Definitions of quadriplegic: "quad".

* a person who is paralyzed in both arms and both legs;
* Quadriplegia is caused by damage to the spinal cord at a high level (e.g. cervical spine). The injury causes the victim to lose either total or partial use of the arms and legs. The condition is also termed tetraplegia; both terms mean "paralysis of four limbs". The loss of sensation and movement may not be complete with some sensation and movement being retained in parts of the arms and legs.

Severity depends on which cervical vertebra is injured and the extent of the injury. An individual with an injury to C1 (the highest cervical vertebra just below the base of the scull) will likely be paralyzed and lose function from the neck down and be ventilator dependent. An individual with a C7 injury will likely be paralyzed and lose function from the chest down but still retain use of the arms and some use of their hands.

Quadriplegics can have high or low injuries, depending on where the injury is on the spinal cord. The higher the injury, generally the less function a person will have. Christopher Reeve was a high quad, for example, and needed assistance to breathe.
He was a C-1 quad, one vertebra just below the base of the scull.

Definitions of Paraplegic: "paras"

Paraplegia involves a loss of sensation and movement in the legs and in part or all of the trunk. This varies according to the level of the injury. Generally, the lower the injury, the less the loss of movement and sensation. Paraplegia usually results from an injury to the spinal cord in the mid and lower back.

Paraplegics, who are paralyzed from the waist down, involving loss of sensation and movement in the legs and in part or all of the trunk with use of their arms and hands, refer to themselves as "paras"

More than 54 percent of spinal cord injuries are the result of vehicular collisions. More than a quarter result from other medical conditions and sports injuries. Falls make up about 18 percent.

A spinal over view