Any damage to the spinal cord is a very complex injury. Each injury is different, and injuries can affect the body in many different ways. Following is a brief summary of changes that can take place after a spinal cord injury.
The Normal Spinal Cord
The spinal cord is a part of your nervous system. It is the largest nerve in the body. Nerves are cordlike structures made up of nerve fibers. The spinal cord has many nerve fibers. These nerve fibers carry messages between the brain and different parts of the body. The messages may be to tell a body part to move or to bring messages of feeling or sensation (such as hot and cold) to the brain. The body also has an autonomic nervous system. It controls the involuntary activities of the body such as blood pressure, body temperature and sweating.
The spinal cord can be compared to a telephone cable. It connects the main office (the brain) to many individual offices (parts of the body) by telephone lines (nerve fibers). The spinal cord is the path that messages use to travel between the brain and other parts of the body.
Because the spinal cord is so important, it is surrounded and protected by bones called vertebrae. The vertebrae, or backbones, are stacked on top of each other and form the number one support for the body. The spinal cord runs through the middle of the vertebrae.
The spinal cord is about 18 inches long. It extends from the base of the brain, down the middle of the back to about the waist. The spinal cord is divided into four sections. The top portion is called the cervical area and it has 7 vertebrae. The next section is called the thoracic spine. The thoracic spine includes the chest area and has 12 vertebrae. The lower back section is called the lumbar area. There are 5 lumbar vertebrae. The bottom section has 5 vertebrae and is called the sacral area.
The Spinal Cord After An Injury
A spinal cord injury can occur either from an injury or from a disease to the vertebral column or spinal cord itself. In most spinal cord injuries, the backbone pinches the spinal cord. The spinal cord may become bruised or swollen. The injury may actually tear the spinal cord and/or its nerve fibers. After a spinal cord injury, most nerves above the level of injury keep working like they always have. Below the level of injury, the spinal cord nerves can no longer send messages between the brain and the parts of the body like they did before.
The doctor examines the individual to understand what type of damage has been done to the spinal cord. An x-ray or MRI shows where the damage has occurred. The doctor may do a "pin prick" test to see what feeling the person has all over his or her body - this helps determine the level of sensation. A doctor may also ask, "what parts of the body can you move?" - this helps determine the level of motor function. These tests are important because they tell the doctor what nerves and muscles are working.
Each spinal cord injury is different. A person's injury is described by its type and level.