The Infant Motor Profile (IMP) is an appropriate tool to assess and monitor infant motor behaviour over time. Infants at very high risk (VHR) due to a lesion of the brain generally show impaired motor development. They may grow into or out of their neurodevelopmental deficit. AIMS: Evaluate associations between IMP-trajectories, summarised by IMP-scores in early infancy and rates of change, and functional and cognitive outcome at school-age in VHR-children. STUDY DESIGN: Longitudinal study. SUBJECTS: 31 VHR-children, mainly due to a brain lesion, who had multiple IMP-assessments during infancy, were re-assessed at 7-10 years (school-age). OUTCOME MEASURES: Functional outcome was assessed with the Vineland-II, cognition with RAKIT 2. Associations between IMP-trajectories and outcome were tested by multivariable linear regression analyses. RESULTS: When corrected for sex, maternal education and follow-up age, initial scores of total IMP, variation and performance domains, as well as their rates of change were associated with better functional outcome (unstandardised coefficients [95% CI]): 36.44 [19.60-53.28], 33.46 [17.43-49.49], 16.52 [7.58-25.46], and 513.15 [262.51-763.79], 356.70 [148.24-565.15], and 269 [130.57-407.43], respectively. Positive rates of change in variation scores were associated with better cognition at school-age: 34.81 [16.58-53.03]. CONCLUSION: Our study indicated that in VHR-children IMP-trajectories were associated with functional outcome at school-age, and to a minor extent also with cognition. Initial IMP-scores presumably reflect the effect of an early brain lesion on brain functioning, whereas IMP rate of change reflects whether infants are able to grow into or out of their initial neurodevelopmental deficit

Motor behaviour in infancy is associated with neurological, cognitive, and behavioural function of children born to parents with reduced fertility

AIM: To evaluate the associations between motor development in infancy and developmental outcomes at school age. METHOD: Participants were 195 children (99 males, 96 females; mean age [SD] 9y 3mo [3mo], range 8y 4mo-10y 11mo) born to couples whose reduced fertility was or was not treated with assisted reproductive technologies. Motor behaviour was assessed at 4, 10, and 18 months with the Infant Motor Profile (IMP). IQ, neurological optimality score (NOS), and behavioural problem scores were measured at 9 years with the Wechsler Abbreviated Scale of Intelligence, minor neurological dysfunction assessment, and the Child Behavior Checklist respectively. RESULTS: Children with a slow developmental trajectory in the IMP-domain adaptability had an IQ 12.6 points lower (95% confidence interval [CI] 4.7-20.4) and an NOS 3.4 points lower (95% CI 0.7-6.2) at 9 years of age than children with typical adaptability development. Children with a slow developmental trajectory in the IMP-domain performance had an IQ 5.0 points lower (95% CI 0.7-9.3) than children with typical performance development. A non-optimal trajectory in IMP-variation and a fluctuating trajectory in IMP-fluency were associated with higher internalizing scores of 3.6 and 5.8 points respectively, than infants with optimal IMP-domain trajectories. INTERPRETATION: In relatively low-risk children, motor behaviour in infancy was associated with neurological, cognitive, and behavioural function at school age

Development of muscle tone impairments in high-risk infants:Associations with cerebral palsy and cystic periventricular leukomalacia

AIM: To assess the prevalence and development of muscle tone impairments in infants at high risk of developmental disorders, and their associations with cerebral palsy (CP) and cystic periventricular leukomalacia (cPVL). METHOD: Longitudinal exploration of muscle tone in 39 infants at high risk of CP (LEARN2MOVE 0-2 project) mostly due to an early lesion of the brain. Muscle tone was assessed ≥4 times between 0 and 21 months corrected age (CA) with the Touwen Infant Neurological Examination. Diagnosis of CP was determined at 21 months CA. Neonatal neuro-imaging was available. Developmental trajectories were calculated using generalized linear mixed effect models. RESULTS: Infants showed atypical muscle tone in three or four body parts in 93% (172/185) of the assessments. The most prevalent muscle tone pattern was hypotonia of neck and trunk with hypertonia of the limbs (28%). From 7 months CA onwards hypertonia of the arms was associated with CP. Asymmetric arm tone during infancy was associated with unilateral CP. At 18-21 months CA ankle hypertonia was associated with CP at 21 months; leg hypertonia in infancy was not associated with CP. Leg hypertonia was associated with cPVL, regardless of age. INTERPRETATION: High-risk infants due to an early lesion of the brain often present with muscle tone impairment. In these infants, hypertonia and asymmetric muscle tone of the arms were from 7 months onwards associated with the diagnosis of CP at 21 months; hypertonia of the legs was not

Evaluation of neuromotor function in infancy - A systematic review of available methods

Objective: Neuromotor function in infancy can be evaluated in various ways. Assessment instruments are used for early detection of children with a high risk for developmental disorders. Early detection enables clinicians to provide intervention at a young age when plasticity of the nervous system is high. The assessments may also be used to monitor intervention. The present article will review the psychometric properties of methods to assess neuromotor function in infancy. Method: A literature search was performed in PubMed, Medline, and PsycINFO (1966-2007) on instruments to assess neuromotor functioning of infants. Results: Fifteen instruments were included and classified into 4 groups: (1) Comprehensive neurological examinations (n = 4). These techniques are widely used, though little is known about their reliability. Their validity in predicting major developmental disorders such as cerebral palsy is good; their predictive validity for minor motor disorders is moderate at best. (2) Procedures with standardized scoring (n = 7). These have good reliability, but only moderate predictive validity for major developmental disorders. No data available for prediction of minor developmental disorders. (3) Observation of milestones (n = 2). Its predictive validity for major developmental disorders is only moderate, whereas reliability is good. (4) Assessment of quality of motor behavior or motor patterns (n = 2). These instruments have the best predictive validity for major and minor developmental motor disorders, but current methods are only useful under the age of 4 months. Conclusion: Prediction of developmental outcome at an early age is difficult. In medical evaluations of high-risk infants, the best predictions are achieved through a combination of multiple, complementary tools, that is, achieved milestones, neurological examination and assessment of the quality of motor behavior

The Infant Motor Profile

The Infant Motor Profile is a practical manual on a new, evidence-based method to assess infant motor behaviour. Not only looking at what milestones the infant has reached, but also paying attention to the quality of motor behaviour – how the infant moves – this text provides professionals involved in the care of infants at risk of developmental disorders with information on five domains of motor behaviour: variation, adaptability, symmetry, fluency, and performance. Backed up by extensive, up-to-date research, it includes percentile curves so that professionals can easily interpret the infants’ scores. The profile created from the assessment informs about the infant’s current condition and their risk of developmental disorders, as well as providing suggestions for early intervention, tailored to the strengths and limitations of the infant. Used over time, it can be an excellent instrument to monitor the infant’s developmental progress. Illustrated with numerous figures and accompanied by a website hosting over 100 video clips, this text is an essential read for professionals in developmental paediatrics, including paediatric physiotherapists, occupational therapists, developmental paediatricians, neuropaediatricians, and paediatric physiatrists