Cerebral palsy

Definition

Cerebral palsy is a term which covers a group of non-progressive, non-contagious neurological disease which cause physical disability.

Epidemiology

In the industrialised world, the incidence of cerebral palsy is about 2/1000 live births with a male:female ratio of about 1.3:1.

Pathophysiology

The pathophysiology of this condition is uncertain and generally no specific cause is found. However there are certain risk factors which increase the chance of the child developing this condition.

Risk Factors

• Prematurity (almost all cerebral palsy babies are premature)
• Congential infections
• Birth trauma
• Hypoxia
• Chemicals (alcohol, smoking etc.)

Clinical Features

There are four different types of cerebral palsy which is important because they have different symptoms. Spastic is the most common (70%) form. Ataxic, athetoid/dyskinetic and mixed which is unsurprisingly a mixture. These account for 10% each of the remainder of cerebral palsy sufferers.

Spastic

The main symptom of spastic cerebral palsy is spasticity (muscle overactivity resulting in resistance to stretching), which probably isn't very surprising given the name of the condition. This is further split into hemiplegic, quadraplegic and diplegic spastic cerebral palsy based on which part of the body it affects.

• Hemiplegic- arm and leg on same side
• Diplegic - both legs but arms far less
• Quadraplegic - whole body

Ataxic

This generally affects balance, causes hand tremors which affects reading and writing and can cause speech problems. Hypotonia (rather than spasticity) may also be present.

Athetoid

This is characterised by involuntary movements and a progression from hypotonia to hypertonia. Due to these differences in muscle tone and the involuntary movements, staying in steady positions such as standing upright or sitting still can be difficult.

Associated problems

These don't happen in every case of cerebral palsy but there is a higher likelihood

• Mental retardation (IQ<50) occurs in 30-50% but it should be mentioned that cerebral palsy patients generally do not have problems with their intelligence. It associated with spastic quadraplegia
• Seizures and epilepsy occurs in 21%
• Blindness occurs in 11%
• Medical complications are common: GI problems, aspiration pneumonia, dental problems.

Investigations

The problem with cerebral palsy, is because nobody really knows what causes it, a lot of these investigations are trying to rule out some pretty rare stuff. So don't worry too much - it's enough to know about the symptoms and classifications really. Still, I've already done this stuff so you may as well have a cursory glance at it.

Bloods

• TFTs - don't know why yet but it says so at Patient.co.uk
• Lactate and pyruvate levels - exclude some mitochondrial cytopathies (v. rare)
• Organic and Amino acid levels - exclude conditions caused by abnormalities in this area
• Chromosome analysis - exclude genetic conditions

Other fluids

• Lumbar puncture - abnormal protein, lactate and pyruvate may be evidence of neonatal asphyxia

Imaging

• Ultrasound (in preterm babies) - identifies risk of cerebral palsy
• CT - to detect structural malformations and vascular abnormalities
• MRI - white matter lesions, asphyxia

Management

This is a chronic disability and as such we bring in that old chestnut the multidisciplinary team. For cerebral palsy, this would consist of something like:

• Physiotherapist
• Occupational therapist
• Speech therapist
• Specialist nurses (probably?)
• GP
• Paediatrician

Basically, a wide variety of people.

Medical treatment

Muscle relaxants are used to treat the spasticity, baclofen being first-line and dantrolene being used in severe cases. Diazepam can also be used if the others don't work.

There are also a variety of injections which can be given to relieve muscle spasticity (such as botulinum or phenol).

Surgery

There are a variety of surgical procedures. You don't need to know them in detail but it can help with some of problems that arise (such as scoliosis).

Other interventions

Mobility aids are very important - mobility is one of the biggest issues in cerebral palsy and this is where the occupational therapist is at the most useful. Finally, care for the carers is also important. In any chronic disabling condition, the people looking after the patient are at a higher risk of developing psychological but also physical health problem.

Prognosis

This is incredibly variable. Mild forms of the disease will mean that the patient probably has a normal life expectancy but at its most severe, the chances of reaching the age of 20 drop to 40%. Severity would include severe quadriplegia, epilepsy, mental retardation and medical complications (gasto-oesophageal reflux or pneumonias).