Spinal Cord Injury
Overview
Spinal cord injury is a serious condition that affects lives dramatically. The spinal cord is a column that runs from the base of the brain to the lower back. With the brain, it makes up the central nervous system.
The spinal cord is critical for sending messages to and from the brain and other parts of the body. Important body functions like breathing, digestion, movement, and elimination are all associated with nerves of the spinal cord.
The spinal cord is protected by 33 bones called vertebrae, which are stacked one on top of the other. Messages between the brain and other parts of the body travel along pathways, called axons, which branch out from the spinal cord to other areas. Axons are long fibers of nerve cells (neurons) that carry outgoing messages.
The spinal cord often is injured when vertebrae are broken or fractured and axons are damaged. Damage prevents messages from getting through, causing a number of problems. Bleeding, swelling, and the body's chemical responses contribute to waves of additional damage that can continue for days or even weeks following the injury.
Much of the prognosis and recovery depends on the location and severity of the injury. Some patients recover well and others may be paralyzed for life. Generally, patients experience more paralysis when the injury is higher in the spinal column.
If a patient loses function in all 4 limbs, the condition is called quadriplegia or tetraplegia. Paraplegia occurs when function is lost in the lower body only.
Types of Spinal Cord Injury
Spinal cord injuries are termed complete or incomplete (also called partial) depending on how much of the spinal cord has been damaged. With a complete injury, messages cannot travel to and from the brain and there is no feeling or movement below the injury. An incomplete injury is less severe. This type of spinal cord injury allows for some messages to get through and for limited sensory and motor ability.
Injuries can also be classified as traumatic or nontraumatic. Traumatic injuries are sudden, often from a strong force that causes immediate damage. Nontraumatic injuries tend to develop more slowly from diseases (e.g., arthritis, cancer), bleeding, and infections.
Incidence and Prevalence
According to the Spinal Cord Injury Information Network (June 2006), approximately 11,000 people suffer spinal cord injuries in the United States each year and about 253,000 people in the United States are currently living with such injuries. Approximately 52% of spinal cord injuries result in quadriplegia or tetraplegia and about 42% result in paraplegia.
Risk Factors and Causes
While spinal cord injuries can happen to anyone, certain populations may be more prone to them. According to the Mayo Clinic, 80% of spinal cord injuries in the United States occur in men. Age is another risk factor. People aged 18-35 are more likely to sustain spinal cord injuries from car or motorcycle accidents, and the elderly are more likely to become injured in falls.
Athletes, particularly gymnasts, skiers, hockey players, divers, and surfers are at increased risk. Patients with diseases that affect the bones and joints are also more susceptible to spinal cord injuries.
The Mayo Clinic notes that approximately 50% of spinal cord injuries are caused by motor vehicle accidents and approximately 24% result from falls. Acts of violence (primarily gunshot wounds) account for approximately 11% of cases and sports and other recreational activities cause about 9% of spinal cord injuries. Diseases such as cancer, arthritis, and osteoporosis are another common cause.
Prevention
There are many ways to prevent spinal cord injuries. In motor vehicles, drivers and passengers should always wear seat belts and make sure that children are properly secured in a child safety seat. Children under age 12 should always ride in the back seat. People who are under the influence of alcohol or drugs should not drive; nor should any passenger get into a car with an impaired person at the wheel.
Elderly people are more prone to spinal cord injuries from falls. Many modifications can be made in the home to minimize this risk, including securing banisters and railings, and installing grab bars in the bathroom, and non-slip bathmats on both the bathroom floor and the shower. Keeping floor space clear and wearing non-slip shoes can help prevent tripping.
Homes with children should be equipped with safety gates and window guards to prevent falls down stairs and out windows.
Athletes can help protect themselves by wearing proper safety gear. Helmets should be worn when playing football, hockey, baseball, and softball. Bikers, motorcyclists, skiers, horseback riders, and skaters should always wear helmets as well. Swimmers should make sure that water is deep enough for diving and gymnasts should always use spotters.
Firearms should be kept unloaded in a locked case and ammunition should be locked separately. Members of the community can help prevent spinal cord injuries by educating the public, particularly children, on how to stay safe. Coaches can insist that their athletes follow proper procedures regarding safety gear and playing safely.
Signs and Symptoms
In many cases, it is not immediately clear whether or not a spinal cord injury has occurred. Any person who may have sustained an injury to the spinal cord must be kept completely still until emergency medical personnel arrive.
Symptoms of spinal cord injury depend on the type of injury (e.g., complete, incomplete) and the location (e.g., cervical [neck], thoracic [middle back]).
Spinal cord injury may cause the following:
- Difficulty breathing
- Inability to move or to feel sensations (e.g., cold, heat, touch)
- Loss of normal bowel and bladder control (e.g., constipation, incontinence, bladder spasms)
- Numbness and weakness
- Problems maintaining balance
- Severe pain and/or pressure in the back or neck
Diagnosis
In some cases, physicians are able to assess a spinal cord injury by talking with the patient, by performing an examination, and by testing for motor and sensory ability. If the patient is unable to answer questions or symptoms indicate more severe damage, a number of diagnostic tests can be used to provide more information about the injury and its consequences.
X-rays of the spine can detect tumors, fractures, and problems with vertebrae. CT (computerized tomography) scan can provide more detail about issues that show up on x-ray. An MRI (magnetic resonance imaging) scan can help detect blood clots, herniated disks, and other issues that may be affecting the spinal cord. Myelography involves using dye to help identify damage to spinal nerves.
Other tests may be conducted within days of a spinal cord injury, including a neurological examination, which provides additional information about the severity of the injury. These tests can be used to help determine the degree of recovery that can be expected and how treatment should proceed.
In most cases, recovery depends on how patients respond to various treatment procedures and how they adapt to the changes in their lives.
Complications
Because the spinal cord is critical to so many body functions, spinal cord injury can cause a wide range of short- and long-term complications. Learning to manage these complications is an important part of the recovery process.
Complications from spinal cord injuries include the following:
- Pneumonia and asthma are common long-term complications because muscles associated with breathing usually are weakened. Breathing assistance may be necessary if the nerves to the diaphragm are damaged. Medications may be used to regulate breathing issues and patients are encouraged to get an annual flu shot.
- The heart rate can slow down considerably, or increase to an alarming level following spinal cord injury. This may cause heart problems and low blood pressure that may require intravenous blood infusions.
- Autonomic dysreflexia is a condition that occurs when a stimulus (e.g., blocked catheter, skin irritation) below the injury site triggers a message to the brain that cannot be received. This causes a reflex that constricts blood vessels and results in a reduced heart rate and high blood pressure.
- Autonomic dysreflexia increases the risk for stroke and rarely, seizures. Sometimes this condition can be resolved if the patient changes position or the stimulus is removed.
- Blood clots are of particular concern for spinal cord injury patients, as immobility reduces blood flow through the veins. Patients often are prescribed medications to prevent clotting.
- When a patient has been sitting or lying in the same position for a long time, pressure on the skin can cause the tissue to deteriorate resulting in pressure sores (also called bedsores). If feeling has been lost in certain parts of the body, the patient may not even be aware of these sores.
- Patients who develop pressure sores should change positions frequently, should take measures to maintain healthy skin, and should follow a balanced diet. Patients or caregivers also should inspect all areas of the skin carefully for cuts and sores.
- Neurogenic pain (i.e. pain that originates from nervous tissue) and burning and stinging sensations are common and may even occur in limbs that no longer have movement or feeling.
- Using other parts of the body to compensate for paralyzed limbs (e.g., using the arms to move a wheelchair) can also cause pain. Treatment includes medications, acupuncture, surgery, and spinal or brain electrical stimulation.
- Spasms are reflexes that cause uncontrolled limb movement. Spasticity is a term used to describe spasms of increased tone. These conditions occur when nerves in the spinal cord are affected by the injury and the brain and nerves can no longer communicate and control the movements.
- Medical treatments are available to help reduce spasticity. In some cases, spasms are actually beneficial, as they can improve muscle tone in the affected areas and allow some patients a little stability of the limb, which can improve mobility.
- Urinary (e.g., urinary tract infection, kidney infection) and bowel difficulties occur when the nerves controlling these functions are damaged. The brain and body can no longer coordinate and the bladder and bowel may eliminate uncontrollably. Drinking plenty of water and incorporating more fiber into the diet can sometimes help both of these problems. In some cases, catheters and medications also are used.
- Spinal cord injuries often result in sexual dysfunction and fertility problems. Typically, these problems affect men more often than women. Doctors can prescribe medication and other treatments to increase fertility.
- In many cases, spinal cord injury does not affect a woman's fertility; however, pregnancy is considered high risk and should be considered only under the care of a qualified health care provider. For both men and women, specialists can provide advice for intimacy.
- Weight loss or gain can also occur, since spinal cord injuries affect diet as well as the patient's ability to exercise. Physical therapists and nutritionists can help patients maintain healthy habits through exercise and diet.
- Depression is common in patients who have sustained a spinal cord injury. During recovery, patients often feel sadness, grief, anxiety, and stress, and a caring network of qualified health care providers, family, and friends is very important. Therapists can also help patients through this difficult time.
Treatment/Rehabilitation
Treatment for spinal cord injuries begins in the emergency room and continues long after the patient is released from the hospital. The very first procedure for treatment occurs even before the injury is diagnosed. The goals of treatment are to help the patient live the most satisfying life possible and to prevent additional injuries.
Initial Treatment
When a spinal cord injury is suspected, medical personnel immobilize the spine using rigid collars and boards. It is important to move patient as little as possible, since the level of recovery depends in part on preventing additional damage and inflammation.
Emergency room physicians take steps to stabilize blood pressure, breathing, bladder and bowel functions, and prevent blood clots. Many patients then move to the intensive care unit or a special spinal cord injury treatment center.
In some cases, the drug methylprednisolone (Medrol®) is given. While the full benefits of this medication have not been determined, it may help control damage to nerve cells if it is administered within 8 hours of the injury.
Following spinal cord injury, it is important to keep the spine still and properly aligned. In many cases, this requires using traction and a rigid neck collar. Traction involves using metal braces or a body harness to keep the skull immobile.
Surgery may be performed to remove elements that are bearing down on the spine, such as bone fragments and foreign objects. In some cases, surgery can also be used to stabilize the spine, although this procedure may be too risky at this point.
Once a neurological exam and other tests are completed and the extent of injury has been determined, a team of physicians and other specialists (e.g., social workers, physical therapists, vocational counselors, nutritionists) begin working on a long-term treatment plan.
Patients often are frightened, confused, and unsure about the future. A supportive team of qualified health care providers, family, and friends, can help the patient set achievable goals. In many cases, the greater the patient's ability to adapt, the more successful recovery will be.
Long-term Treatment
Following spinal cord injury, the first priority often is to help the patient develop as much strength as possible in the arms and legs, since these limbs are crucial for movement and communication. Patients may need to learn to use devices like walkers, wheelchairs, or leg braces, as well as devices to help them write, type, and talk on the phone.
Physical therapists work with patients to build muscle strength and occupational therapists can help patients develop skills required for day-to-day activities, such as dressing, grooming, and going to the toilet. Patients also learn how to cope with other issues, including pain and spasticity.
Vocational rehabilitation specialists can help patients determine employment options. They assess how work skills and dexterity have been affected by the injury, find job sites that complement the patient's expertise and abilities, and help secure adaptive devices. For patients who are unable to work, vocational specialists help find opportunities for meaningful projects to keep them active and build self-esteem.
Specialists also can provide recreational therapy, which helps patients participate in athletic and recreational activities. In this way, patients can get out with other people, have fun, and lead as normal a lifestyle as possible.
Modern technology also can help patients manage their treatment. For example, computers can help with a number of functions, such as communication, bathing, cleaning the house, and reading. Wheelchairs are lighter and easier for patients to work with. Some wheelchairs can go up stairs or lift a patient to eye level. Electrical stimulation devices can help patients achieve greater movement.
Prognosis
Prognosis for patients with spinal cord injuries varies and depends largely on the degree of damage. The first year following injury is critical, as more patients die of the injuries within that time period than any other. Kidney (renal) failure and pneumonia are frequent causes of death.
In many cases, physicians cannot be certain of the extent of immobility until a few months have passed since the injury. Some patients will have more mobility than others. Most function that is going to return does so within 2 years and after that, physicians usually agree that the remaining damage is permanent.
Patients often develop a number of secondary conditions following spinal cord injury. Managing these conditions through a network of qualified health care providers, therapists, family, and friends plays a large role in the patient's quality of life. Staying emotionally healthy and maintaining good eating and exercise habits are important.
There is hope for spinal cord injury patients. With technological advances, further studies on the horizon, and adaptability on the part of patient, people with spinal cord injuries are often able to do many activities that keep them independent, productive, and satisfied with their lives.
Research
Much of the current research on spinal cord injury centers on finding a way to repair an injured spinal cord. Scientists are looking at ways to slow down secondary damage or stop it completely. They are also seeking strategies for reconnecting the nerve network that connects to the spinal cord and brain, and for axon (nerve fibers that carry messages to the brain) growth. Other studies concentrate on finding ways to replace damaged nerve cells.
Researchers are examining the biochemical makeup of spinal cord cells and the cells that surround them. By understanding how cells react to each other, scientists hope to develop additional medications and procedures that will help preserve the spinal cord and keep secondary damage to a minimum.
For example, cells emit a substance called glutamate when they die. Glutamate also is released by healthy nerve cells. The overflow of glutamate that results from a spinal cord injury can cause cells to self-destruct, even healthy cells that should be preserved. Scientists are researching ways to control glutamate.
Other researchers are looking at the ways immune cells respond when a spinal cord injury occurs. While immune cells help prevent infections and clean the area of dead cells, they can also release substances that contribute to cell death. Scientists would like to find a way to stimulate the good aspects of the immune cells and control the harmful effects.
Some scientists are also exploring how mild hypothermia can help in spinal cord injuries. Cooling the body to 92 degrees Fahrenheit after injury may prevent further damage and even help recovery.
Axon regeneration is another important area of research. Successful axon networks allow for greater recovery and mobility. This is a difficult task because the area around the spinal cord needs to have more substances that encourage growth and fewer substances that restrict it.
Some medical researchers are studying how stem cells could help spinal cord injury patients. According to the Mayo Clinic, stem cells are "master cells" that can divide and eventually become new stem cells or specialized cells (e.g., heart cells, bone cells). Stem cells are the only kind of cell that can do this.
Researchers hope to find a way that spinal cord and nerve cells could be generated and transferred to the patient, much like an organ transplant. However, additional research is required.
Research to help patients with spinal cord injuries manage their lives is also ongoing. Scientists are trying to determine which rehabilitation techniques help patients most in their day-to-day lives. Additional medications and substances are being developed to control pain and spasticity and enhance sexual function. New electrical stimulation techniques may help with incontinence.
Increasing mobility is another goal of research. For example, the functional electrical stimulation (FES) system allows the patient to move immobile limbs by computer. Electrodes are placed either on the patient's limbs or inside the body through surgery, allowing the patient to move more easily and exercise more, which has a number of health benefits. However, because the movement is not very smooth, some patients have been reluctant to use the system. Researchers are looking at ways to improve this process.
Scientists are also studying how paralyzed limbs can be retrained to move. A physical therapist might help a patient simulate walking by moving legs back and forth. Or, the FES system can be utilized, using a special bicycle for pedaling.