SPINAL CORD INJURY

DEFINITION

Spinal cord injury is damage to the spinal cord that causes loss of sensation (feeling) and motor (muscular) control.

DESCRIPTION

About ten thousand new spinal cord injuries (SPI) occur each year in the United States. About 250,000 people currently have this condition. Spinal cord injury can happen to anyone at any time of life. The typical patient, however, is a man between the ages of nineteen and twenty-six. The most common causes of SPI are motor vehicle accidents (which are responsible for 50 percent of all cases), a fall (20 percent), an act of violence (15 percent), or a sporting accident (14 percent). Alcohol or drug abuse is involved in many of the accidents that result in spinal cord injuries.

About 6 percent of those who suffer injury to the lower spine die within a year while approximately 40 percent of those who suffer injury to the upper spine die within a year.

CAUSES

The spinal cord is a long rope-like piece of nervous tissue. It runs from the brain down the back. It is contained within the spinal column. The spinal column consists of a set of bones known as vertebrae (pronounced VUR-tuh-bray).

Pairs of nerves travel from the spinal cord to muscles in the arms, legs, and other parts of the body. Messages travel from muscles to the spinal cord and then to the brain along one set of nerves. Messages travel in the opposite direction, from brain to spine to muscles, along the other set of nerves.

Each pair of nerves is connected to the spinal cord in the space between two adjacent vertebrae. The nerves are named for the vertebrae where they enter the spinal cord. The five sets of nerves connecting to the spinal cord are defined as follows:

• C1-8 nerves enter the spine near the eighth cervical vertebrae, located in the neck.
• T1-12 nerves enter the spine near the thoracic vertebrae, located in the chest.
• L1-5 nerves enter the spine near the lumbar vertebrae, in the lower back.
• S1-5 nerves enter the spine through the sacral vertebrae, located in the pelvis region.
• The coccygeal nerves (pronounced kock-SIHJ-ee-uhl) enter the spine through the coccyx, or tailbone.

Injury to the spinal cord may damage any one or more of these nerves. When nerves are damaged, messages can not travel from the brain to the body's muscles, or from the muscles to the brain. For example, a person may lose their sense of touch if nerve messages are not able to travel from the fingers to the brain. Or a person may lose the ability to walk if nerve messages can not travel from the brain to leg and foot muscles. Other functions, such as urination, sexual function, sweating, and blood pressure, may also be affected.

The spinal cord can be damaged in many ways. A sudden and violent jolt can cause a temporary spinal concussion. The symptoms of a concussion usually disappear completely in a few hours. Or the spinal cord can suffer a contusion. A contusion is a bruise that can cause bleeding in the spinal column. Such bleeding can produce pressure on nerve cells that can cause those cells to die.

Spinal compression is caused when an object such as a tumor or abnormal growth puts pressure on the spinal column. This compression can cause the death of nerve cells.

Some injuries can cause a laceration (tear) in the spinal column. In the most serious cases, the spinal cord can be torn apart. This type of injury is known as a spinal transection. A spinal cord injury can consist of any one or combination of these types of damage.

SYMPTOMS

The symptoms of SCI depend on two factors: where the damage occurs and how serious it is. For example, damage below the T1 nerves causes loss

Former Texas Christian University football player Matt Moore suffered a paralyzing spinal injury during football practice. About 14 percent of spinal cord injuries are caused by sporting accidents. (Reproduced by permission of

AP/Wide World Photos

)

of feeling and paralysis in the legs and the lower body. The T1 nerves lie at the base of the ribs. Arm and upper body movement is not affected by this kind of injury.

Damage to nerves below the C3 level of nerves may cause loss of feeling and paralysis of the arms as well as the legs and upper body. The C3 nerves are located in the middle of the neck. This kind of injury may also damage a person's chest muscles, making breathing difficult, but not impossible.

Damage above the C3 level may cause loss of feeling and paralysis throughout the body below the neck. A person with this kind of damage is not able to breathe on his or her own.

A spinal transection causes complete loss of feeling and muscle control. A person is completely paralyzed in the part of the body below the injury. For example, a person whose spinal cord is severed at T1 will be unable to move his or her legs or the lower part of the body. If the spine is injured but not severed, some feeling may remain.

Spinal cord injuries can cause many other kinds of symptoms, including:

• Blood clots. Blood clots may form in veins when an arm or leg has been inactive for a long time. The clot may break loose and cause damage to the heart or lungs.
• Pressure ulcers. Pressure ulcers are sores that develop when a person can not move for long periods of time.
• Muscle stiffness. Spinal cord damage may make it impossible to move muscles normally. After a while, the muscles tend to become tight and shortened. This process is called a contracture. Eventually, the muscles become frozen in an abnormal and awkward position. When this happens, the muscle is said to be spastic.
• Calcium deposits in muscles and tendons. Spinal cord injury may cause the growth of bone-like material in muscles and tendons. This growth may produce swelling, redness, heat, and stiffness in a muscle.
• Failure of autonomic responses. Some body organs regulate themselves. The heart is an example. It automatically increases or decreases its rate of beating based on outside conditions, such as temperature. A person doesn't have to think about making these changes. They occur automatically. They are known as autonomic (self-controlling) responses. SCI can damage these systems. An organ may not respond the way it is supposed to. For example, pressure on the skin can cause organs to produce wild and uncontrolled responses. The patient may experience terrible headaches, nausea, anxiety, seating, and goose bumps. In extreme cases, these abnormal responses may lead to seizures, loss of consciousness, and even death.
• Loss of bladder and bowel control. Bladder and bowel control are maintained by the use of certain muscles. Young children have to learn how to use these muscles when they become toilet-trained. SCI can cause damage to the nerves that control these muscles. A person may urinate or defecate without wanting to, or may not be able to urinate or defecate when he or she needs to.
• Sexual dysfunction. Maintaining an erection requires control over muscles in the penis. If nerves are damaged, this control may not be possible. A man may not be able to have an erection. Sexual intercourse may become impossible. Women with spinal cord injuries, however may still be able to become pregnant, and can usually deliver a child with proper medical care.

DIAGNOSIS

Symptoms such as those listed above may suggest the presence of spinal cord injury. A final diagnosis is usually made using some form of imaging technique. An imaging technique is any method for studying the structure of an internal organ. For example, X rays may show the location and extent of damage to the spinal cord.

TREATMENT

The first step in treating spinal cord injuries is immobilization. Immobilization involves the use of splints, braces, or a cast to prevent the patient from moving. It keeps a spinal tear or injury from becoming worse. Steroid injections (shots) may be given to the patient as well. Steroids reduce inflammation and swelling, and this can prevent further damage to cells and tissues in the spinal cord. Immobilization and drug injections have greatly reduced the severity of spinal cord injuries in the last few decades.

There are currently no treatments that will make a spinal cord grow back to its normal condition. The most that can be done is to help people with spinal cord injuries avoid complications and to make the best use of those bodily functions they still control. Programs of this type often require a variety of professional workers, including a neurologist (specialist in nerve disorders), psychiatrist or psychologist, physical therapist and occupational therapist. Depending on the type of injury, a patient might also need the help of a respiratory therapist, speech-language specialist, nutritionist, special education teacher, or recreation therapist. Support groups also provide important information, advice, and emotional support for SCI patients. Support groups are made up of other individuals who have the same medical problem.

Some specific forms of rehabilitation (recovery) treatment include the following:

Paralysis and loss of feeling

Many patients with SCI can recover at least some of their ability to move. Physical therapists can teach patients how to use muscles that are still functional to take over for those that are not. The therapist can also help with exercises that will strengthen muscles that can still move. He or she also suggests equipment that may aid the patient's ability to move, such as braces, canes, or wheelchairs.

An occupational therapist teaches patients how to perform normal daily activities, such as eating and caring for oneself. The therapist may suggest changes in the person's home or work to make routine activities easier to perform.

A respiratory therapist helps SCI patients learn how to function with a weakened breathing system. For example, patients may learn new methods of coughing to make sure that disease-causing agents are eliminated from the lungs.

Pressure ulcers

Pressure ulcers (bedsores) often develop when a person is confined to bed for long periods of time. The sores can be prevented by turning the patient every two hours. Special chairs and mattresses are available that make pressure ulcers less likely.

Contracture and spasticity

Patients can be taught exercises that keep their muscles from becoming too stiff. In some cases, drug injections can help relax the muscle tissue. In extreme cases, surgery may be necessary to cut and/or replace tendons that have become too stiff.

Abnormal calcium deposits

A drug known as etidronate disodium (Didronel) helps control the way calcium is used in the body. When injected into SCI patients, it prevents calcium from depositing in muscles and tendons. In some cases, doctors may decide to remove abnormal calcium deposits by surgery.

Failure of autonomic responses

Patients and their families should learn to detect signs that autonomic responses are failing.

If not treated quickly, these failures can cause serious damage or death. Patients may need to be protected from conditions, such as exposure to the sun and pressure on the skin that may cause abnormal responses.

Sexual dysfunction

Counseling may help SCI patients to learn other forms of sexual behavior than traditional forms of intercourse. These alternative sexual behaviors can often be as satisfying as those with which the patient was familiar.

PROGNOSIS

The prognosis for spinal cord injury depends on two factors: the location of the injury and its extent. Injuries of the neck above the C4 nerves are the most dangerous. Patients often lose the ability to breathe on their own. The infection of the respiratory (breathing) tract that can result is the leading cause of death among patients with this type of spinal cord injury.

Overall, 85 percent of SCI patients who survive the first twenty-four hours after being injured are still alive ten years after the injury. How much control over bodily functions a patient recovers is impossible to predict. There more moderate the injury to the spinal cord, the greater chance for recovery.

PREVENTION

The vast majority of spinal cord injuries occur during accidents. As a result, it is difficult to prevent such injuries. Perhaps the most important step one can take is to use safety precautions that are available. For example, one should always wear a seat belt when traveling in a car. Also, one should wear protective equipment, such as helmets, when engaging in certain types of sports such as bike riding, roller-blading, and mountain climbing.

FOR MORE INFORMATION

Books

Reeve, Christopher. Still Me. New York: Random House, 1998.

Senelick, Richard C., and Karla Dougherty. The Healthsouth Spinal Cord Injury Handbook for Patients and Their Families. Birmingham, AL: Healthsouth Corporation, 1998.

Williams, Margie. Journey to Well: Learning to Live After Spinal Cord Injury. Newcastle, CA: Altarfire Publishing, 1998.

Organizations

The National Spinal Cord Injury Association. 8300 Colesville Road, Silver Springs, MD 20910. (301) 588–6959. http://www.erols.com/nscia.

Other

"Ask NOAH About: Spinal Cord and Head Injuries." NOAH: New York Online Access to Health. [Online] http://www.noah.cuny.edu/neuro/spinal.html (accessed on October 31, 1999).