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 hand
- paralysis 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 C7
- 12 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 breathing
- someone with a C7 spinal cord injury will be able to extend their elbows and may have some movement in their fingers
- someone 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 wheelchair
- someone 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