Idiopathic Scoliosis

1. Overview
2. Evaluation/Diagnosis of Scoliosis
3. Non-Surgical Treatment
4. Surgical Treatment
5. Recovery and Outcomes
6. The Scoliosis Service at HSS
7. Frequently Asked Questions and Answers

Overview

Idiopathic scoliosis is a condition in which the spine is curved in one or more places with a lateral (or sideways) orientation. This type of curve is distinguished from that which has a forward orientation and appears as a hump, a condition known as kyphosis. The term idiopathic means that there is no known cause for the condition.

Anteroposterior (AP) view of the spine (standing) demonstrates scoliotic curve of the thoracic spine and lumbar spine.	Lateral view of the spine (standing) demonstrates increased kyphotic curvature of the thoracic spine.

Orthopaedic Surgeons further define idiopathic scoliosis by the age of the patient. These categories include:

• Infantile idiopathic scoliosis: affecting children from 0 to 3 years of age. This is a rare condition that occurs equally in boys and girls. Although this diagnostic category begins with birth, idiopathic scoliosis does not usually come to the attention of the pediatrician and orthopaedist until the child is about 6 months old and is beginning to sit up unassisted. A leaning posture while seated may be the first sign of the condition.
  
  
• Juvenile idiopathic scoliosis: affecting those from 4 to the onset of puberty with a preponderance of cases occurring in girls.
  
  
• Adolescent idiopathic scoliosis: affecting young people from puberty to maturity. This is the age group with the greatest number of new diagnoses. In contrast to infantile idiopathic scoliosis, the condition is predominantly seen in girls.
  
  
• Adult idiopathic scoliosis: affecting patients who have reached maturity. Many cases diagnosed in adulthood are thought to have been present during adolescence.
  
  
• De novo scoliosis: Some new cases in older patients are associated with changes resulting from osteoporosis (a condition in which bone density decreases and the bones become more fragile and likely to break on impact.). Degenerative changes (Arthritis) of the spine may also lead to scoliosis.
  
  

The course of treatment for patients in these different age groups varies considerably and depends on a variety of factors including the extent of the curve at the time of diagnosis and during follow-up, the patient’s stage of bone growth, the amount of pain and deformity associated with the condition, and the patient’s willingness and ability to withstand surgery should it be deemed necessary.

For all patients with scoliosis, however, the goal of treatment is the same: to alleviate symptoms and to stop the curve from progressing. Aesthetic considerations also play a role, particularly for adolescents and young adults.

Evaluation/Diagnosis of Scoliosis

A certain amount of lateral curvature in the spine is normal. Orthopaedists measure this curve by degrees and do not diagnose scoliosis unless the curve exceeds 10 degrees. In fact, because it does not cause troublesome symptoms when the curve is minimal, many mild cases of scoliosis may go undetected.

For those patients who do seek medical attention, the orthopaedist begins the evaluation by assessing appearance and flexibility. X-ray images also offer important information and help the orthopaedist pinpoint the exact site or sites of the curve. They also show whether there are abnormalities in the spine that are associated with Congenital Scoliosis.

Two types of curve may be present: the first curve to appear in the spine (the primary curve) and the compensatory curve that the patient develops in effort to maintain an erect posture. Neurological evaluation is also part of the initial assessment since scoliosis can have a neuromuscular cause (these are non-idiopathic cases), or the curve may be causing neurological symptoms.

When the curve has been measured and found to exceed 10 degrees, and no underlying cause for the condition can be identified, the patient is diagnosed with idiopathic scoliosis.

It’s interesting to note that idiopathic scoliosis is found all over the world and that incidence is equal among various ethnic groups. More individuals are treated in the United States than in many countries, owing to our more aggressive medical approach to the condition and the emphasis we place on appearance.

Non-Surgical Treatment

While age is certainly not the only consideration involved, the age-based diagnostic categories of idiopathic scoliosis may provide the easiest key to understanding non-surgical treatment.

Infantile idiopathic scoliosis: For many families in which a child has been diagnosed with infantile idiopathic scoliosis, the news is good. About 80% of all cases resolve on their own. For all young children with a curve that is less than 30 degrees, the orthopaedist will observe the patient and examine him or her at regular intervals.

If the curve continues to progress, the infant or toddler will be fitted with a brace. These external devices are designed to slow or arrest the progression of the curve. Unfortunately, they can not correct the problem. Moreover, use of braces can be difficult in these patients due to their small size-it’s harder for the orthopaedist to achieve the correct alignment with the brace. The discomfort and restriction of wearing a brace also presents a challenge for patient and parent.

For these children, the goal of non-surgical treatment is to control the curve so that surgical treatment does not become necessary until the child has achieved most, if not all, of his or her growth.

Juvenile idiopathic scoliosis: As with younger patients, observation, followed by the use of a brace if the curve progresses, are the only available non-surgical treatment. Braces work to arrest the curve permanently in about 60% of juvenile patients, and no further treatment is needed. In the remaining group of patients, as with cases of infantile idiopathic scoliosis, the goal is to control the curve well enough so that surgery can be delayed until after the adolescent growth spurt has been reached. Unfortunately, complications of scoliosis can occur that mandate the need for surgery before that time. These include pulmonary compromise, in which the curvature of the spine prevents the lungs from fully forming and functioning normally. As a result, heart disease may also develop.

Adolescent idiopathic scoliosis: Patients whose curves remain stable undergo regular physical examinations to confirm their status. Use of a brace is initiated for progressive curves. The result of this treatment is quite good with 75-80% of curves controlled in this fashion. If the curve can be controlled at less than 40 degrees, the patient may never require additional treatment. However, if the curve reaches 50 degrees, it can be expected to worsen, even after full growth is achieved, and to eventually require surgical treatment.

Adult idiopathic scoliosis: Non-surgical treatment for adult patients is generally based on symptoms. For patients experiencing pain and restrictions on mobility, pain medication and physical therapy are prescribed. The use of braces offers little benefit, and is reserved for short term pain relief in a minority of patients. As with younger patients, the decision to proceed to surgical treatment is guided by progression of the curve and related symptoms.

Surgical Treatment

Historically, the primary surgical treatment for scoliosis was to fuse those areas of the spine in which the curve was developing. In essence, this process welds the vertebrae together preventing both progression of the curve and additional growth of the spine. This surgery was followed by a long recovery period in a cast. Today, surgery for scoliosis is more sophisticated and combines the fusing procedure with instrumentation, the placement of hooks, screws and rods that hold the spine in correct alignment. This procedure may require more than one operation as the surgeon may need to approach the site from different angles. For younger patients alternatives are available that help preserve growth. With the use of instrumentation, recovery is also significantly shortened.

Infantile and juvenile idiopathic scoliosis: Should surgery become necessary for these youngest patients, the orthopaedist often recommends the use of "growing rods." This technique involves placing what is, in essence, an internal brace to hold the spine in proper alignment, and then adjusting these instruments periodically to correct the curve and to accommodate the growing spine. This is often considered preferable to proceeding to definitive treatment-the fusing and instrumentation previously described-since it offers the patient the best chance to achieve normal growth and height.

The drawback to this technique is that it requires multiple operations, the first to implant the devices, and subsequent ones to adjust the rods. These surgeries are needed about every six months-whenever the curve is seen to progress-and continue until the patient has reached puberty or enters a period of growth spurt, or patient and physician decide to go on to a final, definitive surgical treatment. Complications can occur-such as an instrument breaking or pulling out of the bone in which it has been implanted. Although they are not life-threatening, these developments require surgical correction. Furthermore, in addition to the physical pain and discomfort associated with surgery, the psychological prospect of repeated operations can be quite discouraging. Finally, the amount of additional growth that is achieved using this technique is somewhat limited and may amount to no more than a few inches in height.

The primary drawback to proceeding to a definitive surgery is that although the spine is elongated by straightening the curve, the patient’s natural growth is arrested. The choice of surgical treatment is therefore often based on the age of the infant or child and how close they are to puberty and skeletal maturity.

Adolescent idiopathic scoliosis: In adolescents with progressive curves who have achieved full bone growth, definitive surgery is recommended. Performed successfully, no further treatment is needed. 

Anteroposterior (AP) view of the spine (standing) demonstrates surgical fusion.

Adult idiopathic scoliosis: As with adolescents, surgical treatment involves fusing the sites on the spine where the curve is developing, and implanting instruments to maintain correct alignment. In younger adults, the appearance of scoliosis may play a larger role in electing to have surgery. In older adults, surgical (and non-surgical) treatment can be complicated by the presence of other conditions including arthritis, kyphosis (forward curve of the spine) and osteoporosis (a condition in which bone density decreases and the bones become more fragile and likely to break on impact.) Although these patients can be successfully treated with surgery, the surgeon is faced with a more difficult task. In addition, in patients with osteoporosis, the implanted instruments may be more likely to pull away from the bone.

Recovery and Outcomes

Performed by an experienced orthopaedic surgeon, surgical treatment of scoliosis is a safe and effective procedure. Great care is taken to preserve and protect neurological function. While early recovery from the surgery is painful, large institutions like the Hospital for Special Surgery, have pain management specialists to assist patients during this time.

Young patients undergoing surgery for the placement of growing rods recover rapidly. These patients are usually out of bed within 2 days and home within a week. Young children return to their normal activities quickly and it may, in fact, be a challenge for parents to restrict these activities during healing. Surgical wounds also heal very quickly.

For patients undergoing definitive surgery (fusion and instrumentation): the hospital stay is usually less than a week. A brace may be worn briefly during recovery. And in most cases, the patient returns to all normal activities within 6 months to a year.

The extent to which surgical patients with scoliosis regain their range of motion varies depending on the sites at which the vertebrae are fused. If the treatment is primarily in the thoracic spine (the midportion, corresponding to the chest), normal mobility is achieved after the healing process is completed. If the lumbar spine (below the thoracic portion, near the loins or waist) is the site of treatment, sideways movement will be more restricted, although the patient will still be able to bend forward from the hips. Similarly, fusion in the neck places more restriction on movement.

Areas Of The Spine

Following surgery, many patients are eventually able to participate in almost all recreational activities and are advised only to refrain from contact sports and gymnastics.

Orthopaedic surgeons measure successful outcome in terms of correction, attaining spinal fusion, and return to normal function. The goal is also to achieve spinal balance and to avoid over-correction. The degree of correction sought is also dictated by the need to protect neurological function.

Innovative techniques aimed at reducing surgical trauma and incision involves use of endoscopic procedures (working through tiny holes in the chest to visualize the spine). Currently mild to moderate thoracic curves are being considered for such procedures.

The Scoliosis Service at HSS

The Scoliosis Service at the Hospital for Special Surgery (HSS) is made up of a multidisciplinary team of surgical and medical professionals with extensive experience in the treatment of scoliosis and other deformities of the spine. Under the direction of Dr. Oheneba Boachie-Adjei, the service provides non-surgical and surgical treatment for more than 1000 adult and pediatric scoliosis patients each year.

In addition to its reputation for excellence in correcting complex spine deformities in both children and adults, many physicians on the service are also involved in ongoing research on the causes and treatment of these conditions.

Frequently Asked Questions and Answers

Q: My 14-year-old daughter has just been diagnosed with idiopathic scoliosis. The doctor measured the curve on x-ray to be 20 degrees and said her bones are nearly fully grown. She does not have pain and the curve is hardly noticeable but we are concerned that it will continue to increase and become a big problem later in life.

A: Once your daughter is skeletally mature, when bone growth is complete, the curvature of the spine in idiopathic scoliosis will not increase and is unlikely to be a problem. Until this occurs she should continue to be evaluated once a year by an orthopaedic surgeon.

Q: My 10-year-old daughter has idiopathic scoliosis with a curve of 40 degrees. My orthopaedist has recommended surgery to implant growing rods and has explained that she will need multiple operations to make this treatment work. Can’t she have a single operation to address her condition?

A. Your daughter is at an age where it makes sense to explore the alternatives. Your orthopaedic surgeon may have suggested growing rods because he anticipates that your daughter has at least a few more years left before her bones fully grow and mature. Use of the growing rods gives her the best chance of achieving her maximum adult height. However, a child of this age may also be a candidate for definitive surgery (fusing the vertebrae and realignment of the spine using instrumentation) with the understanding that the area of the spine fused will not grow. She will continue to attain growth in the unfused levels of the spine and in the rest of the body. Bracing is also a reasonable alternative to allow additional growth for one or two years before surgery. Be sure to discuss all treatment options with your orthopaedist or another specialist in the treatment of scoliosis.

Q: I've heard that electrical stimulation can be used to correct scoliosis. Why isn’t my physician recommending this?

A: While use of this technique has been reported, there is no good clinical evidence to suggest that it offers any benefit to patients with idiopathic scoliosis.

Q: I'm scheduled to undergo surgery for scoliosis and am worried about damage to my nervous system. What are the risks of injury?

A: When performed by experienced orthopaedic surgeons, surgical treatment for scoliosis is considered extremely safe. Maintaining and protecting nervous system function is one of the surgeon’s highest priorities. In general, for uncomplicated adolescent idiopathic scoliosis, the reported risk of nerve injury with surgery is between 0.7-1%; in adults the rate ranges between 1 and 5%.

Q: What are the chances that additional surgery will be required for a 15-year-old adolescent undergoing a first surgical treatment for scoliosis?

A: If spine surgery has been properly performed in an adolescent, the chance that the patient will require revision surgery in the short to medium term is minimal. More than 98 percent of patients do well. Surgical complications are quite rare, and most patients leave the hospital within a week after surgery without pain or other problems with wound healing, or the instrumentation used to correct the spinal curve. The need for further surgery in the future will depend on the type of instrumentation that was used and the sagittal (vertical) alignment of the spine. Location of the area in which instrumentation was placed is also significant. Formerly, revision surgery in the long term was more common in patients with long fusions to the lower portion of the lumbar spine (the vertebrae closest to the pelvis). It appears that the current use of current segmental instrumentation systems that take into account the restoration and maintenance of spinal alignment, is reducing the chance that (longer term) revision surgery will be necessary.

Q: What is flatback and how is it prevented?

A: Flatback is the term used to describe a condition in patients whose backs lack normal lordosis (sway or curvature) and are therefore too rigid. Patients are unable to stand upright without bending their knees excessively and appear to be crouching. This is most commonly caused by distraction instrumentation placed in the lower portion of the lumbar spine that takes away some of the normal sway. Most patients are able to compensate by increasing the sway below the remaining segments, but over time these segments degenerate and the patients therefore lose the ability to maintain upright posture and then lean forward. Degenerative changes can also cause loss of lumbar lordosis, but this is less common. Today, skilled orthopaedic surgeons minimize the possibility of flatback by fusing fewer segments of the lumbar spine whenever possible. Rods used in instrumentation of the lumbar spine are prebent to conform to the normal curvature so as to permit proper sagittal (vertical) balance.

Q: What are the advantages of an anterior versus a posterior procedure?

A: The terms posterior (from the patient’s back) and anterior (from the front of the body) refer to the approach the surgeon takes in reaching the area of the spine to be treated. Most curves can be treated with a posterior procedure in which the surgeon uses segmental instrumentation and fusion. This type of surgery generally works best for thoracic curves and for double curves. A posterior approach is easier for the surgeon and offers the advantage of allowing two rods to be placed which obviates the need for external immobilization with a brace or other device. Traditionally, some special curves-such as thoracolumbar and lumbar deformities-- have been treated with anterior approach because it offers the advantage of fusing the fewest levels possible, and the ability to de-rotate the spine and provide three-dimensional correction of spinal deformity. Some surgeons have applied anterior instrumentation to thoracic curves but this is not a standard procedure.

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posted 9/24/2002

Diagnostic imaging examinations provided by HSS Radiologists *Summary Prepared by Nancy Novick