Spinal Deformities
A Patient's Guide to Spinal Deformity/Scoliosis
The spine is a flexible, segmented column constructed of multiple bones and joints (disks and facet joints) which are supported by various muscles and ligaments. The entire system is delicately balanced in order to allow individuals to stand upright with minimal energy exertion.
When viewed from the front, the spine is normally straight. However, when viewed from this side, the spine demonstrates a series of curves. In the cervical (neck) area, the spine curves gently towards the front. In the thoracic (chest) area the spine has a backward curve. Again, in the low-back area (lumbar spine) the curve is towards the front.
The overall result of these curves is that the head is balanced above the center of the pelvis. In the ideal state, minimal energy expenditure is necessary to maintain the head in this position when in relaxed, upright stance. The force of body weight is fairly evenly distributed between the disc in the front and the facet joints behind.
Occasionally, in certain individuals, this normal spinal alignment will be disturbed. Individuals can develop an abnormal spinal alignment in either the frontal plane (scoliosis), or the sagittal plane (kyphosis or lordosis).
In actual fact, no spinal deformity exists in only a single plane; all spinal deformity is some combination of scoliosis, kyphosis or lordosis. Mild degrees of spinal deformity are quite common and well tolerated. Occasionally in certain individuals, spinal deformity can become large and require medical or surgical treatment.
Scoliosis
Scoliosis is a lateral bending of the spine. There are many causes of scoliosis, but the most common type is termed "idiopathic". This means that the actual cause is unknown. A great deal of research is currently underway to try to determine the cause of idiopathic scoliosis. Scoliosis can begin to develop in early childhood or even in adulthood, but the most common time to develop a spinal curvature is during the adolescent growth spurt.
The thoracic spine is the most common site of scoliosis. Thoracic scoliosis is generally associated with deformity of the rib cage as well as the spine itself. The curvature becomes clinically apparent because of the rib cage asymmetry that develops. There may be elevation of one shoulder as well. Other manifestations of scoliosis include an apparent leg length discrepancy. In most cases, scoliosis is not associated with any pain.
During growth, scoliosis can progress fairly rapidly. During adolescence, curves may increase in magnitude up to one or two degrees per month. Bracing has been shown to be an effective method to control curve growth. Bracing cannot permanently correct the curve. Bracing is only effective in relatively immature patients and in curves below 40 degrees. Above this size, braces are relatively ineffective in controlling curve growth.
Certain types of scoliosis are also not amendable to brace treatment such as when there is frank thoracic lordosis. Many patients present for evaluation when they are already too close to skeletal maturity for brace use to be effective. Bracing cannot prevent adult curves from progressing although a brace may be prescribed for pain control in the adult.
Although fitness and exercise can be generally recommended for spinal health, there is no series of exercises that has been demonstrated to be consistently effective in preventing the progression of a scoliotic curve. Likewise, electrical muscle stimulation is not effective in stopping the progression of scoliosis.
Scoliosis Surgery
Surgery for scoliosis is generally recommended in the adolescents with large curves who have significant growth remaining. The larger the curve at the end of growth, the more likely it is to progress in adulthood. Surgery for scoliosis involves correction of the curve and fusion of some portion of the spine. The correction is obtained through the insertion of internal fixation (rods). The rods are connected to the spine by a series of hooks, screws and wires. This internal fixation maintains the correction until a solid fusion is obtained. Generally, some form of bone graft material is used to help promote fusion.
There are many different spinal fusion and instrumentation techniques that can be used for the correction of scoliosis. Fusion can be accomplished either anteriorly (through removal of disks) or posteriorly. The fusion technique and the amount of the spine that requires instrumentation is specific to each individual case and can only be determined through clinical examination and careful analysis of X-rays and other imaging studies.
Adult Scoliosis
Adult scoliosis is somewhat different from the adolescent variety. Many patients may have some residual curvature from childhood, which was not sufficient to require treatment but which progresses after the end of growth. However, it is possible for curves to begin in adulthood.
Many factors may contribute to the development of scoliosis in adults. Curves tend to be much more slowly progressive (generally in the range of one or two degrees each year). Curve progression may be associated with the disc degeneration and spinal arthritis. Pain may be related to nerve root impingement from spinal stenosis or the degenerative spinal arthritis itself.
The alteration in the mechanics of the spine brought about by the spinal deformity can also be a source of pain in and of itself. In many cases, the pain related to adult scoliosis can be managed without surgery. Medication, exercise, physical therapy, bracing, smoking cessation end weight loss are all common methods used to help control back pain related to scoliosis.
Surgical treatment of scoliosis in adults is reserved for patients with intractable severe pain, which is refractory to a prolonged period of non-surgical treatment or for patients who demonstrate significant curve progression following skeletal maturity. The surgical treatment of adult scoliosis is similar to adolescents in the sense that internal fixation and fusion are generally required. However, adults often require more extensive surgery than children.
Their curves are more often rigid and are more difficult to correct. Significantly degenerated segments need to be incorporated into the fusion construct. Also, adults do not fuse their spines as readily and require more extensive techniques to ensure that a solid fusion is obtained. Adult scoliosis is more likely to be associated with kyphosis and require anterior column reconstruction in order to fully address the spinal deformity in three dimensions.
Surgery for scoliosis can be extensive and the risk of complications exists. Complications can include anesthetic complications, bleeding, infection, loss of correction, failure to obtain a solid fusion, instrumentation loosening or breakage as well as neurologic complications. Other complications exist is well.
Each patient should have a thorough discussion with their doctor prior to surgery so that they understand the potential complications that can occur with this type of surgery before they agree to proceed with surgery.
The length of hospitalization and recovery vary depending upon the magnitude of the surgical procedure. Adolescents generally are in the hospital for less than one week and are ready to return to school about six weeks following surgery. Adults take longer to recover. Using modern instrumentation techniques, postoperative bracing is rarely required.
Returning to full activities is prohibited until a solid fusion is seen on X-ray. This may take several months but once the fusion is mature, most patients can return to all their normal activities, without limitations. Surgery for scoliosis, in general, is highly successful. The majority of patients experience significant relief of pain and improve cosmetic appearance. The benefits of this surgery are substantial.