Quadriplegia and Tetraplegia
The term "quadriplegic" is derived from two different words from two different languages, Latin and Greek. The word "quadra", when translated from Latin means "four", this relates to the number of limbs. "plegic", is derived from the Greek word "plegia", which when translated, means "paralysis".
When the two words are combined together, you have "quadraplegia".
"Tetra" is derived from the Greek word for "four". "para" is derived from the Greek word for "two" Hence: tetraplegic and paraplegic.
In Europe, the terminology for 4 limb paralysis has always been tetraplegia. The Europeans would never dream of combining a Latin and Greek root in one word.
Quadriplegic and quadriplegia are the terms used mainly in America to describe paralysis of all four limbs. In 1991, when the American Spinal Cord Injury Classification system was being revised, the difference in names was discussed. The British are more aware of Greek versus Latin names. Since Plegia is a greek word and quadri is Latin, the term quadriplegia mixes language sources.
Upon review of the literature, it was recommended that the term tetraplegia be used by the American Spinal Cord Association so that there are not two different words in English referring to the same thing.
Quadriplegia or tetraplegia is when a person has a spinal cord injury above the first thoracic vertebra (T1), paralysis usually affects the cervical spinal nerves, C1 to C8 resulting in paralysis of all four limbs. This may result in partial or complete paralysis of the arms as well as complete paralysis of the legs.
There are 7 cervical vertebrae in the neck, but 8 spinal nerves as the spinal nerves exit the spinal cord above the vertebrae.
In addition to the arms and legs being paralyzed, the abdominal and chest muscles will also be affected resulting in weakened breathing and the inability to properly cough and clear the chest. Breathing will be dependant on the diaphragm, or in severe cases, a ventilator. People with this type of paralysis are referred to as quadriplegic or tetraplegic.
Level of injury (Lesion)
The level of injury, otherwise known as a lesion, is the exact point in the spinal cord at which damage has occurred. Damage may take the form of scar tissue, or the cord may be compressed due to a damaged vertebrae or inter vertebral disc. The levels of spinal nerves are determined by counting the nerves from the top of the spine downwards, and these nerves are grouped into four different area's. These are the cervical, thoracic, lumbar and sacral parts of the spinal cord.
These area's are important, as damage to the spinal cord at these points directly determines how groups of muscles, organs and sensations will be affected.
Determining how the spinal cord has been damage is also a consideration when evaluating a spinal cord injury. There are two types of lesion, these are a complete injury and an incomplete injury. Someone with a complete injury will have a complete loss of muscle control and sensation below their level of lesion. An incomplete injury is where maybe only the muscles have been paralyzed, or where there is impaired sensation after a Spinal Cord Injury
The degree to which a persons body will work following a spinal cord injury resulting in quadriplegia or paraplegia will depend on the level of injury, and whether the injury was complete of incomplete. In order to show what functionality will be possible following a complete spinal cord injury, we have put together the most common abilities for varying degree's of paralysis.
Click the spinal cord injury levels below for a comparison of complete injury levels and abilities
These abilities are not definitive, and slight variations may be present due to body weight, existing medical issues and post injury ageing.
Incomplete Spinal Cord Injuries
Anterior Cord Syndrome
Anterior Cord Syndrome: is when the damage is towards the front of the spinal cord, this can leave a person with the loss of motor function, impaired ability to sense pain, temperature and touch sensations below their level of injury. Pressure and joint sensation may be preserved. It is possible for some people with this injury to later recover some movement if motor recovery is evident days after the initial injury.
Central Cord Syndrome
Central Cord Syndrome: is when the damage is in the centre of the spinal cord. This typically results in the loss of function in the arms, but some leg function may be preserved. There may also be some control over the bowel and bladder. It is possible for some recovery from this type of injury, usually in the legs, gradually progressing upwards.
Posterior Cord Syndrome
Posterior Cord Syndrome: is when the damage is towards the back of the spinal cord. This type of injury may leave the person with good muscle power, pain and temperature sensation, however they may experience difficulty in coordinating movement of their limbs.
Brown Sequard Syndrome
Brown-Séquard syndrome: is when damage is towards one side of the spinal cord. This results in impaired or loss of movement to the injured side, but pain and temperature sensation may be preserved. The opposite side of injury will have normal movement, but pain and temperature sensation will be impaired or lost.