Towards understanding infants' early motor repertoire
Salavati, Sahar
DOI:
10.33612/diss.167712103
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Publication date:
2021
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Salavati, S. (2021). Towards understanding infants' early motor repertoire: the exploration of a diagnostic
and prognostic tool. University of Groningen. https://doi.org/10.33612/diss.167712103
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Chapter
9
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GENERAL DISCUSSION
The aims of this thesis are to describe the infant’s early motor repertoire, its importance for predicting the outcomes of various neurodevelopmental domains across a wide range of ages, and finally, its clinical and predictive value regarding infants with rare diseases in whom spontaneous movements and postures have hardly been studied before. To achieve these aims we used Prechtl’s general movement assessment (GMA), including detailed analyses of movements and postures.
We described the early motor repertoire of very preterm (VP) infants in detail and compared it to the repertoire of healthy term infants. This comparison resulted in reference data (Chapter 2) that are presented in Table 1.
Furthermore, we studied the associations between the early motor repertoire and neurodevelopment and provide a summary of the results in Table 2. We studied motor function and cognition in VP born children (Chapter 3), intelligence and cognition in preterm-born young adults (Chapters 4 and 5), and language outcome in children developing typically (Chapter 6).
Regarding our aim to determine the clinical value of the early motor repertoire in infants with rare diseases, we studied the case of an infant who contracted an intrauterine Human Parechovirus Type 3 (HPeV-3) infection and we report on its neurodevelopment (Chapter 7). In addition, we describe the early motor repertoire of infants diagnosed with inherited metabolic diseases of the intoxication type (IMD-IT) in Chapter 8. We provide the descriptions of their early motor repertoires in Chapters
7 and 8 in Table 1.
Part I. Characteristics of the early motor repertoire
The assessment of the early motor repertoire at the post term age (PTA) of around 3 months is widely used and increasingly implemented in standard clinical care of preterm-born children. Multiple studies have reported on early motor repertoire scores, mostly in relation to motor outcomes.1–3 Unfortunately, the samples sizes in
most studies were small. A relatively large study, in which the motor optimality score (MOS) and subscale scores were presented, included only infants who had developed cerebral palsy (CP).1 Another study reported on MOSs of a large comparison group
of healthy term infants.4 For the purpose of creating the reference data presented
in Chapter 2, we studied the early motor repertoire of 180 VP infants and 180 term infants. We found that the VP infants had poorer MOSs and thus obtained poorer scores on the subscales than healthy term-born infants (Table 1). These findings
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are in line with those of Peyton et al. who reported that for each week’s decrease in gestational age (GA), the odds of aberrant FMs increases by 1.96 (95% confidence level, 1.15-3.35).5 The MOS is strongly determine by the FMs and therefore aberrant
FMs result in lower MOSs. Interestingly, in a study on 82 extremely preterm-born Norwegian infants, Fjørtoft reported a median MOS higher than the score we found in our study.6 One would expect these scores to be lower, because these children were
born at a younger gestational age. On comparing the scores in more detail it appeared that differences in scoring lay in the subscales of observed postural patterns and movement character. It should also be noted that in the study by Fjørtoft et al., scores of healthy controls were also higher than the scores in our controls.6
To enable detailed assessment of preterm infants’ general movements (GMs) and writhing GMs, which results in the GMOS, Einspieler et al. developed percentile scores in addition to the raw scores.7 It would be useful to complement the reference data
for the early motor repertoire at round 3 months of PTA that we provide in Chapter 2 with percentile ranks, while maintaining the distinction between preterm-born and term infants. Consequently, comparing the MOSs and subscale scores of infants born at different gestational ages may become more relevant clinically.
To enable detailed assessment of preterm infants’ general movements (GMs) and writhing GMs, which results in the GMOS, Einspieler et al. developed percentile scores in addition to the raw scores.7 Similarly, it would be useful to augment the reference
data for the early motor repertoire at round 3 months of PTA, which we provide in
Chapter 2, with percentile ranks, while maintaining the distinction between
preterm-born and term infants. In this way comparing the MOSs and subscale scores of infants born at different gestational ages may become more relevant clinically. Moreover, we consider a MOS of 25 or higher as optimal because it comprises approximately 10% of the maximum obtainable score and accounts for the possibility of a minimal score on one of the domains. In three other studies the MOS was dichotomized similarly 1,4,8,
or cut-off at 26 instead of 25 points.9,10 In our opinion, further research into the added
value of dichotomizing the MOS is desirable.
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Ta bl e 1 . D es cr ip tio ns o f t he e ar ly m ot or r ep er to ire i n v ar io us g ro up s o f i nf an ts . Ch. Su bj ec ts GMO S, m ed ia n (p 25 ; p7 5) GM s, n ( % ) M O S, m ed ia n (p 25 ; p 75 ) FM s, n ( % ) O bs er ve d m ov em ent pa tte rn s, n ( % ) Ag e-ad eq uat e m ov em ent re pe rt oi re O bs er ve d po stur al pa tte rn s, n ( % ) M ove m ent ch ar ac te r, n ( % ) 2 GA < 3 0 w k n = 18 0 24 .0 (2 3. 0; 2 6. 0) N A exa gg er at ed Ab se nt 16 3 ( 91 ) 9 ( 5) 8 ( 4) N > A N = A N < A 17 4 ( 97 ) 2 ( 1) 4 ( 2) Pr es en t Red uced Ab se nt 84 ( 47 ) 73 ( 40 ) 23 ( 13 ) N > A N = A N < A 11 9 ( 66 ) 23 ( 13 ) 38 ( 21 ) N A not C S CS 28 ( 16 ) 15 2 ( 84 ) 0 ( 0) He al th y t er m n = 18 0 26 .0 (2 5. 0; 2 8. 0) N A exa gg er at ed Ab se nt 17 6 ( 97 ) 3 ( 2) 1 ( 1) N > A N = A N < A 17 1 ( 95 ) 8 ( 4) 1 ( 1) Pr es en t Red uced Ab se nt 12 7 ( 71 ) 40 ( 22 ) 13 ( 7) N > A N = A N < A 17 3 ( 96 ) 2 ( 1) 6 ( 3) N A not C S CS 94 ( 52 ) 85 ( 47 ) 1 ( 1) 7 HP eV -3 in fe cti on n = 1 22 16 12 a PR CS CS a 8 Ab se nt N > A Ab se nt N < A CS 8 IMD -IT n = 26 30. 0 (2 3. 5; 3 3. 0) N PR CS 4 ( 31 ) 9 ( 69 ) 0 ( 0) 20 .5 (1 3. 8; 2 3. 0) N A exa gg er at ed A n ew ly de sc rib ed v ar ian t Ab se nt 17 ( 64 ) 3 ( 12 ) 3 ( 12 ) 3 ( 12 ) N > A N = A N < A 23 (8 8) 2 (8) 1 (4) Pr es en t Red uced Ab se nt 5 ( 19 ) 14 ( 54 ) 7 ( 27 ) N > A N = A N < A 6 ( 23 ) 4 ( 15 ) 16 ( 62 ) N A not C S CS 1 ( 4) 25 ( 96 ) 0 ( 0) Ab br ev ia tio ns : a, t ra je ct or y fr om pr et er m bi rt h un til te rm ag e; A, ab no rm al ; C h, ch ap te r; CS , c ra m pe d-sy nc hr on ize d; FM s, fid ge ty m ov em en ts ; G A, ge st ati on al ag e; GM s, ge ne ra l m ov em en ts ; H Pe V-3, hu m an pa re ch ov iru s t yp e 3; IM D-IT , i nt ox ic ati on ty pe in he rit ed m et ab ol ic di se as es ; M OS , m ot or op tim al ity s co re ; N , n or m al ; O R, o dd s r ati o; P R, p oo r r ep er to ire ; w k, w ee ks . 136874_Sahar_Salavati_BNW-def.indd 168 136874_Sahar_Salavati_BNW-def.indd 168 19-3-2021 13:37:1419-3-2021 13:37:14
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Part II. Predictive value of the early motor repertoire
Motor development
Generally, motor impairments in infants only become apparent gradually. Signs of hemiplegia, for instance, evolve slowly during the first 24 months.11 This explains
why identifying infants at risk of developing motor impairments at an early stage poses a challenge. Assessing infants’ early motor repertoire has become a widely used method to accommodate this issue.1,12,13 Infants at risk of cerebral palsy are
regularly identified by using this method. Milder motor impairments too have been associated with the early motor repertoire in follow-up studies at different ages, including puberty.14–17 Spittle et al. studied a sample of infants born at less than 30
weeks of gestation and found that the quality of their FMs is associated with better motor performance at two and four years of age.16 In Chapter 3 we present our
follow-up study of these children when they were 8 years old. We found that not only normal FMs, but favourable performance on other aspects of the early motor repertoire too, were associated with better motor performance (Table 2). This implies that motor impairments more subtle than CP can also be identified by assessing the early motor repertoire of very preterm infants.
Intelligence and cognitive development
Based on the concept that the early motor repertoire reflects the integrity of the infant’s central nervous system, domains of brain function other than the motor domain are increasingly being related to the early motor repertoire.18–21 This may be
best understood with VP infants as an example. Very preterm infants are known to be at risk of cognitive problems that occur either together with motor problems or in isolation.22 These problems have been related to white matter injury and other brain
abnormalities.23 Severe white matter injury in turn has been correlated to aberrant
writhing GMs and FMs.5,24 In asphyxiated infants such correlations were also found
for basal ganglia and thalamic lesions.25 Moreover, Peyton et al. found that proper
connectivity is needed for infants to perform variable and fluent spontaneous movements. They found evidence that aberrant GMs are associated with decreased resting state functional connectivity between the basal ganglia and parietal and frontotemporal lobes.26 These findings are not surprising when we take into
consideration that cognitive development largely depends on the integrity of diffuse neural networks.27 Put differently, the presence of brain abnormalities and resulting
functional problems later in life are already likely to be reflected by abnormalities in the early motor repertoire.16,21
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To elaborate on this concept, we studied associations between the early motor repertoire and cognition in 8-year-old, VP children in Chapter 3. As is described in more detail in Table 2, we found strong evidence of associations between favourable early motor repertoire scores and better cognition in childhood. These findings are in line with those of previous studies.28
Regarding our interest in whether associations between infants’ early motor repertoire and neurodevelopment persist into young adulthood, we performed a longer follow-up study on intelligence and cognition. We report the findings in Chapters 4 and
5. In Table 2 we indicate that the absence of FMs in particular is associated with
poorer intelligence and various impaired cognitive functions. Evidence for these associations with intelligence and cognition into young adulthood (Chapters 4 and 5) was weaker than for childhood (Chapter 3). For instance, we found evidence that a favourable performance on the MOS and its subscales was associated with better attention in childhood. No such associations, however, were found for our study in young adulthood. These differences may be caused by the effect of the longer time span until follow-up combined with possible interference from environmental factors. Furthermore, the degree of prematurity and sample sizes differed between the studies. It may well be that as a result of the lack of power in the studies we present in Chapters 4 and 5 that the evidence was weaker.
Our study on writhing GMs is presented in Chapters 4 and 5 and the findings were inconclusive. Of this type of GMs it is known that they can normalize over time and therefore one should be cautious about drawing conclusions regarding outcome based on the quality of these GMs.2,12
Language development
The development of language is another domain of interest in which problems or delay may occur. Language acquisition is complex and associated with to cognition.29
In Chapter 6 we report that in children who are developing typically, a smooth and fluent movement character as well as a higher MOS in infancy were associated with better expressive language in childhood, whereas the predominance of normal postural patterns was associated with poorer expressive language (Table 2). To the best of our knowledge, these associations have not been studied before. Nevertheless, because language skills are to some extent associated with cognition, we may consider these associations found in a sample of healthy infants, even with minimal variation in the early motor repertoire, to be consistent with previous research. This interpretation, however, does remain speculative.
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General remarks
Based on the evidence from a wide variety of studies, we hypothesize that infants’ early movements and postures reflect the integrity of their central nervous system. We also hypothesize that early development requires environmental input and interaction. A lack of appropriate environmental input at an early stage restricts development. Various studies have reported associations between deprived sensory input and poorer outcomes in the domains related to that sensory input.30–32 Integration in the
infant brain of motor, sensory, and visual input is thought to be influenced by FMs.33
We speculate that abnormalities in the early motor repertoire such as the absence of FMs hamper the exploration of the environment and thereby the formation of new neural connections is limited. Increasingly, current research is disclosing associations between the early motor repertoire and various developmental domains 1,15,18,19,28.
We therefore agree with Spittle et al. who advise that aberrancies in the early motor repertoire can have implications for different areas of development other than motor performance alone and they urge clinicians to be aware of this fact.16
In comparison to diagnostic methods like magnetic resonance imaging 13, FMs are a
reliable predictor of CP. Nevertheless, this method has its limitations. Based on the risk of false positives, Kwong et al. argue that the assessment of FMs for predicting CP should not be used in isolation, but to rather use them in combination with other diagnostic methods.2 In addition, it seems that the strength of the predictive value
of FMs is limited when less severe types of motor impairments are studied.15 The
same may be true for determining intelligence, cognitive, and language outcomes, particularly when studied in healthy term-born infants.34 In the case of such infants,
however, one should keep in mind that by nature the prevalence of abnormalities in early movements and postures is low.4,6 This does not alter the fact that the early
motor repertoire can be used for risk assessment and that it provides some indication of the expected course of neurodevelopment.
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Ta bl e 2 . A ss oc ia tio ns b et w ee n t he e ar ly m ot or r ep er to ire a nd n eu ro de ve lo pm en t i n v ar io us g ro up s o f i nf an ts . Ch. Su bj ec ts Ag e fo llo w -up ( y) Ea rly m ot or re pe rt oi re As so ci ati on s M oto r In te lli ge nc e Att en tio n M em or y In fo rm ati on pr oce ss in g sp ee d Ex ec utiv e fun cti on Lan gu ag e 3 GA < 3 0 w k n = 78 8 M OS ↑ ↑ B 0 .5 5 ( 0. 37 -0.7 3) ↑ ↑ B 1 .7 5 ( 1. 23 ; 2. 28) ↑ ↑ s us ta in ed atte nti on B 0 .2 6 ( 0. 08 6; 0 .4 3) ↑ ↑ s el ec tiv e atte nti on B 0 .2 6 ( 0. 08 8; 0 .4 4) ↑ ↑ i m m ed ia te ve rb al m em or y B 1 .5 9 ( 0. 65 ; 2 .5 3) ↑ ↑ v er ba l w or ki ng m em or y B 1 .2 5 ( 0. 46 - 2 .0 5) = FM s Ab se nc e ↓ Ab se nc e ↓ Ab se nc e ↓ sus ta ine d att en tio n = = O th er sub sc al es a ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑ ↑ 4 & 5 GA < 3 5 w k or B W < 1 20 0 g n = 37 21 - 2 7 W rithi ng G M s = Ab no rma l ↑ = = = = M OS ↑ ↑ B 0 .7 4 ( 0. 02 8; 1. 45 ) ρ 0 .3 4 = = = ↑ ↑ ρ 0 .4 5 = FM s Abs en ce ↓ = Ab no rm al ↓ Ab se nc e ↓ Ab se nc e ↓ Ab no rm al or a bs en ce ↓ Ab no rm al or a bs en t ↓ = 6 Ty pi call y dev el op in g n = 22 4 M OS ↑ ↑ e xp re ss iv e lan gu ag e B 1 .0 ( 0. 16 ; 1 .8 3) M ove m ent ch ar ac te r No rm al ↑ ex pr es siv e l an gu ag e 10 M OS ↑ ↑ e xp re ss iv e lan gu ag e B 0 .3 0 ( 0. 16 ; 0 .4 9) M ove m ent ch ar ac te r No rm al ↑ ex pr es siv e l an gu ag e Po stur al pa tte rn s No rm al ↓ ex pr es siv e l an gu ag e Ab br ev ia tio ns : = , n o as so cia tio ns fo un d; ↑ , h ig he r s co re ; ↓ , l ow er sc or e; a, s ig ni fic an t a ss oc ia tio ns fo r m os t M OS su bs ca le s; B (9 5% C I), u ns ta nd ar di ze d co effi ci en t t ha t r ep re se nt s c ha ng e in de pe nd en t v ar ia bl e pe r u ni t c ha ng e in M OS , i nc lu di ng 95 % co nfi de nc e in te rv al ); BW , b irt h w ei gh t; Ch , c ha pt er ; FM s, fi dg et y m ov em en ts ; G A, g es ta tio na l a ge ; G M s, g en er al m ov em en ts ; ρ , S pe ar m an ’s r ho ; w k, w ee ks . No te : t he r es ul ts i n C ha pt er s 3 a nd 6 w er e c or re ct ed f or c on fo un di ng f ac to rs , w hi le t hi s w as n ot t he c as e f or t he r es ul ts i n C ha pt er s 4 a nd 5 . 136874_Sahar_Salavati_BNW-def.indd 172 136874_Sahar_Salavati_BNW-def.indd 172 19-3-2021 13:37:1519-3-2021 13:37:15
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Part III. Exploration of the scope of the assessment of the early motor
rep-ertoire
Over the past decades, assessment of the early motor repertoire has been utilized as a diagnostic method in various groups of infants, most of whom were at high risk of neurodevelopmental problems. We extended the scope of this method by adding evidence regarding infants who contracted an intrauterine infection and infants suffering from an inherited metabolic disease.
An infant with intrauterine Human Parechovirus Type 3 infection
Intrauterine infections can interfere with normal foetal brain development.35
Consequently, just as in the case of preterm infants, infants who contracted an intrauterine infection are generally at increased risk of neurodevelopmental problems. Therefore predicting outcomes is of the utmost importance. Einspieler et al. studied infants who had been exposed to the Zika virus in utero and concluded that their early motor repertoire accurately predicted neurodevelopmental outcomes at 12 months.4 Another viral infection that is increasingly recognized as an important
cause of illness in infants is HPeV-3 36, the vertical transmission of which has not
been reported previously. Outcomes may vary and range from normal to severe neurological sequelae.37–41 When we encountered a case of HPeV-3 infection
that presumably originated from an intrauterine infection, we were ignorant as to the child’s outcome. In Chapter 7 we report that the quality of the infant’s GMs gradually deteriorated from poor repertoire to cramped-synchronized and that, subsequently, FMs remained absent (Table 1). Ultrasound and magnetic resonance imaging confirmed cerebral involvement. Follow-up at approximately 2 years of PTA revealed poor neurodevelopment. We consider this case to be an example of the invaluable practical significance of this assessment tool in routine clinical care. We speculate that the timing of an intrauterine infection, for instance, during the early migration phase or the myelination phase later on 42, may determine the severity of
its neurodevelopmental sequelae. The early motor repertoire of the HPeV-3 case under consideration could be distinguished from the early motor repertoires of infants during the acute phase of a postnatal systemic infection without cerebral involvement. In the latter cases the infants’ movements and postures retained their complexity, but became sluggish.43
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Infants with inherited metabolic diseases of the intoxication type
Children with IMD-IT are at risk of poor neurodevelopment.44 As a result of a
metabolic error toxic metabolites accumulate in the brain and cause damage. Consequently, cerebral functions are affected.44,45 To date, our understanding of the
neurodevelopmental course of a child with IMD-IT is, however, minimal because of considerable clinical heterogeneity between and within types of IMD-IT. In Chapter
8 we describe the early motor repertoire in a sample of IMD-IT infants and often
found their repertoires to be abnormal. Furthermore, we recognized a hitherto undescribed type of abnormal FMs. Previously, disease-related features of the early motor repertoire had been identified in infants with dyskinetic CP.46 Unfortunately,
we were unable to establish the accuracy of the predictive value of the early motor repertoire for IMD-IT patients’ neurodevelopment is accurate.
Because infants with IMD-IT often show encephalopathic features on brain imaging
47, it may be that combining brain imaging and the assessment of the early motor
repertoire is better than using either method in isolation. Similarly, Ferrari et al. recommended that diagnosing CP in infants may best be done by using a combination of early motor repertoire assessment and brain imaging.25 Future prospective research
on the associations between MRI, the early motor repertoire, and outcome data may confirm these thoughts. Furthermore, an in-depth understanding of the predictive value of the early motor repertoire for neurological development is indispensable.
General remarks
The data presented in Chapters 7 and 8 indicate that it is appropriate to assess the early motor repertoire of infants who contracted an intrauterine viral infection and in infants with IMD-IT. Even though the aetiology of these diseases differ from the many possible causes of prematurity, our understanding is that brain aberrations in all these infants have a common ‘end point’ - the spontaneous movements and postures of the early motor repertoire - that reflects the disrupted integrity of the central nervous system.
FUTURE PERSPECTIVES AND IMPLICATIONS
To deepen our understanding of the early motor repertoire of infants and its usefulness in clinical care, further research on several domains is required. Suggestions for research in the domain of brain plasticity and early intervention and its relevance to clinical care is discussed below.
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Brain plasticity and early interventions
The necessity of the early recognition of the risks of poor neurodevelopment lies with the phenomenon of brain plasticity. The infant brain is uniquely equipped to adapt to unfavourable circumstances. This is illustrated by the circumstance of unilateral brain damage that results in hemiplegia. Initially, in healthy infants corticospinal projections are bilateral. Gradually, however, the ipsilateral fibres disappear and only the contralateral fibres remain. This process depends on use and activity. In case of unilateral brain damage, the disappearance of ipsilateral fibres is detrimental and causes functional limitations. With the help of constraint induced therapy, ipsilateral fibres are retained and thereby motor outcome improves.48,49 It is important to note
that the timing of brain injury and intervention seem crucial to the questions whether and to what extent the brain will display its plasticity.50 For various brain functions
critical periods have been identified.51,52 These are characterized by maximum
sensitivity of neural networks to environmental influences. Cioni et al. theorize that interventions during this critical period enhance plasticity and thereby outcome improves.53
Further research into the neural networks responsible for spontaneous movements and postures in infants may help us understand how externally visible abnormalities are associated with brain aberrancies and, ultimately, with poor neurodevelopmental outcomes. More precise associations between aberrations in specific brain structures or networks, the early motor repertoire, and outcomes may be identified. The current extent of our knowledge is that appropriate neuronal brain connectivity is essential for variable and fluent spontaneous movements and postures in infancy.26
Various studies have reported on the effects of early interventions that aim to improve neurodevelopmental outcomes of infants at risk of poor neurodevelopment.54,55 It has
been reported that beneficial effects persists until pre-school age.54 However, results
on outcomes at school-age or later are heterogeneous. The timing of intervention may play an important role.56,57 It has been suggested that interventions may be
most effective until one and a half years of age.55 Recently, three studies reported on
physiotherapy interventions until 19 weeks of PTA and the resulting positive effects on the quality of infants’ GMs and FMs.58–60 Advances are also made in intervention
programmes for VP children at school age, but to date results are limited.61 We
conclude that further research into the optimal timing of intervention in relation to the critical periods of development is required.
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Implementation in clinical care
Even though the assessment of the early motor repertoire as a diagnostic method is applied increasingly often, its use is generally limited to research purposes. In our opinion, many infants at risk of poor neurodevelopment may benefit from implementing the method in standard clinical care. In the Netherlands, over the past years, follow-up of an important group of infants at risk of poor development, i.e. preterm infants, has improved and is extended to the age of 8 years.62 This was
done after it became clear that neurodevelopmental problems are likely to persist throughout childhood and even into adulthood.63–66 Implementing the assessment
of the early motor repertoire in standard clinical care will enable health care professionals to identify infants at risk of neurodevelopmental problems and to provide early intervention strategies for these infants.
To provide worldwide access to the assessment of the early motor repertoire, irrespective of resources, various approaches have been initiated and should be developed further. The global working group BornTogetThere focuses on early detection, early surveillance, and early intervention for infants who are at risk of CP and for whom the assessment of the early motor repertoire plays an important role.67 Another initiative is the general movement assessment in neonates for early
identification and intervention, social support and health awareness (GANESH). It aims to investigate the possibilities of community health workers to use the assessment of GMs in low-resource settings in India.68
Furthermore, smartphone applications such as GMapp and the Baby Moves have been developed to enable parents to easily obtain and safely transfer their infant’s video recordings to health care professionals.69,70 It is important to note is that the
Baby Moves app was used less by families with a lower socio-demographic status than in families with a higher socio-demographic status.69 This requires further
research into the social aspects of the use of the app.
Another technical development that would help improve the accessibility of the method is automated analysis. It would solve the issues of time-consuming analysis and the availability of fully-trained and skilled assessors. Several advances have been made in the direction of automated analysis using various methods.5,71–73 To date, no
method has been designed that can automatically score the complete early motor repertoire. Nevertheless, if only a triage of infants at risk of poor development could be implemented, that would already be a great benefit.
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Conclusions
This thesis helps to improve our insight into the value and applicability of the early motor repertoire as a diagnostic tool. The increased risk of poor neurodevelopment as a result of preterm birth, intrauterine infection, or inherited metabolic diseases is reflected by poorer scores on the early motor repertoire in infancy. Using the assessment of the early motor repertoire as a predictor for neurodevelopment, it may well be used in those infants at risk of poor outcomes in the motor, intelligence, cognitive and language domains. We found less evidence for its applicability in healthy term infants in whom, by nature, the prevalence of abnormalities in early movements and postures is low. Hopefully, the content of this thesis shall contribute to the improvement of early, targeted intervention and ultimately to the improved outcomes of infants at risk of poor neurodevelopment.
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