Spinal disorders are a group of conditions that involve a loss of normal structure and function in the spine. These common disorders are associated with the normal effects of aging, but also may be caused by infection, tumors, muscle strains, or arthritis. Pressure on the spinal cord and nerve roots associated with spinal degeneration may be caused by disc displacement or herniation; spinal stenosis, a narrowing of the spinal canal; or osteoarthritis, cartilage breakdown at spinal joints. Spinal disorders and especially back and neck pain affect more people and have greater impact on work capacity and health-care costs than any other musculoskeletal condition. Degenerative diseases of the spine are the most common causes of back and leg pain. Usually it is a process that slowly progresses over time, although in cases of acute disc herniations the symptoms can occur suddenly. An acute spinal injury or acute spinal cord injury is an injury to your spinal cord that results from a 1-time traumatic incident. Acute spinal cord injury is diagnosed by evaluation of your neurological symptoms and diagnostic imaging studies (CT and MRI). In an incomplete injury there is some level of preservation of function below the level of the injury, even if it is represented only by some sensation or weak movement in an arm or leg. In a complete there is a total loss of motor and sensory function due to severe damage to the spinal cord.