Pectus Carinatum (A chest wall deformity)
What is pectus carinatum?
Often called "pigeon breast," pectus carinatum is caused when the sternum (breastbone) is pushed outward. The forward protrusion of the sternum often causes pain during exercise or during times of increased respiratory effort. This abnormality is seen predominantly (75%) in boys, and develops somewhat later in them than it does in girls. It increases in severity with age and generally worsens during growth spurts that occur during late childhood and adolescence. Although pectus carinatum occasionally interferes with overall health, it generally does not interfere with cardiorespiratory (heart and lung) functioning.
What causes pectus carinatum?
The cause of this abnormality is unknown, but the fact that it tends to recur in families suggests that genetics may play a role. Excessive growth and structural abnormalities of cartilage (tough, connective tissue) of the ribs and breastbone are present in pectus carinatum. Also, it is seen in some inherited connective tissue disorders such as Marfan syndrome and Ehlers-Danlos syndrome, and in homocystinuria, which is a metabolic disorder. When pectus carinatum is present in infancy, it is sometimes associated with premature fusion of segments of the sternum and ribs and congenital heart disease (Noonan syndrome).
What are the symptoms of pectus carinatum?
For the most part, children with pectus carinatum do not experience symptoms. However, some children may occasionally have difficulties playing and exercising and some may have tenderness and intermittent pain in the area of overgrown cartilages.
Are other conditions seen in children with pectus carinatum?
Some children with pectus carinatum also have scoliosis (curvature of the spine). Some have mitral valve prolapse, a condition in which the heart mitral valve functions abnormally. Connective tissue disorders involving structural abnormalities of the major blood vessels and heart valves are also seen. Although rarely seen, some children have other connective tissue disorders, including arthritis, abnormal growth, visual impairment and healing impairment.
How is pectus carinatum diagnosed?
Most patients undergo a chest X-ray during their initial evaluation. This helps the surgeon screen for other chest abnormalities or scoliosis. A computed tomography (CT) scan may also be performed to define the anatomy of the chest. In severe cases of respiratory symptoms, a pulmonary function test may be performed to determine the degree to which lung function is compromised.
Additionally, an electrocardiogram (ECG or EKG) and an echocardiogram may be performed. An ECG is a test that records both normal and abnormal electrical activity of the heart. An echocardiogram is a procedure that uses sound waves to study the structures and function of the heart.
How is pectus carinatum treated?
External bracing technique
In children up to age 18 who have mild to moderate pectus carinatum and are highly motivated to avoid surgery, the use of a custom-fitted chest-wall brace pushing directly on the sternum produces excellent outcomes. Willingness to wear the brace as required is essential for the success of this treatment approach. The brace works in much the same way as orthodontics (braces) works to correct the alignment of teeth. It consists of front and back compression plates that are anchored to aluminum bars. These bars are bound together by an adjustable leather strap on each side. This device is easily hidden under clothing and must be worn over a T-shirt for 14 to 16 hours a day for a minimum of two years or until full height is reached. Children are taught how to tighten the straps of the brace so to gradually increase the pressure applied to their chest. Parents learn how to check to see if adequate pressure is being applied. Pediatric surgeons monitor progress at office visits every six months.
Cincinnati Children's Hospital Medical Center is currently one of only a few centers in the country to offer this non-surgical option. Results of a recent study conducted by our team of pediatric surgeons found that most children managed with bracing showed significant correction of their deformity within the first year of treatment. This study will be published in the January 2006 issue of the Journal of Pediatric Surgery.
Surgery
In children who are not candidates for bracing, surgery may be necessary to restore normal chest contour. Open surgery in boys is performed through a horizontal incision on the anterior chest wall, usually just below the nipple area. In girls, this incision is placed to coincide with the lower breast margins when possible. The lower four to five cartilages that are abnormal are removed, leaving the perichondrium (the lining that envelops the outer portion of rib cartilage). This allows the cartilage to regrow in its new position. The sternum is surgically fractured and placed in the correct position. The incision is usually closed with internal sutures that minimize scarring.
The length of hospital stay following surgery is typically three to four days, but children often experience some discomfort for several weeks. For several days following surgery pain can be well controlled by epidural analgesia catheters or intravenous narcotics. Milder pain is managed with oral medication. Although minor complications sometimes occur, these are quite easy to treat. Cosmetic and physical outcomes in children who have undergone surgery in mid-childhood or early adolescence are generally excellent.
Rev. 9/07
