Pectus carinatum, also known as pigeon chest, is a medical condition where the sternum (breastbone) and ribs move outward, giving the chest a birdlike appearance. It occurs in 1 out of every 1500 children, more often in boys than girls. Currently, there are effective braces made specifically for this condition.
Pectus carinatum is also known as pigeon chest since its appearance resembles a bird.
In the pectus carinatum, the sternum (breastbone) and ribs are pushed outward.
It occurs in 1 out of every 1500 children, boys more often than girls.
The appearance can have psychological effects, leading to problems with interpersonal relationships.
There are three treatments: braces, surgical correction, and cosmetically masking the condition.
What are the structures involved in pectus carinatum (pigeon chest)?
On the right side of diagram 1, you can see the outward protrusion at the center of the chest in a child with pectus carinatum.
On the left side of the diagram are two cross sections taken of the chest wall. Even though cross sections can be confusing, you can easily understand them by visualizing a person lying flat on a table with their feet towards you. Then the imaging cut is taken in the middle of the chest and pulled upwards to produce the cross-sectional view.
On the upper left side of the diagram, you can see a normal cross-section, while on the lower left side of the diagram, you can see a cross-section of pectus carinatum, with the sternum and ribs pushed outwards (upwards on the cross-sectional view).
What causes pectus carinatum?
The exact cause of pectus carinatum is unknown; however, it is associated with other genetic disorders, including Marfan syndrome and Trisomy 21. In addition, studies have shown that 25% to 30% of family members of an affected person also have some chest wall deformity, suggesting there is a genetic component.
Congenital pectus carinatum is a type of pectus carinatum that children have when born.
What are the complications of pectus carinatum?
Most children with pectus carinatum can have a normal-appearing heart and lungs, even though they don't always function at maximum levels, leading to fatigue. In addition, 15% of children with pectus excavatum will develop scoliosis (curvature of the spine).
Psychological conditions can result due to issues with appearance, self-image, and self-confidence, leading to difficulties in interpersonal relationships.
How is pectus carinatum diagnosed?
A history may elicit more shortness of breath with exercise than their peers.
The physical exam will demonstrate the forward protrusion of the chest wall and ribs. Additionally, there may be lateral curvature of the spine (scoliosis) or shoulders with differing heights.
Plain x-rays are done first to view for any underlying bony abnormalities, such as scoliosis, fracture (break), or spurs (bony prominences at the edges of the bones).
Most cases can be diagnosed with plain x-rays, but some require a computed tomography (CT or CAT) scan since it shows three-dimensional cross-sections (like in diagram 1).
What is the treatment for pectus carinatum?
Treatment is divided into three categories: braces, surgical treatment, and cosmetic procedures (to hide the deformity).
Braces are the first-line treatment. The braces can go over or under the clothes and are worn for 14-24 hours daily. They are most effective if used before age 19 and the child’s growth spurt; the chest wall structures become more rigid after age 19 and the growth spurt.
The brace works by placing pressure on the sternum (breastbone), ribs, and cartilage, to push them back to normal shape. The brace will need adjusting as the deformity decreases and the child grows. The image below shows the pectus carinatum brace. The required brace varies, depending on the child and the degree of protrusion. There are also numerous other braces available.
The brace often corrects the pectus carinatum, and no surgery is needed. However, braces work best when the deformity is non-complex, flexible, and the child is compliant. Unfortunately, the lack of compliance is the most common reason the brace does not correct the deformity.
The classic type of surgical procedure for pectus carinatum was designed by Dr. Mark Ravitch in 1949. It involves cutting the pectoralis major muscle and elevating it, along with removing the damaged cartilage. Most cases involved placing a metal bar to keep the structures in place.
A newer procedure, the Abramson procedure, is now being used and has become the surgery of choice. An incision is made at the lateral (side) chest wall, and a modified metal bar, called a Nuss bar, is inserted. This is considered less invasive since the incisions (cuts) are much smaller.
3. Cosmetic concealment
Cosmetic concealment involves masking the pectus carinatum, so it's not as obvious. Even though it doesn't correct the anatomical deformity, it helps with appearance, improving the child’s self-confidence and psychological state.
Bodybuilding can improve the pectoralis muscle tone for boys, while breast augmentation is sometimes used for girls.
What is the prognosis for pectus carinatum?
A prognosis is a forecast or outcome of a disease. The prognosis in pectus excavatum is excellent, with no long-term negative health issues. With the three types of treatment mentioned above, the child can live a happy life.