Cerebral Palsy

Introduction

Cerebral palsy, also known as CP, is a non-progressive, permanent neurological condition commonly affecting normal movement and posture.¹

It is the most prevalent cause of childhood motor impairment, with the UK incidence rate at around 1 in 400 births.¹

The severity and type of symptoms vary significantly between individuals, meaning CP has a wide range of presentations.

Aetiology

Cerebral palsy is caused by damage to the developing brain which can occur while the baby is in utero, during birth or in the neonatal period. Often, this is caused by hypoxia, haemorrhage or infection.

Different areas of the brain being damaged correspond to different clinical features of cerebral palsy. 

Risk factors

The aetiology of CP is multifactorial, often relating to the prenatal period and mechanisms of neonatal brain hypoxia.² Significant risk factors are listed below.

Antenatal risk factors include:³

• Multiple gestation
• Chorioamnionitis
• Maternal TORCH infections (toxoplasmosis, rubella, CMV, and herpes simplex)

Perinatal risk factors include:³

• Prematurity (significant risk factor)
• Low birth weight
• Birth asphyxia
• Neonatal sepsis

Postnatal risk factors include:³

• Meningitis
• Severe hyperbilirubinaemia (neonatal jaundice)

Other risk factors include:^3,4

• Any risk factors for prematurity are indirect risk factors
• Low socioeconomic status
• CP is more common in boys than girls at around 1:1.3

Clinical features

Cerebral palsy often presents with delayed motor milestones:²

• Not sitting by 8 months
• Not walking by 18 months
• Hand preference before 12 months

Importantly, these milestones must be corrected for gestational age (prematurity is a significant risk factor for cerebral palsy). 

For more information, see the Geeky Medics guide to developmental milestones.

Other clinical features of cerebral palsy may include:²

• Tone abnormalities (floppiness or stiffness)
• Abnormal movements (e.g. asymmetrical movements, fidgety movements, lack of movement)
• Feeding problems such as choking or dysphagia
• Persistent toe walking

As CP is a non-progressive condition there should be no regression in milestones. This is a red flag in any child and would suggest an alternative diagnosis.

Types of cerebral palsy

The clinical features of cerebral palsy depend on the area of the brain affected. Cerebral palsy can be classified based on which clinical features predominate in an individual. It is common for there to be a mixed picture of symptoms spanning different subtypes if there have been multiple areas of insult to the brain.

Spastic cerebral palsy

Spastic cerebral palsy is characterised by velocity-dependent hypertonia (spasticity) and hyperreflexia. It is the most common type of CP.⁵ In this type of CP, when a limb is moved quickly the muscle can suddenly increase in tone and stop further movement (a spastic catch).

Dyskinetic cerebral palsy

Dyskinetic cerebral palsy is characterised by involuntary, uncontrolled, recurring movements, fluctuating muscle tone and persistent primitive reflexes.⁵

Dyskinetic CP is divided into two subtypes:

• Dystonic CP: abnormal posturing and hypertonia
• Choreoathetotic CP: chorea and athetosis

Ataxic cerebral palsy

Ataxic cerebral palsy is characterised by loss of muscular coordination resulting in ataxia and tremor. It is the least common type of cerebral palsy, and this group of patients is likely to contain other progressive genetic conditions which cause ataxia. A patient with ataxic CP may point past your finger during a finger-to-nose coordination test (‘past pointing’).⁵

Classification by limb involvement

Cerebral palsy can also be classified by which part of the body is most affected:⁶

• Monoplegic cerebral palsy affects one limb
• Hemiplegic cerebral palsy affects one side of the body
• Diplegic cerebral palsy is symmetrical, with the lower limbs more affected than the upper limbs
• Quadriplegic cerebral palsy indicated all four limbs are severely affected.

However, this classification system is becoming less commonly used as it is better to describe the limbs involved and use functional grading systems such as the Gross Motor Function Classification System (GMFCS) for lower limb function and The Bimanual Fine Motor Function (BFMF) for upper limb function.⁵ 

Investigations

Cerebral palsy is a clinical diagnosis, and there are no definitive diagnostic tests.³

An MRI brain may be requested for a child presenting with possible CP.³ This may show damage in white matter, deep grey matter and the basal ganglia.⁷

Neuroimaging will not usually change management unless an alternative cause of symptoms is found. It can be useful in excluding other differential diagnoses (e.g. multiple sclerosis).

Management

The management of cerebral palsy will vary depending on the type and severity of the condition, as well as managing any complications that arise. A multidisciplinary approach is crucial in managing the many different aspects of this complex condition.

Conservative management

Conservative management of cerebral palsy includes:

• Physiotherapy: important in helping to assess and improve function and mobility, as well as preventing muscle contractures and pain.
• Occupational therapy: enables patients to perform everyday activities and modify homes to be more accessible.
• Speech and language therapy: can help patients with communication and swallowing difficulties.
• Dietician input: address feeding problems and assess nutritional status. Some patients with dysphagia may require PEG feeding.

Medical management

Medical management of cerebral palsy is aimed at managing symptoms and may include:^7,8

• Hyoscine hydrobromide or glycopyrronium bromide: excess drooling
• Diazepam: pain
• Baclofen: hypertonia
• Botulinum toxin type A injections: used if spasticity is severely affecting function or causing significant pain

Surgical management

Hip displacement is very common in people with cerebral palsy. Surgical intervention may be required in some cases.⁸

Complications

Although cerebral palsy is a non-progressive disease, complications can become apparent as a child grows up. Complications may include:²

• Problems with feeding and aspiration
• Drooling
• Constipation
• Visual and hearing impairment
• Epilepsy
• Learning disability
• Speech difficulty
• Osteopenia and osteoporosis (especially if non-mobile)
• Sleep disturbance

Key points

• Cerebral palsy is a non-progressive, permanent neurological condition affecting normal movement and posture caused by damage to the developing brain. 
• Delayed motor milestones or problems with tone are common presenting features
• Cerebral palsy is a clinical diagnosis although neuroimaging (MRI brain) is useful to exclude other differential diagnoses
• Management of cerebral palsy involves managing symptoms and addressing complications using a multidisciplinary approach
• Cerebral palsy is non-progressive but complications may occur including problems with feeding, drooling, constipation, epilepsy and osteopenia/osteoporosis. 

Reviewer

Consultant Paediatric Neurologist

Editor

Dr Chris Jefferies

References

1. SCOPE. Cerebral palsy (CP). Published in 2022. Available from: [LINK]
2. NICE CKS. Cerebral palsy. Published in 2019. Available from: [LINK]
3. BMJ Best Practice. Cerebral palsy. Available from: [LINK]
4. J L Hutton, K Hemming and UKCP collaboration. Life expectancy of children with cerebral palsy. Published in 2006. Available from: [LINK]
5. European Commission. CP and CP subtypes. Available from: [LINK]
6. Trishla Foundation. Cerebral Palsy Types – Spastic, Dyskinetic, Ataxic, Mixed Cerebral Palsy. Published in 2017. Available from: [LINK]
7. NICE. Cerebral palsy in under 25s: assessment and management. Published in 2017. Available from: [LINK]
8. NICE. Spasticity in under 19s: management. Published in 2012. Available from: [LINK]