Introduction

Epilepsy is a neurological disorder characterised by recurring, unprovoked seizures caused by abnormal electrical activity in the brain. It is diagnosed when a person experiences at least two unprovoked seizures more than 24 hours apart, has a single seizure with a high risk of recurrence, or is diagnosed with an epilepsy syndrome.¹ 

Cerebral palsy (CP) is a group of permanent conditions that affect movement, muscle tone or posture. It is caused by non-progressive damage or abnormalities in the developing brain before, during or shortly after birth.² The brain damage or malformations are non-progressive, which means they do not get worse over time, but the effects on the body can change as the child grows.³ 

Understanding the link between epilepsy and cerebral palsy is of paramount importance. These two conditions often co-occur, with a staggering 30-50% of children with cerebral palsy also diagnosed with epilepsy. This significant overlap stems from the fact that both conditions can arise from similar brain injuries or abnormalities, such as birth complications, lack of oxygen, stroke, infections, or head trauma.⁴  

The presence of epilepsy in children with cerebral palsy is frequently associated with more severe intellectual disabilities, movement disorders, behavioural problems, and lower quality of life. The brain damage disrupting motor function in cerebral palsy also increases susceptibility to abnormal electrical activity, leading to seizures. More severe cerebral palsy types involving extensive brain damage have a higher risk of comorbid epilepsy.⁵ 

Effective management requires a multidisciplinary approach, addressing not only the motor impairments of cerebral palsy but also the seizure control and potential side effects of antiepileptic medications. Moreover, children with both conditions may require more intensive monitoring and follow-up, as the presence of seizures can indicate a more severe brain injury and potentially impact the prognosis and long-term outcomes. Acknowledging this strong link can drive further research into the underlying mechanisms, risk factors, and potential preventive measures, ultimately leading to improved outcomes for affected individuals.^6,7

Causes and risk factors

Causes of epilepsy 

Genetic Factors: Hereditary components and genetic changes that increase seizure susceptibility.

Brain Injuries: Head trauma, strokes, lack of oxygen to the brain, and brain tumours.

Structural Abnormalities: Malformations present at birth or abnormal blood vessel formations.

Pre-existing Conditions: Cerebral palsy, developmental disabilities, and autism spectrum disorder (ASD).

Other Medical Conditions: Brain infections (e.g., meningitis, encephalitis), prenatal injuries, metabolic disorders, and neurodevelopmental conditions.⁸

Causes of cerebral palsy  

Prenatal Factors: Maternal infections (e.g., cytomegalovirus, rubella), birth defects, placental abnormalities, reduced oxygen to the brain, premature birth, and traumatic delivery. 

Postnatal Factors: Head injuries, brain infections, strokes, severe jaundice, or low blood sugar levels in infancy.⁹

Types and classifications 

Types of epilepsy¹⁰

Generalised epilepsy 

• Affects both sides of the brain or widespread brain networks at once
• Includes tonic-clonic, absence, myoclonic, and atonic seizures

Focal seizures 

• Focal onset aware seizure: A focal aware seizure occurs when a person is conscious and awake during the seizure. This was formerly referred to as a simple partial seizure
• Focal onset impaired awareness: A focal impaired awareness seizure is characterised by confusion or some other impairment in awareness during the seizure. This was formerly referred to as a complicated partial seizure. This was called a complicated partial seizure in the past

Unknown onset seizures 

• Seizure onset is not known or not witnessed
• Unknown onset seizures may occur when the seizure happens at night while the person is asleep or if the person lives alone and the seizure is not witnessed by anyone
• It may later be reclassified as focal or generalised seizures once more information is available

The classification helps guide further testing and determine the appropriate treatment approach, as treatments may differ depending on the type of seizures.

Types of cerebral seizures

1. Spastic cerebral palsy 

Spastic cerebral palsy is the most common form, accounting for 77% of cases. Also known as hypertonic CP and involves high muscle tone and exaggerated, jerky movements (spasticity) due to damage to the brain's motor cortex or pyramidal tracts that control voluntary movement. 

The motor cortex is found on both sides of the brain, with pyramidal tracts connecting each side to the opposite side of the body. Damage to the right motor cortex causes problems with left-sided movement and vice versa.¹¹

Common symptoms include: 

• Awkward reflexes 
• Muscle tightness or contractures 
• Difficulty crawling/walking 
• Stiff muscles in one or more body parts

2. Athetoid (dyskinetic) cerebral palsy 

About 2.6% of children with CP are diagnosed with athetoid or dyskinetic cerebral palsy. This non-spastic type causes involuntary movements in the face, trunk, and limbs due to fluctuating muscle tone hypotonia (loosened muscles) and hypertonia (stiffened muscles).

It damages the brain's basal ganglia, which regulates voluntary movement and eye movements, and/or the cerebellum, which controls balance and coordination.

Extrapyramidal involves disruption to the brain tracts regulating involuntary reflexes signalled by these areas. Common symptoms include: 

• Feeding difficulties 
• Floppy limbs 
• Poor posture 
• A stiff or rigid body 

Despite being less common, athetoid/dyskinetic CP can significantly impact motor function and require specialised care.

3. Hypnotic cerebral palsy

Hypotonic or atonic cerebral palsy accounts for about 2.6% of cases. It is characterised by low muscle tone, which causes a lack of strength and firmness, resulting in floppy muscles. This muscle floppiness and instability can delay developmental milestones like crawling, standing, and walking. 

Common symptoms include: 

• Flexible joints/ligaments 
• Poor head control 
• Loose muscles 
• Impaired balance and stability 

Despite being less prevalent, hypotonic CP's low muscle tone and associated motor delays require early intervention and therapies to improve muscle strength and function.

Ataxic cerebral palsy

Ataxic cerebral palsy, accounting for 2.4% of cases, impairs balance, coordination, and voluntary movement control due to damage to the cerebellum, the brain region responsible for coordinating physical movements.

Individuals with this type of CP experience: 

• Tremors 
• Reduced muscle tone 
• Poor coordination and depth perception 
• Shakiness 
• Speech difficulties 
• A wide-legged gait when walking¹¹

While less common than spastic forms, the movement and balance issues caused by cerebellar damage in ataxic CP require physical, occupational, and speech therapies to improve functional abilities. 

Mixed cerebral palsy

In some cases, the brain damage causing cerebral palsy affects multiple areas. This results in mixed-type cerebral palsy, where a child exhibits symptoms of more than one CP type, such as a combination of spastic and dyskinetic movement disorders.

Symptoms and diagnosis  

Epilepsy symptoms 

• Repeated seizures - sudden bursts of abnormal electrical brain activity
• Seizure types include:
  • Staring spells 
  • Muscle jerking 
  • Convulsions 
  • Loss of awareness/consciousness
• Warning signs (aura) like dizziness, fear, and visual disturbances may occur before the seizure¹²

Epilepsy diagnosis 

• Based on the description of seizure symptoms and medical history
• Electroencephalogram (EEG) to detect abnormal brain wave patterns
• Brain imaging tests like MRI to identify potential causes¹²

Cerebral palsy symptoms

• Movement disorders - stiff muscles, uncontrolled movements, poor coordination/balance
• Developmental delays - delayed milestones like sitting, crawling, walking
• Speech/eating difficulties - delayed speech, swallowing problems
• Other issues - vision, hearing, intellectual disabilities, seizures¹³

Cerebral palsy diagnosis 

• Based on monitoring development and motor skill progression
• Brain imaging (MRI, ultrasound) to detect brain abnormalities
• Testing for associated conditions - vision, hearing, cognitive function
• Determining primary movement disorder type (spastic, dyskinetic, ataxic, etc.)¹³

Treatment

Treatment of epilepsy 

Medications are the primary treatment for controlling seizures in epilepsy. Over 20 anti-seizure medications (ASMs) are available, with the choice depending on factors like seizure type, age, and potential side effects. The goal is to stop seizures using the lowest effective dose of medication while minimising side effects.¹⁴ 

When medications are ineffective, other treatment options may be explored, such as the ketogenic (high-fat, low-carb) diet, which can help reduce seizures.¹⁵ Devices like vagus nerve stimulators, implanted to send electrical impulses, can also prevent seizures. 

For drug-resistant epilepsy, epilepsy surgery to remove the seizure foci or implant neurostimulation devices may be considered. Newer options like responsive neurostimulation and laser therapy are also being explored. 

Proper medication management, identifying and avoiding seizure triggers, and regular follow-ups are crucial for optimal seizure control.¹⁴  

Management of epilepsy 

• Take medications as prescribed, get adequate sleep, identify triggers 
• Regular follow-ups to monitor seizure control and medication levels 
• Referral to epilepsy centres for drug-resistant epilepsy to explore other options¹⁵

Treatment of cerebral palsy¹⁶

The treatment and management of cerebral palsy involves a multifaceted approach: 

• Oral medications like baclofen and diazepam can help relax stiff or spastic muscles 
• Physical, occupational, and speech therapies improve mobility, flexibility, and strength and address difficulties with swallowing or communication
• Botulinum toxin injections into overactive muscles can also reduce spasticity 
• In some cases, surgical interventions may be recommended, such as:
  • Orthopaedic surgery to correct deformities or release tight muscles 
  • Selective dorsal rhizotomy reduces spasticity by cutting specific nerve rootlets which gives rise to spasticity 
  • Implanting a baclofen pump 

Management of cerebral palsy

Other interventions include braces, splints, orthotics, wheelchairs, and walking aids to improve function and independence. Additionally, managing co-existing conditions like seizures, vision, or hearing problems is essential for comprehensive care. A tailored, multidisciplinary approach is key to maximising the individual's abilities and quality of life.

Summary 

Epilepsy and cerebral palsy are two neurological conditions that often co-occur, with 30-50% of children with cerebral palsy also diagnosed with epilepsy. Both disorders can arise from similar brain injuries or abnormalities, such as birth complications, lack of oxygen, stroke, infections, or head trauma. Epilepsy is characterised by recurrent seizures caused by abnormal electrical activity in the brain, while cerebral palsy is a group of permanent conditions affecting movement, muscle tone, and posture due to non-progressive brain damage. The presence of epilepsy in children with cerebral palsy is associated with more severe intellectual disabilities, movement disorders, behavioural problems, and lower quality of life. Effective management requires a multidisciplinary approach, addressing seizure control with medications or other treatments, as well as the motor impairments and associated conditions of cerebral palsy, through therapies, medications, and surgical interventions when necessary.