All spines have curves, but occasionally the spine twists and develops curves in the wrong direction - sideways. It is natural for the spine to curve forward and backward to a certain degree; this is what gives the spine its "S"-like shape. However, when a person's spine twists and develops an "S" -shaped side-to-side/lateral curve, it is a condition known as scoliosis. To further explain this, think about what your spine looks and feels like if you bend forward at the waist. With most people the spine will look and feel like a straight line, but in a person with scoliosis, the spine will look and feel like a curved line.
When the patient is an adolescent, and the scoliosis does not have a known cause, the condition is called adolescent idiopathic scoliosis. This form of scoliosis occurs in an otherwise healthy child who does not have accompanying neurologic, muscular, or developmental vertebral abnormality. It is the most common form of spinal deformity seen by doctors; it has a 0.3 to 15.3 percent occurrence rate in the general population.
Most cases of scoliosis are first discovered and treated in childhood or adolescence, particularly during puberty when the curvature becomes more noticeable. Scoliosis is divided into four categories, which are based on the age the condition is diagnosed:
It is interesting to note that scoliosis appears to affect girls much more than boys. Girls are treated seven to nine percent more often. However, recent school screening studies have shown a sex ratio of nearly one to one. Therefore, it may simply be that girls seek treatment for their condition more often than the boys do. This difference in treatment paths could have an obvious link to the insecurities adolescent girls often have about appearance and body image.
If you or your child has adolescent idiopathic scoliosis, this website will offer you the following information:
As mentioned above, the normal spine naturally has some forward and backward curves. However, sideways curves are not part of the spine's normal anatomy. When the sideways curves of scoliosis appear, it is usually in the areas of the thoracic (middle) and lumbar (lower) spine. To understand how these two regions are affected, it helps to know a little about their anatomy:
The lowest part of the spine is called the lumbar spine. This area has five vertebrae. The lumbar spine's shape has what is called a lordotic curve. The lordotic shape is like a backward "C". If you think of the spine as having an "S"-like shape, the lumbar region would be the bottom of the "S". The vertebrae in the lumbar spine area are the largest of the entire spine, so the lumbar spinal canal is larger than the cervical or thoracic canals.
The thoracic spine is made up of the middle 12 vertebra of the spine. These vertebrae connect to your ribs and form part of the back wall of the thorax (the ribcage area between the neck and the diaphragm). This part of the spine has very narrow, thin intervertebral discs, so there is much less movement allowed between vertebrae than in the lumbar or cervical spine. It also has less space in the spinal canal for the nerves. The thoracic spine's curve is called kyphotic because of its shape, which is a regular "C" curve with the opening of the C in the front.
When the vertebrae (spinal bones) in these two areas of the spine curve to the side, it upsets the normal appearance and condition of the spine and its muscles. Depending on the case, scoliosis curves can occur in a variety of areas and degrees. Depending on where they are located, the curves are usually classified as: single thoracic, single lumbar, thoraco-lumbar, or double thoracic and lumbar. The curves can also range in size from as minor as 10 degrees to severe cases of more than 100 degrees. On average, curves of less than 40 degrees will be treated with conservative methods, while curves over this amount might be recommended for surgery. Generally, the only cases where surgery is considered are severe cases that lead to: continual physical pain, difficulty in breathing, significant disfigurement, or continued progression of the curve. After skeletal maturity has occurred, curves that are less than 30 degrees tend not to progress, and therefore, do not require surgery. Curves above 100 degrees are rare, but they would typically require surgery. These extreme curves can be life-threatening if the spine twists the torso so much that the heart and lung functions are compromised
Causes of Adolescent Idiopathic Scoliosis
The word "idiopathic" means that the cause of this form of scoliosis is unknown. There are many theories as to why it develops, but the root of the condition has yet to be discovered. Some of the theories are:
This is an inflammation of the gray matter of the spinal cord without the usual symptoms. The disease/condition is there, but it is not causing the problems it normally does. Therefore, it may go undetected.
Nutrition affects the body's health and the way it develops. There could be a link between poor nutrition and skeletal development, leading to scoliosis.
While this link is uncertain, scoliosis appears to run in certain families, so it may be hereditary.
Curves progress rapidly during growth spurts, perhaps showing a tie to hormonal causes. In fact, increased levels of growth hormones have been shown in girls with scoliosis in comparison to girls without it.
Structural and Biomechanical Changes
Structural and biochemical changes in the disc and muscle might be the cause. Some studies have shown increased muscular activity around the spinal curves. Leg length discrepancies have also been noted in adolescents with idiopathic scoliosis. However, there is not clear evidence that these structural and biomechanical changes are the cause of scoliosis; they may instead be a secondary result of scoliosis.
Central Nervous System Changes
Because some forms of scoliosis are associated with central nervous system disorders, a lot of research has been focused on this topic. However, such disorders have not been proven as the root of idiopathic scoliosis.
Equilibrium and Postural Mechanisms
Idiopathic scoliosis could be related to the way a person's body is carried. If a child has problems with posture, balance, and body symmetry, it could affect the way the spine is positioned. If the problems are chronic, it could disrupt the way the spine and muscles develop.
Likelihood of Progression
Once scoliosis is diagnosed, there is always the question of whether or not the curves will continue to progress and grow in size/degrees. While there is no sure-fire way to tell if a curve will progress, we do know the following:
In many cases of adolescent scoliosis, the child will not even notice the problem. Though the spine may curve sideways, in minor cases the curves are not obvious unless the patient is bending over so that the spine protrudes. Currently, many schools screen young students for scoliosis, so referrals often come from school health workers. Parents or physical education instructors are also frequently the first to notice signs of scoliosis in a child.
Because the majority of scoliosis patients do not suffer any physical pain from the disorder, it often is not discovered until the curves have progressed to a more obvious state. In fact, if the child is suffering back pain, the diagnosis is less likely to be scoliosis.
The following are a few typical physical features/symptoms of scoliosis:
If scoliosis is suspected in an adolescent, a physician must diagnose it before an appropriate treatment plan can be developed.
In order to make a proper diagnosis and rule out other possible conditions, the child's history is taken. The physician will ask about the following:
The doctor will have the patient bend over to make the curve evident.
This is an observation of the three-dimensional characteristics of the spine. The kyphosis is the forward curve (thoracic spine). Lordosis is the backward curve (cervical and lumbar spine). Scoliosis would bring about a sideways curve.
This will be done to test the nerves and their level of functioning.
The following tests might be ordered to determine if scoliosis exists in the spine. Any abnormal anatomical findings will help rule out idiopathic scoliosis. Because the condition is idiopathic, the cause cannot be determined.
X-rays are a painless way of using radioactive materials to capture images of bone. They are a photograph that is taken using X-rays - electromagnetic waves. During X-rays, you will be asked to hold certain positions while standing or lying on a table, and you will need to hold very still while pictures are taken of your spine. With scoliosis the following images will be taken:
The spine's curve will be measured by the Cobb technique. This means that the ends of each vertebra in the curve are determined and a line is drawn along the endplate of each of them, making a connected perpendicular/vertical line. This line makes up the angle of the curve, which can be measured in degrees.
MRI Scan (Magnetic Resonance Imaging)
This radiographic study does not use radiation. By using magnetic and radio waves, the MRI creates computer-generated images. The MRI is able to cut through multiple layers of the spine and show any abnormality of soft tissues, such as nerves and ligaments. With an MRI, the patient lays on a table that slides into a machine with a large, round tunnel. The machine's scanner then takes many pictures that are watched and monitored by a technician. There are also some new MRI machines called Open MRIs that might be more comfortable for patients who experience claustrophobia. The procedure takes 30-60 minutes.
The MRI allows the doctor to look for any left thoracic curves, in order to rule out Arnold-Chiari malformation or Syringomyelia - a disorder of the spinal cord. In addition, abnormalities that are sign's of a hereditary disorder can be looked for in order to rule out congenital scoliosis.
The treatment chosen for an adolescent with idiopathic scoliosis will vary depending upon the severity of the curve, the age of the patient, and by how far along the child is in skeletal maturity.
The following are some possible treatment options:
On the surface, exercise may seem like a good way to help scoliosis, but it actually has not been shown to offer any benefit in the improvement of the disorder. However, exercise might be useful in decreasing or controlling any pain that might be present.
Electrospinal stimulation: The electrical stimulation of muscles is relatively painless and has good patient acceptance. However, this treatment has not proven to be a very effective treatment, particularly with curves greater than 30 degrees.
Bracing: With curves between 30-40 degrees, bracing is generally considered, particularly if the patient is still growing and the curve is likely to increase in size. If a brace is suggested, it is important that the patient wear the brace daily for the number of hours prescribed by the doctor. Sometimes an adolescent might feel self-conscious about wearing a brace. It is a time of life when anything out of the ordinary can be viewed as embarrassing or shameful. Though the brace can help the curve from getting worse, know that it may take some time for you or your child to get used to wearing it. Adults tend to be less worried about what their peers think, but adolescence is a time when appearance is often of great concern. Listen to your child's concerns and help them find ways to feel better about their appearance.
Scoliosis is a curvature to the spine that often affects more than one area of the spine. Thus, a brace can be used to support all the curved areas that need to be protected from progression. These are the three most common braces:
The Milwaukee brace can correct any kind of spinal curve. It uses two metal struts/bars that extend from the chin to the torso, corrective pads, and a neck ring. The brace exerts pressure to the spine, pushing it into a straighter position. It is an effective brace, but it has to be worn nearly the entire day, and many adolescents find it very embarrassing to wear.
The Boston brace is a plastic body jacket that hugs the body and puts pressure on the ribs and back. The pressure pushes the spine into a straighter position.
Thoracolumbosacral orthosis is a fancy way of describing a brace that supports several parts of the spine: the cervical (upper/neck), the thoracic (middle), the lumbar (lower), and the sacrum (base of the spine). If the brace also supports the cervical spine (upper/neck), it is called a Cervicothoracolumbosacral orthosis. This brace is an underarm brace that fits around the torso, hips, and under the arms. This brace is less cumbersome than the others and can be worn for just 16 hours a day - leaving time during the day for the patient to be brace free. However, this brace is not suitable for all types of curves. It depends upon the location and severity of the curves.
Monitoring: If the patient's curve is minor, meaning in the 15-20 degree range, the doctor will likely choose monitoring the curve rather than bracing it. With monitoring, the patient will have X-rays taken every year, or every four months in rapid growth years.
Surgery: If a curve is 50 degrees or higher, surgery is generally considered. The surgery of choice for scoliosis is a spinal fusion with instrumentation. This means the vertebra (spinal bones) in the curved areas will be fused together to make one long bone. It will be straightened with the use of rods and wires attached to the bones.
X-rays will be taken of the patient in a bending position to help assess spinal flexibility and the way the spine is constructed. This will help determine the proper surgical technique for each individual case. The surgeon may use a posterior-only approach, which involves going into the spine through the back. An anterior/posterior approach may be used instead, which is both a front and back approach. The choice of technique depends upon: the flexibility of the spine, the location and degree of the curve, and whether there is any nerve-root compression.
Nearly all surgeries will use some type of pedicle screws and rods in order to help straighten the spine. The screws attach to the vertebra's pedicles. (The pedicles are the bony projections that connect to both sides of the vertebra's laminae, which extend from the vertebral body to cover the spinal canal. The spinal canal is the hole in the center of the vertebrae.) The rods then connect the screws together. When they are all pulled together, they bring the curve into its proper position.
The following is a brief description of each surgery:
This approach involves correcting the curve by going into the chest through the front of the body. It is used most often for curve correction and lumbosacral fusion (a fusion of the area at the end of the lumbar/lower spine and sacrum/base of the spine in order to give extra support and secure the vertebrae). The anterior approach to surgery is limited to the area between the fifth lumbar vertebra and the ninth thoracic vertebra. If the curve needs correcting elsewhere, a different approach will be used.
To give you a general idea of what is done during surgery for scoliosis, here is a basic overview of anterior instrumentation surgery:
This approach is through the back. This surgery is similar to the anterior approach involving the use of pedicle screws and spinal fusion. However, it generally takes longer for the fusion to occur and it involves more vertebrae. This approach may, or may not, involve fusion.
The posterior approach could include segmental instrumentation, where hardware is used on each individual vertebra in a segment of the curve in order to straighten it. This approach could include the following instrumentation:
Sublaminar wires - This is an older technique that is not often used.
Harrington rods - This type of hardware fixation is rarely used anymore. In the past, the more flexible Harrington rods were very popular, but now materials that are more rigid are used in surgery. Harrington rods have also been associated with an increased risk of developing "flat-back" (loss of curve in the lumbar spine).
Multi-level hooks and pedicle screws - This approach involves several points of hardware fixation to the spine with the use of hooks, rods, and pedicle screws. This technique allows for complex curve correction, fewer segments of the spine having to be immobilized, and preservation of the lumbar spine's curve. The disadvantages are that it takes more time and manipulation during surgery than other posterior techniques.
Cotrel-Dubousset Instrumentation (CDI) - This approach uses flexible rods and pedicle screws. If there is only one thoracic curve, this method is most often used. It can also be used with lumbar curves in order to restore the lordosis curve. However, because the rods are not rigid, this approach is not appropriate for all cases of scoliosis surgery.
Combined Anterior/Posterior Approach
This approach obviously involves both a front and back approach. The down side to this surgery is that it puts a lot of trauma on the muscles so the patient has a longer hospital stay.
Possible Complications/Problems with Surgery
With any surgery, there is a risk of complications. When surgery is done near the spine and spinal cord these complications (if they occur) can be very serious. Complications could involve subsequent pain and impairment and the need for additional surgery. You should discuss the complications associated with surgery with your doctor before surgery. The list of complications provided here is not intended to be a complete list of complications and is not a substitute for discussing the risks of surgery with your doctor. Only your doctor can evaluate your condition and inform you of the risks of any medical treatment he or she may recommend.
Any time surgery is performed, there is a risk of infection. The infection can be only in the skin incision or it can spread deeper to involve the areas around the spinal cord and the vertebrae. A wound infection that involves only the skin incision is considered a "superficial" infection. It is less serious and easier to treat than the deeper infection. Surgeons take every precaution to prevent infections. To reduce the risk of infection, you will probably be given antibiotics right before surgery - especially if bone graft, metal screws, or plates will be used for your surgery.
Infections occur in less than 1% of spinal surgeries. If the surgical wound becomes red, hot, and swollen and does not heal, it may be infected. Infections will usually cause increasing pain. You may run a fever and have shaking chills. The wound may ooze clear liquid or yellow pus. The wound drainage may smell bad.
Contact your doctor immediately so the wound can be treated and antibiotic medication can be prescribed if necessary. The superficial wound infection can usually be treated with antibiotics, and perhaps removing the skin stitches. The deeper wound infections can be very serious and will probably require additional operations to drain the infection. In the worst cases, any bone graft, metal screws, and plates that were used may need to be removed.
In many different types of spinal operations, metal screws, plates, and rods are used as part of the procedure to hold the vertebrae in alignment while the surgery heals. These metal devices are called "hardware". Once the bone heals, the hardware is usually not doing much of anything. Sometimes before the surgery is completely healed, the hardware can either break or move from the correct position. If this occurs, it may require a second operation to either remove or replace the hardware.
The term "pseudo" means false and "arthrosis" refers to joint. The term "pseudoarthrosis" then means false joint. A surgeon uses this term to describe either a fractured bone that has not healed or an attempted fusion that has not been successful. A pseudoarthrosis usually means that there is motion between the two bones that should be healed, or fused, together. When the vertebrae involved in a surgical fusion do not heal and fuse together, there is usually continued pain. The pain may actually increase over time. The spinal motion can also stress the metal hardware used to hold the fusion. The screws and rods may break. A pseudoarthrosis may require more surgery to try to get the bones to heal. Your surgeon may add more bone graft, replace the metal hardware, or add an electrical stimulator to try to get the fusion to heal.
Any time you operate on the spine, there is some risk of injuring the spinal cord, which can lead to nerve damage. The nerves in each area of the spinal cord connect to specific parts of your body. This is why damage to the spinal cord can cause paralysis in certain areas and not others; it depends on which spinal nerves are affected.
Some spinal operations are simply unsuccessful. One of the most common complications of spinal surgery is that it does not get rid of all of your pain. In some cases, it may be possible to actually increase your pain. Be aware of this risk before surgery and discuss it at length with your surgeon. He or she will be able to give you some idea of the chance that you will not get the relief that you expect. Some pain after surgery is expected. However, if you experience chronic pain well after the operation, you should let your doctor know.
The spinal cord and spinal nerves carry the nerve signals that allow the rest of your body to function, feel sensation - and even have sex. Damage to the spinal cord and the nerves around the spinal cord can cause many problems. If a nerve is damaged that connects to the pelvic region, it could cause sexual dysfunction.
Problems with Leaving Large Curves Untreated
As there are obviously some considerable risks to surgery, a patient who has been recommended for surgery may opt not to undergo an operation. In these cases, what are the risks of leaving large curves untreated?
Increased Back Pain
Patients with untreated large curves have higher rates of daily back pain than the average person.
Reduced Respiratory Function
Large curves lead to deformities that can lower the space for the body's vital organs, such as the lungs and heart. The reduction in space can compromise the patient's ability to breathe and for his/her heart to function properly. In curves of 100 degrees or more, the affects can be life threatening.
Because we live in a society that is very concerned about body image, deformities, such as large curves in the back, can cause sufferers to a develop a poor self image. It has also been shown that people who suffer from serious scoliosis curves have higher unemployment rates and disability pensions, as well as lower marriage rates. The latter result is likely due to negative self-image.
Progression of Neurologic Disorders
Scoliosis results in misaligned vertebrae, which in turn can lead to nerves being pressured and damaged. This can lead to a loss in motor functions, numbness, and pain.
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