Early Detection and Early Intervention in Developmental Motor Disorders: From Neuroscience to Participation

PART I

Introduction

Chapter 1 Introduction

Chapter 2 Early Diagnosis and Early Intervention in the Clinic

Introduction

Mijna Hadders-Algra

This book provides an overview of early detection and early intervention in developmental motor disorders. Developmental motor disorders are defined as disorders characterized by limitations in mobility due to an altered organization of the brain that had its origin in early life. This definition has two main components. The first component consists of the limitations in mobility. Mobility is the term of the International Classification of Functioning, Disability and Health, Children & Youth version (ICF-CY) to describe activities and participation with a motor component (World Health Organization 2007; Fig. 1.1). Examples are changing and maintaining body position; moving around

and walking; and carrying, moving, and handling objects. The second component is the altered organization of the brain originating in early life. The altered organization may consist of a congenital malformation, a prenatal, perinatal, or neonatal lesion of the brain, or a more subtle disruption of the developmental processes occurring in the brain during the prenatal, perinatal, and neonatal period (Hadders-Algra 2018).

So far, so good. However, at an early age it is generally not easy to determine which infant will be diagnosed later with a developmental motor disorder. In clinical practice, the diagnostic trajectory often starts with a careful monitoring of infants who are at high risk for developmental disorders, for instance infants who had been critically ill in the newborn period, such as infants born preterm, or infants with intrauterine growth retardation, hypoxic-ischaemic encephalopathy, a complex congenital heart disease, or a lesion of the brain. It is well known that these infants are at high risk of developmental disorders, including motor disorders (Mercuri and Barnett 2003; De Kieviet et al. 2009; Miller et al. 2016; Van Iersel et al. 2016; Huisenga et al. 2020). But not all high risk infants have an impaired outcome (e.g. about half of the preterm infants have a favourable outcome). In addition, a substantial proportion of children with a developmental disorder has an uneventful prenatal, perinatal, and neonatal history. Part V of this book addresses how we best can detect the infants at high risk for developmental motor disorders.

In older children, two groups fulfil the criteria of developmental motor disorder. First, children with cerebral palsy (CP), who have limited mobility due to a congenital malformation or an early lesion of the brain (see Text Box 1.1). Second, children with developmental coordination disorder (DCD; see Text Box 1.2). Children with DCD also have a limited mobility, but mostly the limitations are less marked than those in children with CP. In the majority of children with DCD, no evident lesion of the brain can be demonstrated. However, neuroimaging studies suggest that the brains of these children exhibit minor alterations in organization (Peters et al. 2013; Wilson et al. 2017; Brown-Lum et al. 2020).

Figure 1.1 Diagram of the ICF-CY. The diagram illustrates the dynamic interactions between the various entities determining a child’s health condition and his activities and participation.

Text Box 1.1 Cerebral Palsy

Cerebral palsy has been defined as ‘a group of permanent disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing foetal or infant brain. The motor disorders of cerebral palsy are often accompanied by disturbances of sensation, perception, cognition, communication, and behaviour, by epilepsy and by secondary musculoskeletal problems’ (Rosenbaum et al. 2007, p. 9).

Rosenbaum (2014) highlighted that:

• The focus of the definition is on limitations in activities and participation and not on impairments in body structure and function.

• CP is a developmental disorder, implying that the permanent disorder originating in early life is characterized by changes in clinical manifestation over the lifetime.

• CP is characterized by heterogeneity in clinical manifestation (i.e. by variation in signs, severity, and co-morbidity).

To cope with the heterogeneity in the manifestation of CP, functional classification systems have been developed to characterize the individual’s gross motor function (Gross Motor Function Classification System; GMFCS; Palisano et al. 1997), manual ability (Manual Ability Classification System, MACS; Eliasson et al. 2006), communication (Communication Function Classification System, CFCS; Hidecker et al. 2011), feeding and eating (Eating and Drinking Ability Classification System, EDACS; Sellers et al. 2014), and visual function (Visual Function Classification System, VFCS; Baranello et al. 2020). In addition, the clinical manifestation of CP can be described using the distribution of neurological impairments: spastic CP (unilateral or bilateral), ataxic CP, or dyskinetic CP (Rosenbaum 2014).

Text Box 1.2 Developmental Coordination Disorder

The diagnostic criteria of developmental coordination disorder (DCD) described in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5, American Psychiatric Association 2013) are:

A. The acquisition and execution of coordinated motor skills is substantially below that expected given the individual’s chronological age and opportunity for skill learning and use. Difficulties are manifested as clumsiness (e.g. dropping or bumping into objects) as well as slowness and inaccuracy of performance of motor skills (e.g. catching an object, using scissors or cutlery, handwriting, riding a bike, or participating in sports).

B. The motor skills deficit in Criterion A significantly and persistently interferes with activities of daily living appropriate to chronological age (e.g. self-care and self-maintenance) and impacts academic/school productivity, prevocational and vocational activities, leisure, and play.

C. Onset of symptoms is in the early developmental period.

D. The motor skills deficits are not better explained by intellectual disability (intellectual development disorder) or visual impairment and are not attributable to a neurological condition affecting movement (e.g. CP, muscular dystrophy, degenerative disorder).

At an early age, children with CP and DCD do not fulfil the diagnostic criteria of their disorders. Due to the substantial developmental changes occurring in the brain during the first postnatal years (see Chapter 3), it takes developmental time before the disorders become fully expressed. Generally, CP is first diagnosed from about the end of the first postnatal year onwards, whereas in some children it may take several years before the clinical picture is established (Smithers-Sheedy et al. 2014; Granild-Jensen et al. 2015). DCD is typically not diagnosed before the age of 5 years (Blank et al. 2019). However, the last version of the Diagnostic and Statistical Manual of Mental Disorders (i.e. its fifth edition [DSM-5]) introduced for the diagnosis of DCD the new criterion that the symptoms start in the early developmental period (criterion C, Text Box 1.2). Yet, the evidence supporting this criterion is limited.

Developmental motor disorders are the main theme of the book. It should be realized, however, that developmental disorders usually are not restricted to limitations in one domain. For instance, limitations in mobility are often accompanied by limitations in learning and communication. Two major factors explain the high rate of limitations in multiple domains: (1) adversities that interfere with early brain development generally do not affect single functional systems; (2) the high degree of interrelation between development in the various domains. For instance, limited mobility hampers the infant’s discovery of the world, which, in turn, negatively impacts cognitive development and, vice versa, limitations in learning (e.g. in exploratory drive) interfere with motor development.

The book zooms in on the prenatal period and the first 2 years post-term – the first 1000 days of life. It uses the ICF-CY as framework of reference. The ICF-CY emphasizes that activities and participation in daily life do not only depend on body function and structure, but also environmental and personal factors (Fig. 1.1). What the latter may imply is recounted in the reflections on disability presented in Text Box 1.3. The book starts with the clinical picture of early detection and early intervention. Next, in Part II, the neurodevelopmental mechanisms occurring in early life are discussed, including vulnerability and plasticity. Part III comprises chapters on typical development. It not only discusses motor development but also sensory and cognitive development. It is increasingly recognized that motor development is strongly interrelated with developmental changes in other brain functions (Diamond 2000). The strong interrelation explains why children with developmental motor disorders often have comorbid disorders, such as learning disorder, autism spectrum disorder, and attention deficit and hyperactivity disorder (Novak et al. 2012; Blank et al. 2019). Part IV discusses atypical motor development. After the preparatory chapters of Parts I to IV, the heart of the matter follows: Part V provides an overview of the methods available for early detection, and Part VI summarizes early intervention methods, including their evidence on effectiveness. Special attention is paid to the family (Chapter 12) and environmental adaptations (Chapter 15).

Text Box 1.3 Reflections About Disability – A Personal Point of View

• Disability or different abilities? Why do we characterize persons with a disability by their disability? Is it because the disability is frequently quite visible? Are we scared by this view as the disability confronts us with the vulnerability of human existence? What prevents us from being open to the idea that everybody has different abilities, everybody has strengths and weaknesses? Isn’t being able to share a smile when the sun warms the skin and the wind strokes the hair equally valuable as being able to write a chapter?

• Walking or wheeling? Families and professionals often choose as a major goal of early intervention the achievement of the ability to walk (independently). Of course, I won’t deny that it is convenient to be able to walk without help. However, when the walking costs an enormous effort, it is perhaps better to skip this activity and save the energy for communication, other forms of social interaction, learning and applying knowledge. I learnt this well from personal experience. I acquired a partial spinal cord lesion at the age of 16 years. The physicians doubted whether I would be able to walk again. However, being somewhat on the hyperactive side of the spectrum, I massively practised and regained the ability to walk. Over time, the walking deteriorated and I realized how much upright stance and walking interfered with communication and cognitive function. When I started to use the wheelchair, I ‘regained my brain’.

• Interdependency. Disability is associated with dependency (i.e. a condition that is the opposite of autonomy and independency that are advocated as ultimate goals for individuals in Western industrialized societies). Actually, I think, that the Western societies can learn from other societies, such as the Asian and African societies that focus more on interdependency (Nisbett and Miyamoto, 2005). These societies acknowledge more than the Western that humans are social beings, with a brain that is totally tuned to interaction with others (Chen et al. 2018). The interdependency implies that all humans depend on other human beings. In general, we consider it as typical that we depend on the pilot of an aircraft when we fly, or on the employees of a supermarket when we go shopping, but we feel embarrassed by the idea that we might need assistance when visiting the bathroom. Again, from personal experience, dependency in this situation does not differ from that in the other ones. You just get confirmation that the large majority of fellow humans are friendly and respectful, and that humans indeed are social beings.

• Assistive devices. Families and professionals may have a negative view on assistive devices, as they underline that the infant has specific impairments or limitations. But we perhaps should try to root out this view, as assistive devices are meant to do what their name tells: to assist, to make life easier. It is interesting to consider the change over the last five decades in the perception of the visual assistive device ‘glasses’. Fifty years ago, wearing glasses was regarded as negative; children with glasses were called names and bullied. However, nowadays glasses have an entirely positive aura; they are part of fashion and used to express a person’s identity.

Finally, two practical remarks. First, the infant ages used in this manual always refer to ages corrected for preterm birth, unless otherwise indicated (e.g. foetal ages and gestational ages of preterm infants). This is not further indicated in the text. Second, writing about individuals who may be male or female gives an author the awkward choice of consistent referral to all gender typologies by using expressions such as he/she, or the selection of a specific gender. The latter results in a text that is easier to read, but this option has the disadvantage that an impression of ‘neglect’ of other gender identities occurs. We opted for a single gender option to facilitate readability, and choose the female gender when referring to the professional and the male gender when referring to the child. However, we would like to stress our gender-neutral intentions.

REFERENCES

American Psychiatric Association (2013) Diagnostic and Statistical Manual of Mental Disorders, 5th edn. Washington DC: American Psychiatric Association.

Baranello G, Signorini S, Tinelli F, et al. (2020) Visual Function Classification System for children with cerebral palsy. Dev Med Child Neurol 62: 104–110. doi: 10.1111/dmcn.14270.

Blank R, Barnett AL, Cairney J, et al. (2019) International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder. Dev Med Child Neurol 61: 242–285. doi: 10.1111/dmcn.14132.

Brown-Lum M, Izadi-Najafabadi S, Oberlander TF, Rauscher A, Zwicker JG (2020) Differences in white matter microstructure among children with developmental coordination disorder. JAMA Netw Open 3: e201184.

doi: 10.1001/jamanetworkopen.2020.1184.

Chen C, Martínez RM, Cheng Y (2018) The developmental origins of the social brain: empathy, morality and justice. Front Psychol 9: 2584. doi: 10.3389/fpsyg.2018.02584.

De Kieviet JF, Piek JP, Aarnoudse-Moens CS, Oosterlaan J (2009) Motor development in very preterm and very low-birth-weight children from birth to adolescence: a meta-analysis. JAMA 302: 2235–2242. doi: 10.1001/jama.2009.1708.

Diamond A (2000) Close interrelation of motor development and cognitive development and of the cerebellum and prefrontal cortex. Child Dev 71: 44–56.

Eliasson AC, Krumlinde-Sundholm L, Rösblad B, et al. (2006) The Manual Ability Classification System (MACS) for children with cerebral palsy: scale development and evidence of validity and reliability. Dev Med Child Neurol 48: 549–554.

Granild-Jensen JB, Rackauskaite G, Flachs EM, Uldall P (2015) Predictors for early diagnosis of cerebral palsy from national registry data. Dev Med Child Neurol 57: 931–935. doi: 10.1111/dmcn.12760.

Hadders-Algra M (2018) Early human brain development: starring the subplate. Neurosci Biobehav Res 92: 276–290. doi: 10.1016/j.neubiorev.2018.06.017.

Hidecker MJ, Paneth N, Rosenbaum PL, et al. (2011) Developing and validating the Communication Function Classification System for individuals with cerebral palsy. Dev Med Child Neurol 53: 704–710. doi: 10.1111/j.1469-8749.2011.03996.x.

Huisenga D, La Bastide-Van Gemert S, Van Bergen A, Sweeney J, Hadders-Algra M (2020) Developmental outcomes after early surgery for complex congenital heart disease: a systematic review and meta-analysis. Dev Med Child Neurol, Epub ahead of print. doi: 10.1111/dmcn.14512.

Mercuri E, Barnett AL (2003) Neonatal brain MRI and motor outcome at school age in children with neonatal encephalopathy: a review of personal experience. Neural Plast 10: 51–57.

Miller SL, Huppi PS, Mallard C (2016) The consequences of fetal growth restriction on brain structure and neurodevelopmental outcome. J Physiol 594: 807–823. doi: 10.1113/JP271402.

Nisbett RE, Miyamoto Y (2005) The influence of culture: holistic versus analytic perception. Trends Cogn Sci 5: 467–473.

Novak I, Hines M, Goldsmith S, Barclay R (2012) Clinical prognostic messages from a systematic review on cerebral palsy. Pediatrics 130: e1285–1312. doi: 10.1542/peds.2012-0924.

Palisano R, Rosenbaum P, Walter S, Russell D, Wood E, Galuppi B (1997) Development and reliability of a system to classify gross motor function in children with cerebral palsy. Dev Med Child Neurol 39: 214–223.

Peters LH, Maathuis CG, Hadders-Algra M (2013) Neural correlates of developmental coordination disorder. Dev Med Child Neurol 55 (Suppl 4): 59–64. doi: 10.1111/dmcn.12309.

Rosenbaum P (2014) Definition and clinical classification. In: Dan B, Mayston M, Paneth N, Rosenbloom L, editors, Cerebral Palsy: Science and Clinical Practice. London: Mac Keith Press, pp. 17–26.

Rosenbaum P, Paneth N, Leviton A, et al. (2007) A report: the definition and classification of cerebral palsy, April 2006. Dev Med Child Neurol 49 (Suppl 2) 8–14.

Sellers D, Mandy A, Pennington L, Hankins M, Morris C (2014) Development and reliability of a system to classify the eating and drinking ability of people with cerebral palsy. Dev Med Child Neurol 56: 245–251. doi: 10.1111/dmcn.12352.

Smithers-Sheedy H, Badawi N, Blair E (2014) What constitutes cerebral palsy in the twenty-first century? Dev Med Child Neurol 56: 323–328. doi: 10.1111/dmcn.12262.

Van Iersel PA, Algra AM, Bakker SC, Jonker AJ, Hadders-Algra M (2016) Limitations in the activity of mobility at age 6 years after difficult birth at term: prospective cohort study. Phys Ther 96: 1225–1233. doi: 10.2522/ptj.20150201.

Wilson PH, Smits-Engelsman B, Caeyenberghs K, et al. (2017) Cognitive and neuroimaging findings in developmental coordination disorder: new insights from a systematic review of recent research. Dev Med Child Neurol 59: 1117–1129. doi: 10.1111/dmcn.13530.

World Health Organization (2007) International Classification of Functioning, Disability and Health, Children & Youth Version (ICF-CY). Geneva: WHO Press.

SUGGESTIONS FOR FURTHER READING

Dan B, Mayston M, Paneth N, Rosenbloom L (2014) Cerebral Palsy: Science and Clinical Practice. London: Mac Keith Press.

Graham HK, Rosenbaum P, Paneth N, et al. (2016) Cerebral palsy. Nat Rev Dis Primers 2: 15082. doi: 10.1038/nrdp.2015.82.

Early Diagnosis and Early Intervention in the Clinic

Leena Haataja

SUMMARY POINTS

• The age at which typically developing infants attain various milestones varies widely. This makes early diagnostics of developmental disorders into a challenging task.

• The use of formal developmental screening tools and validated neuromotor and neurological examination tools improves early identification of motor disorders.

• Early clinical signs of cerebral palsy (CP) are not unequivocally specific for CP. Instead, these signs are manifestations of any injury, disorder, or dysfunction of the central nervous system.

• Early detection of CP is based on a combination of detailed patient history, validated neurological examination, or neuromotor assessment and brain imaging.

• Consider the possibility of an alternative condition mimicking CP if the clinical presentation and/or history is unusual and/or neuroimaging is negative.

• Early intervention in infants with or at high risk of CP is associated with short term better outcomes in child and family. No evidence is available on the long term effects of early intervention in children with CP.

Early detection and intervention are clinically relevant for infants who are at high risk of a developmental disorder. There is no internationally agreed consensus definition of the ‘high-risk’ of infants but expert recommendations are available (https://newborn-health-standards.org/). It is agreed that preterm children born <32 weeks of gestation have a higher risk of developmental disorders than infants born at later gestation. Also, infants who are born at or after 32+0 gestation and have one or more significant risk factors are regarded as being at high risk of long-term disability. Examples of significant risk factors are brain injuries verified with neuroimaging, such as grade III intraventricular haemorrhage and venous infarction, hypoxic ischaemic encephalopathy grade II/III, neonatal sepsis or meningitis, foetal growth restriction or being born small for gestational age, and severe social or other serious family problems exposing child to the risk of deprivation and violence.

Early detection of developmental problems relies on a combination of detailed patient history, developmental assessment, structured and validated neurological examination or neuromotor assessment, brain imaging, and further aetiological investigations (e.g. neurophysiological or genetic investigations) when appropriate for differential diagnostics. Delay in early motor development is often the decisive feature leading to further investigations, but the delay itself doesn’t provide direct aetiological support for neurological diagnostics (e.g. for CP). Therefore, a neurological examination is needed. This examination aims to delineate objective neurological findings that correlate with the neuroanatomy of the possible lesion of the central nervous system. Accordingly, the neurological assessment furnishes relevant information for differential diagnostics and future prediction in the clinical context.

Irrespective of the applied methods of neurological and neurodevelopmental examination, specific features of the rapidly developing young nervous system must be recognized as an integral part of the diagnostic process. Accordingly, in most situations longitudinal follow-up examinations are required to comprehend the evolution of the neurological, cognitive, and behavioural findings in an infant.

The major developmental motor disorders in childhood are CP and developmental coordination disorder (DCD). CP has prevalence of two cases per 1000 livebirths in high-income countries (Himmelmann and Uvebrant 2014), though the prevalence is presumably higher in low-income countries. DCD is the most common non-CP motor disorder in childhood with prevalence estimates of 5–6% (Blank et al. 2019). Both in CP and DCD, motor problems interfere with independent age-appropriate activities of daily living and participation. A male predominance is a constant finding across studies both in CP and DCD, and the risk of developing CP or DCD is higher the lower the gestational age at birth is (Sellier et al. 2015; Blank et al. 2019). In contrast to CP, the formal diagnosis of DCD under the age of 5 years is recommended only in cases of severe impairment since young children with motor delay may show spontaneous catch-up. Also the young child’s collaboration and motivation to perform functional tests may cause problems in interpretation and reliability of the diagnostics (Blank et al. 2019).

The current chapter focuses on CP since the clinics of CP during the first two postnatal years well illustrate the possibilities and challenges of early diagnostics and early intervention. First, the definition, clinical spectrum, and classification of CP is discussed. The second section addresses clinical practice with the use of evidence-based examinations aiming at early identification of high risk of CP and diagnostics. In the third section, the role of brain imaging as a part of clinical workup of early diagnostics is discussed. The last section addresses the accumulating research evidence on early intervention and its application to clinical settings at present. However, before we move to these sections, we first meet Mesi. Mesi’s history illustrates the challenges and possibilities in early detection and early intervention. In Mesi’s history the family plays a large role. However, more recently, the role of the family has increased even more, emphasizing the role of family autonomy (see Chapters 12–14).

CASE HISTORY: MESI

‘She is three years of age and she is such a joyful little girl!’ said Mesi’s mum today on the phone. Things were very different when Mesi was born from a twin pregnancy at 26+1 weeks of gestation, 4 weeks after premature rupture of membranes ending with chorioamnionitis. Her size was appropriate for gestational age (birth weight 760g), but she was born in a very poor condition with Apgar scores of 1/1/1 (at 1, 5, and 10 minutes). Immediately after birth, she developed severe hypoventilation problems, so severe that her survival was questioned. The first cranial ultrasound did not show any definite abnormalities, but at 2 weeks of age intraventricular haemorrhage grade I was seen on the right side and a venous infarction on the left side. She did not develop hydrocephalus and she did not have any seizures. Due to severe bronchopulmonary dysplasia (BPD), it was impossible to take a brain magnetic resonance imaging (MRI). Mesi developed stage I retinopathy of prematurity that did not require treatment. At the age of 3 months corrected age (CA), she was discharged from the hospital with an oxygen concentrator that she continued to need during the following 3 months.

During her stay in the neonatal ward, Mesi received physiotherapy once a week that aimed to enhance her tolerance to sensory stimuli and to balance her increased extensor tone and tendencies to asymmetry. The parents and responsible nurses took part in the therapy sessions, so that the intervention strategies could be integrated in the daily care-giving activities. When Mesi was discharged from the hospital, the parents received additional advice on how to take care of their daughter in the light of her increased extensor tone.

Mesi was seen by the paediatric neurologist for the first time at 6 weeks of CA. She performed the Hammersmith Neonatal Neurological Examination (HNNE). It revealed that Mesi had poor asymmetric visual orientation and that her spontaneous movements showed little variation and were jerky. She also had axial hypotonia and asymmetry in limb tone between left and right.

At 3 months of CA, Mesi had improved in her social eye contact and her extensor tone had decreased. Her Hammersmith Infant Neurological Examination (HINE) showed a global score of 33/78 indicating a high risk of CP. However, it was obvious that her extreme BPD affected her performance and, accordingly, the HINE scores attained. The General Movement Assessment revealed movements with little variation and no fidgety movements. In line with guidelines of the University Hospital of Helsinki, Mesi was recommended a weekly physiotherapy session at home with at least one of the parents present during the session. Physiotherapy was paid for by the hospital. As a part of regional practice, parents were given instructions on how to perform individualized exercise and stimulation with Mesi between therapy sessions. At 5 months of CA, Mesi obtained the official diagnosis of CP (ICD-10 G80.9). Her right limbs were clearly spastic, but also the tone in her left leg was atypical; it showed varying muscle tone. The trunk was very hypotonic; posture control and goal directed movements were impaired. In addition to physiotherapy sessions, now provided twice a week at home, she received adaptive seating to enhance eye–hand coordination and feeding.

At 8 months CA, Mesi had learnt to turn around and at 12 months CA she had reached the developmental stages of crawling, stable sitting, and standing with support. The X-ray of the hips indicated typical development. She was walking independently at 15 months CA.

At 3 years, an asymmetry in walking is seen, mainly manifested by a less active dorsiflexion of the right ankle. During ‘running’ the unilateral problem becomes more evident; it is more challenging to maintain balance and stereotyped posturing and tone in the right limbs increases. Her diagnosis is set as a spastic hemiplegia (G80.2) and her GMFCS level is II. She is keen on practising and participating in age-appropriate physical activities (e.g. riding a push-bike is one of her present favourites). She uses her left hand age-appropriately, but she manages many daily tasks, like eating independently, also with the right hand or bimanually. Her communication skills are in the typical range for her age. At 2 years she started in day care (inclusive policy) and the physiotherapy, which is paid by the National Social Insurance Institution, continues once a week either in the day care or at home. At present, the most difficult problems are the presence of sensory over-reactivity in the right upper limb and fatigue in busy social situations. The clinical follow-up continues in the multidisciplinary paediatric rehabilitation unit in the children’s hospital.

Mesi’s parents are overtly happy with their active, persistent, and cheerful daughter. Mesi’s development has been much more favourable than anyone had expected. It is impossible to know which factors contributed most to her outcome. However, we know for sure that her parents took care that Mesi practised every day and that her parents have a remarkable sensitivity, which they used to let Mesi discover her own activities and her own world. This, most likely, has already made her an actor in her own life.

CEREBRAL PALSY

Definition

CP is defined as a group of disorders of the development of movement and posture, causing activity limitation, that are attributed to non-progressive disturbances that occurred in the developing foetal or infant brain (Rosenbaum et al. 2007). In addition, CP is often accompanied by comorbidities like disturbances of sensation, hearing and visual deficits, communication and learning problems, intellectual disability, epilepsy, and behavioural and skeletal problems. The description of CP highlights its true clinical challenge: its large heterogeneity in phenotype. In addition to the fact that every child is a unique individual, every child with CP is different.

To date, various risk factors – in isolation or in additive or interactive combination – have been reported for CP (see Chapter 3). Nonetheless, the mechanisms leading to CP are currently not well understood. The clinical impression is that the aetiology of CP acts more as a vicious circle of multifactorial negative incidents than as a single incident.

Classification

The classical way to describe CP is based on its topographic features (i.e. the parts of the body involved in CP). Accordingly, hemiplegia refers to functional impairment dominating in one side of body and diplegia refers to the predominance of functional limitation in both legs. When all four limbs are affected equally, the condition is called either quadriplegia or tetraplegia. In clinical practice, topographical description is challenging since there is no definite objective measure to define, for instance, at what point diplegia changes into quadriplegia. The Surveillance of Cerebral Palsy in Europe (SCPE) has provided an alternative way to classify CP: it classifies CP into unilateral (one side of body) or bilateral (both sides of body) CP. According to the Australian Cerebral Palsy Register Report, unilateral CP covers 38% of all children with CP, whereas bilateral CP, including diplegia and quadriplegia, covers 37% and 24%, respectively (ACPR Group 2013).

In addition to the topographic definition of CP, the predominant features of the motor impairment are classified. The SCPE expert group has recommended using the following CP sub-types: spastic CP, dyskinetic CP (including both dystonic and choreo-athetotic types), ataxic CP, and non-classifiable CP (Cans 2000). The majority of children with CP have the predominantly spastic types (86%; ACPR Group 2013). In the dyskinetic and ataxic sub-types, signs of spasticity may also be present. If there is a combination of clinical findings of both spasticity and dyskinesia or ataxia, SCPE recommends classifying the type of CP according to the dominant clinical feature. In young children (i.e. children younger than 2 years of age), it may be difficult to define the type of CP. Therefore, best practice is to communicate this difficulty with the family and leave the type first as ‘non-classified’ until the type becomes clear with increasing age. The definitions of different subtypes (Table 2.1) and the hierarchical classification tree of CP subtypes shown in Figure 2.1 are good clinical guides (Cans 2000). The advantage of using the SCPE classification is that it allows for harmonization of diagnostic criteria both at local and national level. Such harmonization is the base for benchmarking the quality of diagnostic processes, national or international CP registers, and intervention trials.

In clinical practice, the use of classifications is hampered by two problems. The first problem is that the phenotype of CP evolves over time due to physical growth, overall development, and interventions. The changing phenotype interferes with the classification of the sub-types of CP. The second problem is that the topographic classification of CP, not the SCPE classification, form the defining criteria in the International Classification of Diseases (WHO ICD-10). It is this ICD-10 classification that many hospitals are obliged to use as a source for codes of diagnosis in official patient records, therewith hampering the widespread use of the SCPE classification.

Figure 2.1 Decision tree for the classification of the various types of cerebral palsy (based on Cans 2000).

The type of CP is not equal to the functional performance of a child with CP even though this is often used as an approximate of the child’s performance. In addition to disclosing the type of CP, it is also important to tell parents that the majority of children with CP will walk either independently or with aids. The communication on the child’s gross motor potentials is facilitated by the use of two tools: the Gross Motor Function Measure (GMFM) and the Gross Motor Function Classification System (GMFCS). The GMFM is used to evaluate change in the gross motor function over time in children with CP (available at www.canchild.ca). The GMFCS addresses the severity of mobility limitations (Palisano et al. 1997). It describes performance of children with CP in five distinct levels. The evolution of gross motor function by age has been integrated into the classification criteria by age bands (criteria before 2nd birthday, between 2nd and 4th birthday, between 4th and 6th birthday, between 6th and 12th birthday and between 12th and 18th birthday) (available at www.canchild.ca). In children older than 2 years, the GMFCS has shown to be relatively stable over time. Yet, in children younger than 2 years who have been classified according to the GMFCS, about 40% of the children change classification level when they grow older, with the majority moving to a less functional level (Gorter et al. 2009).

The GMFCS has been the foundation model for other functional classification systems, of which the most widely used are the Manual Ability Classification System (MACS), the Communication Function Classification System (CFCS), the Eating and Drinking Ability Classification System (EDACS), and Visual Function Classification System (VFCS) (see Chapter 8).

EARLY IDENTIFICATION OF CEREBRAL PALSY

Early Clinical Signs of CP

In the neonatal period and in early infancy, the clinical signs of developmental motor disorders are often very unspecific. In addition, the behavioural state and the somatic stability of the infant should be taken into account when performing a neonatal or infant neurological examination, especially during the first year of life. If the infant is unstable, hungry, in pain, or crying constantly, reliability of neurological findings is questionable and findings should be interpreted with caution.

Early clinical signs of CP are not specific to CP; instead, they are general signs