Considering the medical definition of paralysis, there is really only one cause of paralysis — a loss of communication between the brain and the spinal cord. There are, however, some common causes of paralysis or things that commonly result in paralysis. Those causes include accidents and having a stroke. Motor vehicle accidents, falls, assault and sports-related injuries are the most common causes of paralysis, because of the trauma to the head, neck and back that can be sustained. Injury to these parts of the body often involve injury to the brain and the spinal cord.
The various causes of paralysis can actually be broken down into more specific causes. For example, assault against someone that involves a stabbing in the back could easily injure the person's spinal cord. Hitting someone in the arm, however, would not figure among the most common causes of paralysis, although it also is an assault. Automobile accidents are particularly dangerous because of the high risk for trauma to the brain and spinal cord that exists. Danger exists regardless of the side of the car that is hit or whether the person inside the vehicle is the driver or a passenger.
Pedestrians being struck by motor vehicles also might be considered one of the most common causes of paralysis, because they can suffer injury to the brain and spinal cord just like automobile passengers. It is no wonder that falls from a ladder or down a flight of stairs is one of the most common causes, because they also can be fatal. Athletes, particularly those who participate in physically demanding sports such as wrestling, skiing, diving, hang gliding and football, almost always run a higher risk of sustaining injury to the brain and spinal column.
Just as there are various causes of paralysis, there also are various types of paralysis. Hemiplegia is the paralysis of the leg, trunk and arm on the same side of the body. Paralysis in the lower body is called paraplegia, and quadriplegia is paralysis of all four limbs. Any of these conditions can present with injury to the spinal cord, depending on what section of the cord is damaged.
Although injury to the spinal cord can and often does lead to some type of paralysis, learning what to do and what not to do in the event of an accident can make the difference in whether a victim is left paralyzed. For example, knowing the danger of improperly moving an accident victim should be common knowledge so that someone with good intentions does not cause harm. Any type of unexplained paralysis or weakness in the body should be cause to consult a medical doctor.