Under normal conditions, the adult spine is straight when viewed from the front and has a series of curves when viewed from the side. This alignment helps keep the body erect and the head up with a minimum of effort. Spinal deformities, or curves in the spine, often develop during growth in adolescence or as a result of aging. In some cases, they can progress during the adult years as well.

Several curve problems may occur.

• Scoliosis is a frontal spinal deformity, meaning that the normal straight alignment of the spine from the front is affected by a curve to the left or right. Scoliosis usually occurs during childhood and may be corrected or stabilized at that time. While the curve progression usually ends when the skeleton stops growing, curves may begin or progress in adulthood. Curve progression in adulthood usually takes place slowly-1 to 2 degrees per year. Because scoliosis occurs in the upper spine, the ribs often are affected as well. Adult scoliosis may be idiopathic (having no identifiable cause) or may be the result of a genetic condition, such as achondroplasia (a condition that results in a form of dwarfism) or spinal muscular atrophy (a condition in which spinal muscles wither).
• Kyphosis is a condition in which the upper back curves forward, perhaps creating the appearance of a hump in the back. Kyphosis may result from years of poor posture, spine fractures associated with osteoporosis, trauma, or developmental problems.
• Lordosis, or swayback, is a spinal deformity that occurs when the lower back curves inward more than normal. Lordosis also may be caused by osteoporosis or spondylolisthesis, a slippage of vertebrae. Obesity, congenital disorders, or overcompensation for kyphosis also may contribute to swayback.

All spinal deformities are a combination of these curve problems and rotation of the spine.

Symptoms

Spinal curves are mild in many patients and may not cause symptoms. However, in some cases a curve may progress in adulthood, creating abnormal strains and loads on the spine and leading to pain, degeneration of spinal structures, and cosmetic problems. Degeneration of discs and vertebrae may also lead to increasing curvature. In severe cases, breathing also may be affected.

Diagnosis

Diagnosis of adult spinal deformities consists of a thorough physical examination and a series of x-rays of the torso. In addition, some patients may undergo a pulmonary function test to see if breathing is affected. Magnetic resonance imaging (MRI) scans also may be used to identify a tumor or infection that may be contributing to spinal instability.

Treatment

Many adult spinal deformities are stable and do not require treatment. When they do progress, the progression usually is slow, so there may not be great urgency in treatment. When the progression persists or chronic pain occurs, treatment includes both nonsurgical and surgical interventions.

Nonsurgical treatments, such as oral pain medication and physical therapy can help control pain. Children and adolescents with spinal deformities usually do better with nonsurgical interventions because their bones still are developing. Bracing, for example, is a common treatment for children and adolescents, but is less effective in adults because their spinal joints are more rigid.

In cases of ongoing curve progression or chronic pain, surgery is necessary. Surgery usually involves mechanical stabilization of the spine and a spinal fusion procedure. Hooks, rods, and screws are used to fix the spine, and then bone taken from another part of the body or from a bone bank is implanted to encourage bone to grow across the joints, preventing the curve from progressing. Bone growth may be encouraged with bone morphogenic protein, a biologic product that stimulates the creation of new bone. In addition, these procedures may require the removal of tissue, including intervertebral discs, vertebrae, spinal muscles, and ribs.

No bracing is required following surgery and the results usually are excellent. Most patients recover 90 percent of their normal function within 6 to 8 weeks.