Thoracic Insufficiency Syndrome

Overview

Thoracic insufficiency syndrome may result from a primary chest wall problem and/or from scoliosis. This can become so significant at a young age that it can impact normal lung development and growth which can affect the function of the chest in moving air in and out of the lungs.

Prognosis

Thoracic insufficiency syndrome impacts the development of a child in two distinct ways. The first is the inability to support normal respiration. A thorax in early stages of deformity from scoliosis or from fused or absent ribs may have a minor degree of inhibition of respiration, and the patient may appear normal. As the deformity worsens, the respiration can become more labored with increased breathing rate and the inability to keep up with playmates in play activities. When thoracic volume is severely decreased and the diaphragm is the only source of respiratory effort, then children may need aides such as nasal oxygen, BiPap (pressure mask delivering oxygen), or even ventilator support to maintain life-sustaining oxygen levels in their blood. The second component of thoracic insufficiency syndrome is the inability of the thorax to support lung growth. Early in life, a small thorax may be adequate for an infant, but if the child grows without the thorax enlarging with normal growth sufficiently to accommodate adult size lungs, then by the time the patient becomes a teenager, the thorax that was adequate during early childhood is very inadequate for adult oxygenation needs.

Treatment

Rib Based Systems, such as Vertical Expandable Prosthetic Titanium Rib (VEPTR), are systems used for treatment of thoracic insufficiency syndrome in skeletally immature patients. Thoracic insufficiency syndrome (TIS) is usually associated with uncommon three-dimensional deformities of both the spine and rib cage. Several types of rib-based expansion thoracoplasty operations can be used for different types of deformities to gain chest volume (to allow for growth of the underlying lungs) while indirectly correcting the scoliosis without spine fusion. This surgery can be extensive; devices are placed under the scapula (shoulder blade) and are attached to the ribs near the neck and continue down to either the ribs, spine, or to the pelvis near the waist (Figure 9). This helps to stabilize the surgically expanded chest wall constriction (expansion thoracoplasty). To keep up with a patient's growth, the devices are expanded twice a year in outpatient surgery through small incisions. Currently, there are a limited number of institutions offering rib-based surgery. Your child's spine surgeon can advise whether your child's condition is appropriate for this treatment option and to provide referral information, if needed. Some centers are using the rib-based devices as a means to straighten the spine indirectly via the ribs and chest wall.

Resources

http://www.chop.edu/service/thoracic-insufficiency-syndrome-center/index.html

http://www.srs.org/patient_and_family/scoliosis/early_onset_scoliosis/tis/