Paralysis, causes,risk factors, treatment

Introduction

Paralysis is loss of the ability to move one or more muscles. It may be associated with loss of feeling and other bodily functions.

It is not usually caused by problems with the muscles themselves, but by problems with the nerves or spinal cord the brain uses to control muscles. A person with paralysis will usually have some form of nerve damage.

Classifying paralysis

Paralysis can be:

localised – where a specific section of the body is paralysed, such as the face or hand

Generalised – where a larger area of the body is affected

There are also a number of medical terms used to describe different types of paralysis. For example:

monoplegia – where one limb is paralysed

hemiplegia – where the arm and leg on one side of the body are paralysed

paraplegia – where both legs and sometimes the pelvis and some of the lower body are paralysed

tetraplegia – where both the arms and legs are paralysed (also known as quadriplegia)

Symptoms of paralysis 

Paralysis can be classified in a number of different ways. For example, it can be localised, affecting a particular part of the body, or generalised, affecting a wider area.

Examples of localised paralysis include:

facial paralysis – which is usually limited to one side of the face

paralysis of the handparalysis of the vocal cords – vocal cords are bands of tissue and muscle used to generate speech; paralysis usually only affects one vocal cord, which means the person is able to speak but their voice will be hoarse

Examples of generalised paralysis include:

monoplegia – where one limb is paralysed

hemiplegia – where the arm and leg on one side of the body are paralysed

paraplegia – where both legs are paralysed, or sometimes the pelvis and some of the lower body

tetraplegia (also known as quadriplegia) – here both the arms and legs are paralysed

Temporary and permanent paralysis

Paralysis can either be temporary or permanent.

Bell's palsy is a relatively common cause of temporary paralysis that causes temporary facial paralysis.

Sometimes paralysis that occurs after a stroke can also be temporary.

Paralysis caused by serious injury, such as a broken neck, is usually permanent.

Partial or complete paralysis

Paralysis can be:

partial – where there is some muscle function and sensation; for example, if a person can move one leg but not the other, or feel sensations such as cold and heat

complete – where there is complete loss of muscle function and sensation in affected limbs

Spastic or flaccid paralysis

Paralysis can be:

spastic – where muscles in affected limbs are unusually stiff or display spasms, and movements are not under the control of the individual (read about spastic paraplegia)

flaccid – where muscles in affected limbs are floppy and weak; muscles in flaccid paralysis may shrivel

People with spastic paralysis may experience muscle weakness with spasms (involuntary muscle contractions). People with flaccid paralysis often experience muscle weakness without spasms.

In some conditions, such as motor neurone disease or cerebral palsy, it is possible to experience episodes of spastic paralysis followed by flaccid paralysis, or the other way around.

Levels of spinal cord injury

When assessing the extent of a spinal cord injury, it is a case of determining where on the spine the injury occurred, and how badly related nerves and muscles have been affected.

The spinal cord is measured using a number and lettering system based on the vertebrae (disc-shaped bones that help support the spine and neck).

Your spine is made up of 24 vertebrae in total, consisting of:

seven cervical vertebrae in the neck – measured as C1 to C712

Thoracic vertebrae in your chest area – measured as T1 to T12

five lumbar vertebrae in your lower back – measured as L1 to L5

People with a spinal cord injury between C1 and C7 are likely to have paralysis in all four limbs (tetraplegia).

The extent of the paralysis and subsequent loss of muscle function will depend on how high up the injury occurred. For example:

someone with a C1 to C4 spinal cord injury will have little or no movement in their limbs and will probably only be able to move their head and possibly their shoulders – they will also need a ventilator to assist their breathingsomeone with a C7 spinal cord injury will be able to extend their elbows and may have some movement in their fingerssomeone with a T2 to T12 spinal cord injury will have fully functional muscles in the top half of their body, but little or no function in their lower limbs and will need a wheel chairsomeone with an L1 to L5 injury could have limited movement in their hips, knees and feet, but is likely to need a wheelchair or other type of mobility aid, such as a walking frame

What causes paralysis?

The three most common causes of paralysis are:

strokehead injury spinal cord injury – the spinal cord is made up of nerves that run through the spine and help control the body's musclesmultiple sclerosis

Sometimes paralysis can also occur as a result of a number of other conditions, such as cerebral palsy and Guillain-Barré syndrome. 

Living with paralysis

The type and extent of paralysis will determine the impact it has on a person's quality of life and day-to-day activities.

For example, a person who has lower limb paralysis (paraplegia) will usually be able to lead a relatively independent and active life, using a wheelchair to carry out their daily activities.

But a person with paralysis that affects both their arms and their legs (tetraplegia/quadriplegia) will need a great deal of support, and it is unlikely they will be able to live without a dedicated carer.

Paralysis can also cause a number of associated secondary conditions, such as urinary incontinence (an inability to control the flow of urine) and bowel incontinence (where stools leak from the back passage). It may also affect sexual function in both men and women.

There is currently no cure for paralysis, except in certain conditions. In cases of permanent paralysis, treatment aims to:

help a person live as independently as possibleaddress any associated complications that arise from paralysis, such as pressure ulcers (sores that develop when the affected area of tissue is placed under too much pressure)address bladder and bowel problems that are secondary to paralysistreat spasms and complications resulting from paralysis

Mobility aids such as wheelchairs and orthoses can help a person with paralysis.

Manual wheelchairs are designed for people with good upper body strength. Electric wheelchairs are designed for people with poor upper body muscle strength or paralysis in all four limbs

Treating paralysis 

There is currently no cure for permanent paralysis. The aim of treatment is to help a person adapt to life with paralysis by making them as independent as possible.

Another important goal of treatment is to address health problems and associated complications that arise from paralysis, such as pressure ulcers.

Various treatment options and aids available for people with paralysis are described below.

Mobility aids

A range of mobility aids, such as wheelchairs, are available for people with paralysis.

Wheelchairs

There are two main types of wheelchair:

manual wheelchairs – designed for people with good upper body muscle strengthelectric wheelchairs – designed for people with poor upper body muscle strength or quadriplegia (paralysis in all four limbs)

The NHS supplies wheelchairs free of charge, but the range of models available is often limited. If you want a more sophisticated model, you will have to pay some or all of the cost.

There is also a relatively new type of wheelchair known as a standing chair, which functions like a wheelchair but allows the person to rise to a standing position. This helps reduce their risk of developing pressure sores.

Orthoses

Orthoses are an alternative to wheelchairs. They are braces, usually made of plastic or metal, designed to improve the function of a limb and compensate for muscle weakness.

Examples of orthoses include:

wrist-hand orthoses – designed to transfer force from a functioning wrist to paralysed fingers

ankle-foot orthoses – designed for people with some lower limb function to help them move their feet while walking

knee-ankle-feet orthoses – designed for people with tetraplegia (paralysis in the lower limbs, also known as quadriplegia) to stabilise the knee and ankle and let them swing their legs when walking

A neuroprosthesis is a newer type of orthosis that uses electrodes (small metallic discs stuck to your skin) to deliver electrical currents to muscles in the legs or arms. The currents stimulate the muscles to move in the same way that the brain would normally.

A neuroprosthesis is not suitable for people with conditions that directly damage the nerves in the legs, such as motor neurone disease and Guillain-Barré syndrome. This is because the nerves will not react to the electrical currents.

Neuroprotheses are expensive. Depending on the complexity of the neuroprosthesis, it can cost from £1,300 to £32,000.

Using orthoses can be physically demanding, so they may not be suitable for everyone. Alternatively, you may decide to use both a wheelchair and an orthosis.

Assistive technology

There is also a wide range of assistive technology that can help a person with paralysis maintain their independence and improve their quality of life. Examples include:

environmental control units – voice-activated control units you can use to control things such as lighting, temperature or the telephone in your homespecially adapted computers – such as voice-activated computers, special keyboards that can be controlled using a stick placed in the mouth, and cursors that can be controlled with a laser beam attached to the head

The Disabled Living Foundation (DLF) has more information about assistive technology, and can also provide advice and support for people living with paralysis.

Driving

It may be possible for you to drive a car, even if you have limited muscle function in your hands and arms.

Devices can be used to adapt the controls of a car to meet the needs of a person with paralysis. For example, the pedals can be replaced with levers or an electrical switching system, and the steering wheel adapted so you steer using your wrists or arms, rather than having to grip it with your hands.

The Research Institute for Consumer Affairs (RICA) is a charity that provides independent research and information, and has good information about wheelchair-accessible vehicles.

Bladder and bowel management

Almost all types of spinal cord injury and many types of generalised paralysis result in the loss of normal bowel and bladder function. This is because nerves that control the bowel and bladder are located at the base of the spinal cord.

Most people use a catheter to empty urine from their bladder. A catheter is a thin, flexible tube inserted into the urethra (the opening in the penis or vagina that urine flows out of) or through a hole in the abdomen (tummy). 

The catheter is then guided into the bladder, allowing urine to flow through it and into a drainage bag.

There are many methods that can be used to manage a paralysed bladder. The recommended method will depend on your ability, the state of your bladder, and the resources available.

It is important to ensure your bladder is emptied regularly because an overly full bladder can trigger a serious complication called autonomic dysreflexia in high spinal cord injury

There are two main treatment options to help people with paralysis empty their bowel:

bowel retraining – this aims to improve the consistency of your stools and establish a regular time to empty your bowel, as well as helping you find ways of stimulating your bowel to empty

alternative methods, such as enemas – where liquid is injected into your bowel to help stimulate it to empty

A colostomy – an operation where a section of the bowel is diverted and attached to an opening in the abdominal wall

Neuropathic pain

Neuropathic pain is pain caused by nerve damage.

Many people with a spinal cord injury, and some with other types of paralysis, have long-term pain that persists for weeks, months, or sometimes years after the injury or incident that caused the paralysis.

Unlike most other types of pain, neuropathic pain does not usually respond well to ordinary painkillers, such as paracetamol or ibuprofen. Alternative medications are usually required, such as amitriptyline or pregabalin.

These types of medication can cause a wide range of side effects, so it can take time to identify one that is suitable and effective at controlling your symptoms without causing unpleasant side effects.

Possible side effects include a dry mouth, sweating, drowsiness and vision problems.

There have been reports of people having suicidal thoughts while taking amitriptyline. If this happens, you should contact your GP or go to your nearest hospital immediately.

It may be helpful to tell a relative or close friend you are taking amitriptyline and to ask them to let you know if they notice any changes in your behaviour.

Breathing difficulties

If you have had a spinal cord injury to the upper neck, your diaphragm will be paralysed. The diaphragm is a thin, dome-shaped muscle that helps you breathe in and out.

As your diaphragm will not be able to help you breathe, you will need breathing assistance from a ventilator. A ventilator is a machine that carries out the job of the diaphragm by controlling lung pressure.

This can be done in one of two ways, using either a:

negative pressure ventilator – where the ventilator creates a vacuum (a total lack of air) around the lung, which causes your chest to expand and pull in airpositive pressure ventilator – where the ventilator pushes oxygen directly into your lungs

Positive pressure ventilators are more widely used because they are usually smaller and more convenient. A positive pressure ventilator can either be:

invasive – where an incision is made in the throat and a tube inserted into the trachea (windpipe)non-invasive – where a tube is inserted into the nose, or air is supplied through a mouthpiece

Non-invasive ventilators carry a smaller risk of causing a lung infection such as pneumonia, but aren't suitable for people with more extensive paralysis who have difficulty swallowing.

An alternative to using a ventilator is a device called a phrenic nerve stimulator. The phrenic nerve controls the diaphragm. The device is surgically implanted in the chest and sends regular electrical impulses to the phrenic nerve, causing the diaphragm to contract and expand and fill the lungs with air.

Reduced cough

Another problem that affects most people with paralysis is that their ability to cough is reduced. This is because the cough reflex is triggered by muscles in the abdomen (tummy) and between the ribs pressing down on to the lungs.

If these muscles are paralysed, the force of a person's cough can be greatly reduced. This is potentially serious because a person's ability to cough enables them to clear their lungs of a build-up of mucus and other secretions. A reduced cough can cause the lungs to become congested, increasing the risk of a lung infection.

One technique used to compensate for this is known as an assisted cough. It involves a relative or carer pushing against the outside of your stomach while you attempt to cough.

There are also a number of devices available to help you cough. They usually consist of vests that can contract (squeeze) against your lungs, compensating for the loss of muscle action.

It is important you take precautions to reduce your risk of developing a lung infection by:

sitting up every day and turning regularly while lying down to prevent a build-up of phlegmmaking sure you cough regularlydrinking plenty of water to dilute any phlegm, making it easier to cough upavoiding smoking or being in close contact with people who smokegetting the flu vaccination and pneumococcal vaccination as they help reduce your risk of developing influenza and pneumonia

Spasticity and muscle spasms

Spasticity is a medical term that means abnormally stiff and rigid muscles. Many people with paralysis develop spasticity and involuntary muscle spasms (where muscles cramp and contract).

Spasticity and muscle spasms are usually caused by the section of the spinal cord below the point of the injury "misfiring" and sending abnormal signals to the limbs.

In some cases, spasticity and muscle spasms can be useful. For example, if you have partial paralysis in your legs, the stiffness in your muscles may make your legs easier to control.

Some people also find that a series of muscle spasms makes it easier for them to empty their bladder or bowel. But in other cases, spasticity and muscle spasms can be painful, affect mobility and interfere with daily activities.

Treatments for spasticity and muscle spasms are discussed below.

Muscle relaxants

The first type of medication you may be prescribed is a muscle relaxant, such as baclofen, tizanidine or dantrolene, usually taken in tablet form.

Sedatives like diazepam should be avoided, except in severe cases. All of these medicines may cause sedation as a side effect.

Botulinum toxin

If muscle relaxants are not effective, an injection of botulinum toxin (Botox) may be given for localised spasms. It works by blocking the signals from the brain to the affected muscles.

The effects of the injection usually last for up to three months. The treatment is most effective when used in conjunction with a programme of stretching and physiotherapy.

Intrathecal baclofen therapy

Another possible treatment is intrathecal baclofen therapy. This involves surgically implanting a small pump on the outside of the body connected to the spinal cord.

The pump delivers regular doses of baclofen directly to the spine. It blocks some of the nerve signals that cause muscle stiffness.

Complications of paralysis 

A person with paralysis can develop a number of complications, including autonomic dysreflexia, sexual problems and depression.

Autonomic dysreflexia

Autonomic dysreflexia is a potentially life-threatening complication. It can affect people with paralysis as a result of a spinal cord injury at the middle of the chest or higher. 

It is commonly seen in tetraplegia (where both the arms and legs are paralysed, also known as quadraplegia).

Autonomic dysreflexia is caused by a problem with the autonomic nervous system, the part of your nervous system that regulates many of the body's functions you don't have to think about, such as blood pressure, digestion and breathing.

It occurs when something interferes with the normal function of your autonomic nervous system. Your nervous system will send a signal to your brain to find out how to deal with the irritant. However, because of the injury to your spinal cord, the signal will be unable to reach your brain.

The blocked signal will then trigger a series of abnormal reflexes, which cause your autonomic nervous system to raise your blood pressure and slow your heartbeat.

Symptoms of autonomic dysreflexia

Signs and symptoms of autonomic dysreflexia include:

a severe, pounding headachean intense feeling of anxiety and apprehensionintense sweating above the level of your injurytightness in your chestred blotches on your skin above the level of your injurya slow heartbeat (less than 60 beats a minute)dilated (widened) pupilsgoosebumpshigh blood pressure (hypertension)

If it's not treated, autonomic dysreflexia can cause seizures and bleeding inside the brain, which can be fatal.

Triggers of autonomic dysreflexia

The most common trigger of autonomic dysreflexia is a problem with the bladder, such as:

a urinary tract infection – an infection of the kidneys, bladder, ureter or urethratoo much urine in the bladder a blocked catheter (the tube used to drain the bladder)the bag used to drain the bladder being too fullbladder stones

Other triggers for autonomic dysreflexia include:

constipation haemorrhoids (piles)pressure ulcersingrown toenailburns, including sunburnsexual activityperiod cramps labour and giving birthbone fractures

Treating autonomic dysreflexia

The first thing to do if you suspect autonomic dysreflexia is to sit up (if possible) or raise your head upright. You should also lower your legs if you can.

Identifying the trigger is the next important step. The most common trigger is a bladder problem, so you should check your catheter system first. Check whether:

your catheter is blocked or twistedyour drainage bag is fullthe catheter is fully inserted into the drainage bagthe drainage bag is higher than your bladder

If you have a full bladder or are unable to pass urine and you do not have a catheter attached, you may need urgent urinary catheterisation.

If your bladder does not appear to be the trigger, check your bowel next. Use your finger or ask your trained carer to do so to check whether there are any hardened stools in your back passage. The use of lubricated gloves is recommended. Any large, hard stools detected should be gently removed.

If neither your bladder or bowel seem to be the trigger, check your skin for any pressure ulcers or an ingrown toenail. Loosen any clothing from skin or toes that appear to be damaged.

If you are unable to identify the trigger or relieve the symptoms using the advice above, contact your care team immediately. If this is not possible, call NHS 111.

Depression

Coming to terms with paralysis, particularly if it occurred suddenly and unexpectedly, can be difficult and traumatic. Many people go through the classic stages of grief, as described below:

denial – initially, you may refuse to believe your condition is incurable and think you will be able to continue with your former lifestyle

anger – you may lash out at friends, family or medical staff

bargaining – you may try to bargain with your doctors, asking for any sort of "miracle cure

"depression – you may lose all interest in life and feel your situation is hopeless

acceptance – in time, most people come to terms with being paralysed and begin to adapt to living with the condition

Some people with paralysis find it difficult to reach the acceptance stage and continue to be depressed. It is estimated about 20 to 30% of people with permanent paralysis are affected by depression.

It is important not to ignore any signs or symptoms of depression. As well as affecting your rehabilitation, symptoms can also quickly worsen if they are not treated promptly. Read more about depression.

People who experience depression after paralysis usually come to terms with the condition. One study, which looked at people living with paraplegia (paralysis of the lower limbs) for many years, found 83% reported having either an above average or average quality of life.

Sex life and fertility

Paralysis can often have an impact on a person's sex life and fertility. However, even if you have severe paralysis, it does not necessarily mean you will be unable to have children or sexual intercourse.

Paralysis can sometimes affect a man's ability to get and maintain an erection, as well as his ability to ejaculate sperm.

Erection

There are two types of erection:

a reflex erection – caused by something touching your penis or another sensitive part of your body

a psychogenic erection – caused by sexual thoughts or looking at sexually explicit images 

As the nerves that control the reflex erection are located at the base of your spine, your ability to achieve this type of erection will usually be retained, even if your paralysis is severe.

However, the nerves that control a psychogenic erection are located much higher up the spine, so men with high-level partial paralysis and almost any type of complete paralysis are unlikely to be able to have a psychogenic erection.

If you are only able to have a reflex erection, it will still be possible for you to have sex, although you may find it difficult to maintain an erection for a prolonged period of time. This is known as erectile dysfunction.

Treatment options for erectile dysfunction include medication, such as sildenafil (Viagra), which increases the blood flow to your penis, and penis pumps, which create a vacuum and cause blood to flow to your penis.

Read more about erectile dysfunction.

Ejaculation

The type and location of your paralysis will also affect whether you will be able to ejaculate sperm.

If you lose the ability to ejaculate but you want to have children, a number of different techniques can be used to obtain a sperm sample.

The sperm can then be used in fertility treatment, such as intrauterine insemination (where a sample of sperm is implanted into a woman's womb through a tube).

A widely used technique is known as penile vibratory stimulation, where a specially designed vibrator is placed against the underside of the penis.

The vibrator stimulates the nerve endings of the penis, triggering ejaculation. The process usually takes about 10 to 30 minutes to complete.

As it is important to store the sperm sample as quickly as possible, penile vibratory stimulation is usually carried out in a private room at a fertility clinic.

If this is unsuccessful, an alternative technique known as rectal probe electroejaculation can be used. Again, this is usually carried out at a fertility clinic.

During the procedure, an electric probe is inserted into the rectum (back passage). The probe delivers a small electrical pulse to the rectum, which stimulates the nerves and triggers an ejaculation. The sperm can then be collected.

Women

In women with paralysis, physical libido (sex drive) and fertility are usually unaffected.

Many women may experience a reduction in their sex drive because of concerns about their body image or having to use a bladder or bowel control system.

You will probably find your vagina no longer becomes lubricated when you are sexually aroused. This is because nerves located higher up the spine trigger the process of lubrication.

You can compensate for this by using an artificial water-based lubricant, such as KY jelly. Do not use petroleum jelly (Vaseline) as it will irritate your vagina.

There is usually no reason why a woman who is paralysed and pregnant cannot have a vaginal delivery during childbirth.

Pregnant woman with a spinal cord injury at T6 or higher have an increased risk of developing autonomic dysreflexia, so it is important to be aware of the symptoms and, if you experience them, that you inform your GP or midwife immediately