SCI: The Basics
The goal of the SCI Lawyers website is to help people with spinal cord injuries navigate the strange new world of paralysis, and to find the tools to move forward with self-determination and independence.
Spinal cord injury (SCI) is usually the result of forceful trauma, most commonly related to motor vehicle accidents, sports injuries, falls, acts of violence, or medical wrongdoing. SCI is sudden and dramatic, and happens to about 12,000 people a year, or roughly 1,000 in Southern California. Most injuries occur to men (about 80 percent) and injuries happen mostly to people in their 20s. The consequences are life-changing and affect not just the injured but also his or her family and loved ones.
An injured person with SCI, however, can live a long and healthy life, fully active in work, family and community if: (1) connected to good resources; (2) able to obtain medical care; and (3) imbedded in a community of people who understand living with SCI.
SCI Disrupts Nerve Communication
The spinal cord, a bundle of nerve fibers that extends from the base of the brain down to the tailbone, is well-protected by the backbone. However, trauma can exceed the strength of the backbone. While you may hear that a person’s spinal cord was “severed,” that is rarely the case except in knife or gunshot wounds. In most cases of SCI, the cord is pinched, or bruised, or its blood supply is otherwise compromised. These mechanisms disrupt the transmission of commands from the brain through the nerves to the muscles below the area of injury, and it also interrupts sensory messages from the body back to the brain.
The Level of the Injury Determines Function
One of the first things you hear about SCI is level of injury. This is important because location of a spinal cord lesion determines the functions a person can be expected to retain. The higher up the spinal cord the injury, the higher and more devastating will be the level of impairment. A rough gauge of function and SCI can be made using a schematic, actually used for sensation loss, called a dermatome map. See illustration, from the American Spinal Injury Association, below. A spinal cord injury in the neck (cervical injuries) will involve substantial loss of movement and sensation loss in the arms (the higher the level, the greater the loss) and of the lower extremities. SCI in the level of the upper back (thoracic injuries) involve some but lesser loss of arms, hands and fingers, and trunk but still with large loss of ability to move the lower extremities. Almost all SCI injuries affect the legs and feet, as well as bladder, bowel and sexual function and higher levels also affect the lungs.
People who injure their spinal cords in the neck area are commonly called quadriplegics, (plegia, or paralysis in 4 levels), or quads for short. The medical term for this is tetraplegia. The majority of SCI cases in the U.S. result in quadriplegia.
Persons who have lower thoracic and even lower (lumbar) SCIs usually retain arm function and are called paraplegics, or paras.
A very high cervical injury, such as that of actor Christopher Reeve, who had a C2 injury, affects breathing and requires mechanical ventilation. Reeve was unable to move or feel any part of his body except his head; he required assistance for eating, dressing, bathing, hygiene, everything except for piloting his power wheelchair with a sip and puff controller. If persons like Reeve are injured just a few spines lower on their backbone – a matter of an inch or two – they retain some ability to move their arms, and perhaps fingers, thus retaining some ability for self-care, and thus a larger degree of independence.
Complete vs. Incomplete Spinal Cord Injury
No two spinal cord injuries are exactly alike. Two people who injure their cord at the same level can have very different outcomes. One might recover some ability to walk while the other cannot move a muscle below the injury. Besides level of injury, the other major factor in functional loss is the degree of damage that the cord actually sustains. How badly was the cord squeezed, crushed or bruised?
Injured persons are quickly assessed to determine the extent of the damage; doctors use a detailed chart called the ASIA Impairment Scale to measure remaining motor (movement) function. A motor score is derived by testing ten muscle groups in the elbow, wrist, fingers, hips, knees, ankles and toes. Sensation also is measured and scored, using light touch or pinprick across the 28 sensory zones in the body, set forth in Figure 1.
If a person has no motor or sensory function, that’s called a complete injury. There are many degrees of incomplete injury.
In many cases of SCI people improve beyond their initial diagnosis. Generally, however, improvement plateaus after 6-18 months. Historically, patients labeled as having incomplete injury stand a much better chance of getting better than those labeled complete.
The good news is that there are more incomplete injuries these days than complete. This often is attributed to better emergency management and more specialized acute care.
Even with a diagnosis of complete SCI, outcome is less certain than it once was. Moreover, current research and devices are allowing for some movement in such patients, as well as some recovery in bowel, bladder and sexual function.