Everyone’s spine has natural curves. These curves round our shoulders and make the lower back curve slightly inward. But some people have spines that also curve from side to side, a common condition called scoliosis. On an X-ray, a spine with scoliosis looks more like an “S” or a “C” than a straight line. Some of the bones in a scoliotic spine also may have rotated slightly, making the person’s waist or shoulders appear uneven.
Scoliosis affects about 2 percent of the population, including children and adults, and tends to run in families. If someone in a family has scoliosis, the likelihood of another family member having it is much higher – about 20 percent.
As the population ages, adult degenerative scoliosis is becoming more common, with the condition typically developing at between age 50 to 70. The condition can have devastating effects on a person’s life in later years. Treatment in this older population presents particular changels due to other back conditions, such as osteoporosis. But significant advances – including minimally invasive surgery, new neuro-monitoring techniques and 3-dimensional imaging – allows older patients to receive limited doses of anesthesia and benefit from quicker recovery.
Scoliosis is defined as curvature of the spine greater than 10 degrees, as measured on an X-ray. Anything less is simply due to normal variation.
Scoliosis may be divided into five types:
Congenital Scoliosis– Congenital means that a person is “born with” scoliosis. Congenital scoliosis is caused by an abnormality of one or more vertebrae where they fail to form properly. This can be seen on X-ray and directly in the operating room.
Idiopathic Scoliosis– This is the most common form of scoliosis. The name idiopathic means “the cause is unknown.” Those with this type of scoliosis are otherwise healthy and normal. The spine shows no abnormality of the bones themselves on X-rays or by looking at it directly in the operating room. While the overall incidence is equal in females and males, progressive or severe idiopathic scoliosis is about six to seven times more frequent in females.
Neuromuscular Scoliosis– This type of scoliosis occurs in people who have a disease of the nervous system, such as cerebral palsy.
Postural Scoliosis– Also known as “hysterical scoliosis,” postural scoliosis may be a result of pain, as a patient tilts to relieve the pain. It can be reversed by relieving the pain or by having the patient lie flat. X-rays don’t show any abnormality of the vertebrae.
Syndromic Scoliosis– This type of scoliosis occurs in people with a syndrome, such as Marfan syndrome or one of the skeletal dysplasias such as achondroplasia.
Progressive, severe scoliosis can produce three major problems:
If the part of the spine in the chest, called the thoracic spine, curves more than 60 degrees, the volume of the chest can be reduced, potentially compromising the function of the heart and lungs. For example, the heart may have to work harder to pump the normal volume of blood or the affected individual may have shortness of breath.
Severe curvature of the lower half of the spine that connects the chest with the pelvis, known as the lumbar spine, may push the contents of the abdomen against the chest and interfere indirectly with heart and lung function. Curvature of the lumbar spine also may alter sitting balance and posture.
Severe curvature of either the thoracic (upper) or the lumbar (lower) spine, or both, eventually becomes visible to others. The resulting tilting and twisting of the back, shoulders and pelvis may produce an appearance that the individual finds unacceptable. If idiopathic scoliosis affects a girl around the time of puberty, when body image is developing hand-in-hand with self-esteem, the condition can pose significant psychological and emotional challenges.
Idiopathic scoliosis may also involve pain, which is more common in adults with scoliosis.
Uneven ribs and shoulders may be the first noticeable signs of scoliosis. The diagnosis is based upon an X-ray of the spine.
Other tests may be necessary if an underlying disease is suspected as the cause of scoliosis. Symptoms of a possible underlying disease include:
Deformities of the foot, such as an abnormally high arch that could cause imbalance.
Discolored skin spots or pigmented birthmarks that could be a sign of neurofibromatosis, a genetically inherited disease in which nerve tissue grows tumors. Neurofibromas may be harmless or may cause skeletal or neurological problems, including pressure on spinal nerves.
Significant pain, which typically is not a symptom of scoliosis. Patients who tilt to relieve pain can develop scoliosis.
Certain types of scoliosis are associated with other diseases, such as kidney disease. If an underlying disease is suspected, additional tests – such as an ultrasound to look for kidney disease and a magnetic resonance imaging (MRI) scan to look for a possible neurological disorder – may be performed.
Scoliosis treatment is based on the degree of curvature of the spine, viewed from the front or back by X-ray. The following are general guidelines for treatment.
Less Than 10 Degrees
This is not scoliosis. Scoliosis is defined as spinal curvature greater than 10 degrees. Curvature under 10 degrees is considered a normal variation, just as there is a normal range for weight and for height.
10 Degrees to 30 Degrees
In this range, scoliosis is observed to see if it progresses.
30 Degrees to 50 Degrees
In this range, bracing is the standard of care in the United States. The scoliosis brace is known as a TLSO, which stands for thoraco-lumbar spinal orthotic. The idea behind bracing is to stop or slow progression of the curve so that it stays under 50 degrees. The two principal types of braces used are the Milwaukee brace, developed by Dr. Walter Blount of Milwaukee, and the Boston brace, developed by Dr. John Hall of Boston. Brace treatment successfully stops curve progression in about 80 percent of children.
More Than 50 Degrees
Beyond 50 degrees, the spine loses its ability to compensate and progression becomes inevitable even after the child is mature. The only way to stop progression at this stage is a surgery called spinal fusion. Think of the vertebrae as beads on a string. The spine bends between the vertebrae as a string bends between the beads, causing the beads to move. The way to stop the beads from moving is to stick them together. Spinal fusion surgery joins the vertebrae.
There is no clear evidence that untreated scoliosis or scoliosis treated with bracing or spinal fusion will increase the risk of back pain or arthritis in the long term. The younger a child is when diagnosed with scoliosis – or the more the child has to grow – the greater the risk of scoliosis progressing.
After puberty, curves under 50 degrees are not likely to get worse. For this reason, the goal of scoliosis mangement is to keep curves under 50 degrees until the child has matured. Children with curves under 50 degrees typically grow up into adults with no significant problems related to scoliosis.
Medication, Physical Therapy
In most cases, treatment for adults begins with a combination of non-surgical treatments administered from several weeks to months. These include:
Anti-inflammatories, such as ibuprofen and mild narcotics to relieve pain
Epidural steroid injections to relieve leg pain
Physical therapy to stablize the spine
Minimally Invasive Surgery
UCSF Medical Center is one of the few medical centers in Northern California to offer advanced minimally invasive spinal fusion surgery. These include XLIF (eXtreme Lasteral Interbody Fusion) or DLIF (Direct Lateral Interbody Fusion) procedures that limit the dose of anesthesia and effectively restore quality of life.
During these procedures, a surgeon creates a small portal in a patient’s side, between the ribs and hip, minimizing muscle stripping while allowing access to the spine. The procedures enable surgeons to correct the side-to-side curvature of the spine and restore spinal balance or alignment so the spine is not pitched forward.
A potential complication of spine surgery is damage to the nerves running along the psoas muscle, one of the body’s major muscles responsible for stabilizing the base of the spine and allowing the spine to flex and rotate the hip joint. To limit potential nerve injuries, doctors at UCSF Medical Center use neuromonitoring during spine surgery, which allows surgeons to stimulate and test nerves during surgery.
Our doctors also use 3-dimensional imaging techniques during surgery to see the spine more clearly, increase accuracy when placing spinal instruments and improve patient safety.
Treatment for Children
Most spine curves in children with scoliosis will remain small and need only to be watched by an orthopedist for any sign of progression. If a curve does progress, an orthopedic brace can be used to prevent it from getting worse. Children undergoing treatment with orthopedic braces can continue to participate in a full range of physical and social activities.
If the curve of the spine is severe when first seen, or if treatment with a brace does not control the curve, surgery may be necessary.