Spinal cord injury
What is it?
If you've recently experienced a spinal cord injury, it might seem like every aspect of your life will be affected by this injury. A spinal cord injury often causes permanent disability or loss of movement (paralysis) and sensation below the site of the injury.
Many scientists are optimistic that advances in research will someday make the repair of spinal cord injuries an attainable goal. In the meantime, treatments and rehabilitation allow many people with a spinal cord injury to lead productive, independent lives.
Your ability to control your limbs after spinal cord injury depends on two factors: the neurological level of the injury and the completeness of injury. The lowest normally functioning segment of your spinal cord is referred to as the neurological level of your injury. The completeness of the injury is classified as either:
- Complete. If all sensory (feeling) and motor function (ability to control movement) is lost below the neurological level, your injury is called complete.
- Incomplete. If you have some motor or sensory function below the affected area, your injury is called incomplete.
Additionally, paralysis from a spinal cord injury may be referred to as:
- Tetraplegia or quadriplegia. This means your arms, trunk, legs and pelvic organs are all affected by your spinal cord injury.
- Paraplegia. This paralysis affects all or part of the trunk, legs and pelvic organs.
Your health care team will perform a series of tests to determine the neurological level and completeness of your injury.
Spinal cord injuries of any kind may result in one or more of the following signs and symptoms:
- Loss of movement
- Loss of sensation, including the ability to feel heat, cold and touch
- Loss of bowel or bladder control
- Exaggerated reflex activities or spasms
- Changes in sexual function, sexual sensitivity and fertility
- Pain or an intense stinging sensation caused by damage to the nerve fibers in your spinal cord
- Difficulty breathing, coughing or clearing secretions from your lungs
Emergency signs and symptoms
Emergency signs and symptoms of spinal cord injury after an accident may include:
- Extreme back pain or pressure in your neck, head or back
- Weakness, incoordination or paralysis in any part of your body
- Numbness, tingling or loss of sensation in your hands, fingers, feet or toes
- Loss of bladder or bowel control
- Difficulty with balance and walking
- Impaired breathing after injury
- An oddly positioned or twisted neck or back
Your brain and central nervous system
The central nervous system consists of the brain and spinal cord. The spinal cord extends downward from the base of your brain and is made up of nerve cells and groups of nerves called tracts, which go to different parts of your body. The lower end of your spinal cord stops a little above your waist in the region called the conus medullaris. Below this region is a group of nerve roots called the cauda equina. Tracts in your spinal cord carry messages between the brain and the rest of the body. Motor tracts carry signals from the brain to control muscle movement. Sensory tracts carry signals from body parts to the brain relating to heat, cold, pressure, pain and the position of your limbs.
Injury may be traumatic or nontraumatic
A traumatic spinal cord injury may stem from a sudden, traumatic blow to your spine that fractures, dislocates, crushes or compresses one or more of your vertebrae. It may also result from a gunshot or knife wound that penetrates and cuts your spinal cord. Additional damage usually occurs over days or weeks because of bleeding, swelling, inflammation and fluid accumulation in and around your spinal cord.
A nontraumatic spinal cord injury may be caused by arthritis, cancer, inflammation or infections, or disk degeneration of the spine.
Damage to nerve fibers
Whether the cause is traumatic or nontraumatic, the damage affects the nerve fibers passing through the injured area and may impair part or all of your corresponding muscles and nerves below the injury site. A chest (thoracic) or lower back (lumbar) injury can affect your chest, abdomen, legs, bowel and bladder control, and sexual function. In addition, a neck (cervical) injury affects movements of your arms and, possibly, your ability to breathe.
Common causes of spinal cord injury
The most common causes of spinal cord injuries in the United States are:
- Motor vehicle accidents. Auto and motorcycle accidents are the leading cause of spinal cord injuries, accounting for more than 40 percent of new spinal cord injuries each year.
- Acts of violence. As many as 15 percent of spinal cord injuries result from violent encounters, often involving gunshot and knife wounds, according to the National Institute of Neurological Disorders and Stroke.
- Falls. Spinal cord injury after age 65 is most often caused by a fall. Overall, falls cause about one-quarter of spinal cord injuries.
- Sports and recreation injuries. Athletic activities, such as impact sports and diving in shallow water, cause about 8 percent of spinal cord injuries.
- Alcohol. Alcohol use is a factor in about 1 out of every 4 spinal cord injuries.
- Diseases. Cancer, arthritis, osteoporosis and inflammation of the spinal cord also can cause spinal cord injuries.
Although a spinal cord injury is usually the result of an unexpected accident that can happen to anyone, certain factors may predispose you to a higher risk of sustaining a spinal cord injuring, including:
- Being a man. Spinal cord injuries affect a disproportionate amount of men. In fact, women account for only about 20 percent of spinal cord injuries.
- Being between the ages of 16 to 30. You're most likely to suffer a spinal cord injury if you're between the ages 16 and 30. Motor vehicle crashes are the leading cause of spinal cord injuries for people under 65, while falls cause most injuries in older adults.
- Being active in certain sports. While being active is one of the best things you can do for your overall health, it may place you at greater risk of a spinal cord injury. Athletic activities that may increase your risk of a spinal cord injury include football, rugby, wrestling, gymnastics, horseback riding, diving, surfing, roller-skating, in-line skating, ice hockey, downhill skiing and snowboarding.
- Having an underlying bone or joint disorder. A relatively minor injury can cause a spinal cord injury if you have another disorder that affects your bones or joints, such as arthritis or osteoporosis.
At first, changes in the way your body functions may be overwhelming. However, you can learn new skills and ways to adapt old skills to deal with the physical effects of a spinal cord injury. Possible difficulties you may encounter include:
- Bladder control. Your bladder will continue to store urine from your kidneys. However, your brain may no longer be able to control bladder emptying, as the message carrier (the spinal cord) has been injured. The loss of bladder control increases your risk of urinary tract infections. It may also cause kidney infection and kidney or bladder stones. Drinking plenty of clear fluids may help. And during rehabilitation, you'll learn new techniques to empty your bladder.
- Bowel control. Although your stomach and intestines work much like they did before your injury, your brain may no longer be able to control the muscles that open and close your anus. This may cause fecal incontinence. A high-fiber diet may help regulate your bowels, and you'll learn techniques to better control your bowels during rehabilitation.
- Impaired skin sensation. Below the neurological level of your injury, you may have lost part or all skin sensations. Therefore, your skin can't send a message to your brain when it's injured by things such as prolonged pressure, heat or cold. This can make you more susceptible to pressure sores, but changing positions frequently — with help, if needed — can help prevent these sores. And, you'll learn proper skin care during rehabilitation, which can help you avoid these problems.
- Circulatory control. A spinal cord injury may cause circulatory problems ranging from spinal shock immediately following your spinal cord injury to low blood pressure when you rise (orthostatic hypotension) to swelling of your extremities throughout your lifetime. These circulation changes may increase your risk of developing blood clots, such as deep vein thrombosis or a pulmonary embolus. Another problem with circulatory control is a potentially life-threatening rise in blood pressure (autonomic hyperreflexia). Your rehabilitation team will teach you how to prevent autonomic hyperreflexia.
- Respiratory system. Your injury may make it more difficult to breathe and cough if your abdominal and chest muscles are affected. These include the diaphragm and the muscles in your chest wall and abdomen. Your neurological level of injury will determine what kind of breathing problems you may have. If you have cervical and thoracic spinal cord injury you may have an increased risk of pneumonia or other lung problems. Medications and therapy can treat these problems.
- Muscle tone. Some people with spinal cord injuries may experience one of two types of muscle tone problems: spastic muscles or flaccid muscles. Spasticity can cause uncontrolled tightening or motion in the muscles. Flaccid muscles are soft and limp, lacking muscle tone.
- Fitness and wellness. Weight loss and muscle atrophy are common soon after a spinal cord injury. However, limited mobility after spinal cord injury may lead to a more sedentary lifestyle, placing you at risk of obesity, cardiovascular disease and diabetes. A dietitian can assist you in attaining a nutritious diet to sustain an adequate weight. Physical and occupational therapists can help you develop a fitness and exercise program.
- Sexual health. Sexuality, fertility and sexual function may be affected by spinal cord injury. Men may notice changes in erection and ejaculation; women may notice changes in lubrication. A spinal cord injury may cause decreased or absent sensation and movement below the level of injury, but a person may notice a heightened sensitivity in areas above the level of injury. Doctors, urologists and fertility specialists who specialise in spinal cord injury can offer options for sexual functioning and fertility. There's usually no physical change in women with a spinal cord injury that inhibits sexual intercourse or pregnancy. Most women with a spinal cord injury can experience labour, have a normal delivery and breast-feed.
- Pain. Some people may experience pain, such as muscle or joint pain from overuse of particular muscle groups. Nerve pain, also known as neuropathic or central pain, can occur after a spinal cord injury, especially in someone with an incomplete injury.
In the emergency room, a doctor may be able to rule out a spinal cord injury by careful inspection, testing for sensory function and movement, and asking some questions about the accident. But if the injured person complains of neck pain, isn't fully awake, or has obvious signs of weakness or neurological injury, emergency diagnostic tests may be needed.
These tests may include:
- X-rays. Medical personnel typically order these tests on all people who are suspected of having a spinal cord injury after trauma. X-rays can reveal vertebral (spinal column) problems, tumours, fractures or degenerative changes in the spine.
- Computerized tomography (CT) scan. A CT scan may provide a better look at abnormalities seen on an X-ray. This scan uses computers to form a series of cross-sectional images that can define bone, disk and other problems.
- Magnetic resonance imaging (MRI). MRI uses a strong magnetic field and radio waves to produce computer-generated images. This test is extremely helpful for looking at the spinal cord and identifying herniated disks, blood clots or other masses that may be compressing the spinal cord.
- Myelography. Myelography allows your doctor to visualize your spinal nerves more clearly. After a special dye is injected into your spinal canal, X-rays or CT scans of your vertebrae can suggest a herniated disk or other lesions. This test is used when MRI isn't possible or when it may yield important additional information that isn't provided by other tests.
If your doctor suspects a spinal cord injury, he or she may prescribe traction to immobilize your spine.
A few days after injury, when some of the swelling may have subsided, your doctor will conduct a neurological exam to determine the level and completeness of your injury. This involves testing your muscle strength and your ability to sense light touch and a pinprick.