Cerebral palsy

Causes

There can be many causes for the brain damage that leads to CP, but for most babies that develop the condition, doctors are not able to identify a particular cause.

Types

The kind of symptoms someone with CP experiences depends on which part of the brain is damaged.

Cerebral palsy can cause damage in different parts of the brain, which results in diverse symptoms. 

There are four main types of CP:

Spastic CP

This is by far the most common form of CP and is caused by damage to the motor cortex, the main area at the top of the brain that is responsible for controlling body movements.

For body movements to occur smoothly, different muscle groups have to work together in the correct sequence, with some contracting while others relax. In spastic CP, muscles tend to be stiff and tight and the muscle groups do not receive messages from the brain in the correct sequence, making it difficult to move smoothly.

People with spastic CP tend to:

• Make stiff, jerky movements, and;
• Have tight, flexed joints.

Dyskinetic CP

Dyskinetic CP is much less common. It occurs because of damage to an area of the brain called the basal ganglia, which regulates messages between the motor cortex and the spinal cord, helping to control voluntary movements.

People with dyskinetic CP can have three kinds of movement disorders:

• Dystonia - a person makes slow, twisting, repetitive movements or takes on abnormal postures. This is caused by involuntary muscle contractions that occur during a planned movement;
• Athetosis - a person has fluctuations in muscle tone, from loose and floppy to stiff and tight. It tends to create slow, involuntary writhing movements. People with athetosis can have trouble controlling their facial, mouth and tongue muscles and may have difficulty controlling actions, such as speaking, eating, drinking and managing saliva, and;
• Chorea - a person has involuntary movements that are abrupt and unpredictable. These can cause problems with movement, swallowing and speech.

Ataxic CP

Ataxic CP is the least common form of CP. It occurs as a result of damage to the cerebellum, an area at the base of the brain that helps to control balance.

People with ataxic CP tend to have difficulties maintaining their balance. They may also make shaky or tremor-like movements and have trouble with speech and swallowing, in addition to controlling eye movements.

Mixed or combined CP

With combined or mixed CP, a person is affected by more than one of the CP types described above.

Signs and symptoms

Cerebral palsy affects each person differently. Symptoms can range from mild to severe and may affect many different parts of the body.

While the damage that causes CP generally happens before or shortly after birth, it may take quite some time for symptoms to become apparent.

Infants and young children

Signs of cerebral palsy can include:

• Floppiness or low muscle tone;
• Stiffness or muscle spasms;
• Difficulty controlling muscles and posture;
• Poor reflexes;
• Problems with feeding and swallowing, and;
• Preferring to use one side of the body.

CP can affect development, which means that infants and small children with the condition may not be able to perform actions expected for children of their age. These developmental milestones can include actions such as sitting up, rolling over, crawling, walking and word use. There is a wide range of 'normal' times for achieving these milestones and being 'late' in one alone does not necessarily mean there is cause for concern over the child's development. You should speak to your doctor if you have concerns about your baby's developmental milestones. Routine check-ups with maternal child health nurses are also effective in identifying developmental concerns.

Other medical conditions can also cause similar symptoms and your child may be referred to a paediatrician for further assessment.

Related conditions and problems

Because of the damage to the brain and problems with movement, people with cerebral palsy may have a range of health conditions and problems.

These can include:

• Difficulties with mobility. People with CP may be unable to walk, or require assistance from a range of different aids;
• Pain. This can be caused by tightly contracted muscles, and bone and joint problems from the abnormal postures and movements that place strain on the body;
• Epilepsy, which causes seizures;
• Difficulty eating and drinking, due to problems chewing and swallowing;
• Difficulty communicating because of problems controlling mouth and tongue muscles or breathing;
• Problems controlling saliva, leading to drooling;
• Hearing loss;
• Vision problems and blindness;
• Sleeping difficulties that can be due to pain, muscle spasms, epilepsy, or an inability to change position in bed;
• Abnormalities of the bones, particularly an abnormally curved spine ( scoliosis) and hip displacement or dislocation;
• Difficulties controlling the bladder, leading to urinary incontinence;
• Problems with the digestive system, including heartburn and constipation;
• Emotional and behavioural problems, and;
• Intellectual disability and learning difficulties.

Cerebral palsy can cause difficulty with mobility. 

Intellectual disability

Around half of people with cerebral palsy have an intellectual disability and roughly one in five has a moderate or severe intellectual impairment.

While it is true that the more physically impaired a person is, the more likely they are to have an intellectual disability, it is important not to assume that this is always the case. Some people with CP may have severe physical disability, but no intellectual impairment, while others may have mild physical symptoms along with an intellectual disability.

Methods for diagnosis

The diagnosis of cerebral palsy is often not straightforward. Other health conditions can cause similar symptoms to CP and need to be ruled out. It can take repeated visits and tests to diagnose CP.

Even when a diagnosis is made, it may take months or even years of reviewing the child's development to fully understand the types of symptoms, their severity and the affected parts of the body.

Tests

In an initial assessment, the child's movements will be assessed for signs that they have cerebral palsy. Further tests may be recommended in order to rule out other health conditions and assess brain and muscle function.

Tests can include:

• Magnetic resonance imaging (MRI);
• Ultrasound;
• Computerised tomography (CT) scan;
• Electroencephalogram, which measures electrical activity in the brain and can detect epilepsy, and;
• Electromyogram, which measures the function of muscles and the peripheral nervous system.

Severity of CP

Since cerebral palsy causes a wide range of symptoms and affects each person differently, as well as identifying the type of CP someone has, doctors may assess the symptoms according to:

• Which parts of the body are affected. For example, quadriplegia can be used to describe CP that affects all four limbs, while hemiplegia refers to both limbs on one side of the body, and;
• How severely symptoms affect different aspects of a person's function, such as gross motor skills (the ability to walk or run), fine motor skills (ability to handle objects) and communication.

Types of treatment

People with cerebral palsy will generally have a team of healthcare professionals helping to provide ongoing care tailored for their needs. The types of treatment they may require depends on:

• The nature of their symptoms;
• The severity of the symptoms and affected body parts, and;
• Complications or health consequences of living with CP.

Medications

Medication can help improve symptoms that make movement difficult for people with cerebral palsy. Medications commonly prescribed include:

• Diazepam - a long-acting muscle-relaxant that can be taken orally to provide quick relief for muscle spasms and pain;
• Baclofen - a muscle-relaxant suitable for longer-term use. This medication can be delivered by a surgically implanted pump if necessary, and;
• Botulinum toxin type A - this can be injected into muscles affected by spasticity to reduce stiffness. The effect lasts around 3-6 months and injections can be repeated as necessary.

Other medications may also be recommended to treat conditions such as epilepsy, heartburn, sleeping problems and pain.

Surgery

Various kinds of surgery may be recommended to help treat a range of issues with cerebral palsy.

Surgeries include:

• Orthopaedic surgery to help correct problems with joints and bones, by lengthening muscles and tendons that have contracted too much;
• Surgical implantation of a feeding tube in cases where problems with swallowing or eating skills mean that feeding by mouth is not recommended, and;
• Selective dorsal rhizotomy. In this procedure the surgeon cuts some of the nerves in the lower spinal cord to help relieve stiffness in the legs. It is usually only recommended for people with CP who have severe symptoms that have not responded well to other treatments.

Surgery may also be recommended to treat conditions, such as scoliosis, urinary incontinence, vision and eye movement disorders, salivary problems and heartburn.

Physiotherapy and occupational therapy

Physiotherapists and occupational therapists can help people with cerebral palsy to improve their movement and learn more effective ways to perform daily activities.

They may use a variety of approaches including:

• Exercises to strengthen muscles and improve balance and movement;
• Providing supportive casts and orthotics to help stretch muscles and improve posture, and;
• Providing a variety of aids and specialised equipment to help with movement and daily activities.

Therapists assist people with cerebral palsy in managing their daily activities. 

Speech pathology

Speech pathologists can help people with cerebral palsy improve their communication skills. This may include exercises to help improve speech or, if speech is very impaired, learn to use other methods to communicate, such as signing or using assistive technology (such as communication boards or speech-generating devices).

Speech pathology can also assist with swallowing, eating and drinking difficulties.

Psychology, counselling and support

Psychologists can provide help for people with cerebral palsy in a number of ways. They can assess and provide guidance on a range of issues such as learning and development, dealing with chronic pain, improving sleep and emotional and behavioural issues. People with CP may suffer from depression and anxiety, and psychologists can also provide assistance, counselling and therapy for these conditions.

Social workers can provide home-based support for people with cerebral palsy and their families.

Vision care

Ophthalmologists and optometrists can provide treatments for vision problems associated with cerebral palsy, including short-sightedness and strabismus (also known as turned eye or squint).

Audiology

Audiologists can assess hearing loss and provide hearing aids.

Nutrition

People with cerebral palsy may need to take care with their nutrition for several reasons, including having difficulty swallowing, needing to control energy intake because they find it difficult to be physically active, constipation and heartburn.

Doctors and dietitians can help to provide tailored nutritional advice for meal planning.

Potential complications

As well as the health problems associated with cerebral palsy, a number of other complications may occur.

Medications

Managing medications for cerebral palsy can be complex, particularly if a number of medications are required to manage different symptoms and health problems.

Medications to relax muscles can have a range of side effects including drowsiness, confusion and lack of coordination. Rarely, the botulinum toxin can cause serious problems with breathing and swallowing.

Discussing medications, side effects and how to best manage them is part of treating CP. If you have any concerns, you can talk to your doctor or other health professionals.

Respiratory problems

People with CP who have problems with swallowing or heartburn can be at greater risk of developing respiratory problems, such as pneumonia and chronic lung disease.

Joint and bone problems

Living with CP can take a toll on the body. Muscle contracture (permanent shortening), bone abnormalities and abnormal postures can place extra strain on bones and joints. As a person with CP gets older, this can increase the risk of problems such as osteoarthritis and osteoporosis.

Depression

Living with CP can be challenging and adults with CP are at greater risk of developing depression. If you think you may be depressed, you can talk to your GP or a mental health professional. There are many treatments that can help overcoming depression.

Prognosis

Cerebral palsy causes lifelong disability and there is no cure. Treatments can help to reduce symptoms and improve independence and quality of life for people with CP.

Although the damage to the brain that causes CP does not get worse, over time symptoms can change and people with CP may experience some physical complications, as described above.

Prevention

Most cases of cerebral palsy cannot be prevented. Where there is a concern that women are at increased risk of delivering their babies very prematurely, doctors may recommend taking doses of magnesium sulphate, a compound that has been shown to reduce the risk of premature babies developing CP.

For newborn babies who have suffered a lack of oxygen before birth, treatments such as the use of a cooling cap, which reduce the temperature of the brain, may help to reduce the risk of brain damage.