What are the other Names for this Condition? (Also known as/Synonyms)

• Congenital Keeled Chest
• Keeled Chest

What is Pectus Carinatum? (Definition/Background Information)

• Pectus Carinatum is a rare congenital abnormality of unknown origin affecting the ribcage. It is also known to occur with other conditions, such as Marfan syndrome, Ehlers-Danlos syndrome, and homocystinuria
• Children with this condition have a pigeon chest appearance (bird-like chest), due to an outward protrusion of the ribs and sternum. The chest appears projected out and the condition may be mild or severe
• Based on the intensity of Pectus Carinatum, there may be other associated conditions like scoliosis, mitral valve prolapse, and other connective tissue disorders. The individual may also suffer psychological trauma and self-image issues
• With prolonged treatment and use of surgical procedures (if necessary), the defect can be corrected to a certain extent, which can significantly decrease the burden of the associated signs and symptoms

Who gets Pectus Carinatum? (Age and Sex Distribution)

• The disorder affects the newborn child (it is present at birth), but is sometimes not visible until teenage
• A male child is affected more often by Pectus Carinatum, than a female child (by a 4:1 ratio)
• No ethnic or racial predilection is observed

What are the Risk Factors for Pectus Carinatum? (Predisposing Factors)

The risk factors for Pectus Carinatum are:

• The disorder runs in the families. Children born in families with a medical history of the condition, have a higher risk
• Mitral valve prolapse and Noonan syndrome are common conditions of the heart, associated with this disorder
• Those suffering from connective tissue disorders, like Marfan syndrome and Ehlers-Danlos syndrome, have a greater chance of being affected by Pectus Carinatum
• Children with trisomy defects (a kind of genetic disorder), such as trisomy 18 (Edwards syndrome) and trisomy 21 (Down syndrome)
• Individuals with osteogenesis imperfecta, multiple lentigenes syndrome, and Morquio syndrome, also have an increased chance of Pectus Carinatum

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Pectus Carinatum? (Etiology)

• The exact cause of Pectus Carinatum is uncertain. It can occur spontaneously, by its own, even when there is no suspected reason or causal factor, such as a family history of the disorder, or known congenital abnormalities
• Excessive growth of the tissues that connect the ribs to the sternum (breastbone), and other bone-related defects, cause the sternum to move or bulge outwards at the center of the chest , giving a projected bird’s chest-like appearance
• Sometimes, during early infancy stages, the bones of the ribcage and breast-plate fuse together, due to certain medical complications (such as Noonan syndrome); this leads to Pectus Carinatum
• It is reported that the chest abnormality could be a genetic condition. Hence, individuals with a positive family history, may have a high risk
• However, it has occurred in association with certain medical complications and disorders, such as Marfan syndrome and Ehlers-Danlos syndrome, too

What are the Signs and Symptoms of Pectus Carinatum?

In some children with Pectus Carinatum, the outward chest protrusion may be almost invisible (a mild case of the disorder). However, it may progressively worsen during the preteen years and significantly affect the individual, going into adulthood.

The following signs and symptoms may be noted:

• In most cases, the condition is asymptomatic (in young children)
• Some children may experience chest pain and early exhaustion even with a little exertion, such as mild exercising, or with any other routine physical activity
• The heart and lung usually have a normal development. But, due to this abnormal structure of the chest, there may be functional defects leading to shortness of breath, mild asthma, and mitral valve prolapse
• Scoliosis (curved spine) may be observed
• Signs and symptoms that are typical of associated connective tissue disorders

How is Pectus Carinatum Diagnosed?

A simple physical examination of the chest condition may or may not be conclusive enough for the physician. In order to understand the extent of the condition and other medical problems associated with Pectus Carinatum, certain diagnostic tests are performed. Such studies also help in assessing the treatment or surgical options, and these tests include:

• X-ray of the chest: In order to study the degree of protrusion, and to analyze to what extent the heart and lungs have been affected
• CT scan of the chest
• Tests to assess the lung condition, including lung function test, exercise test
• Tests to assess the heart condition, including electrocardiogram (ECG) and echocardiogram

The following tests may be conducted to eliminate other related conditions:

• Metabolic studies performed as blood tests
• Lab tests for studying enzyme activities
• Chromosomal studies to understand the kind of genetic disorder that may be responsible for the anomaly

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Pectus Carinatum?

Complications of Pectus Carinatum are mainly linked to the extent of the condition and the presence of secondary medical disorders. These include:

• In very rare cases severe arthritis, vision problems, and other structural chest deformities have been observed
• The individual could suffer psychological stress and depression, due to Pectus Carinatum
• The disorder may prevent individuals from participating in certain sports activities (especially swimming, running)
• An abnormal posture may result in improperly aligned joints. This may prevent individuals from performing certain work-related physical activities, such as climbing a ladder, or operating certain machinery

How is Pectus Carinatum Treated?

The treatment measures for Pectus Carinatum are basically meant to correct the defect and the interventions could be surgical or non-surgical. Surgical methods are mainly used if the condition is classified as severe, by the physician. In most cases, non-surgical procedures form the usual line of treatment.

The treatment measures include:

• External bracing: A customized bracing is worn for a period of time by the individual (usually children, teens, and young adults), which applies a constant and direct pressure on the chest wall. This method is the most preferred one, due to its non-invasive nature and a lower risk for unwanted complications
• Surgical corrections are meant for severe cases of Pectus Carinatum. In order to obtain the best results, surgeries are performed in children or teens, between the ages of 8-18 years. The procedures may include any of the following:
  • Nuss procedure
  • Ravitch procedure
  • Reverse Nuss procedure.
• If the chest (outward projection) appearance is symmetric, then upper body strengthening exercises (or bodybuilding) is recommended by some healthcare providers (after the teenage period).To some extent, this can visually mask the appearance of the chest protrusion

How can Pectus Carinatum be Prevented?

• Currently, the exact cause of Pectus Carinatum is unknown, and it cannot be prevented
• Genetic testing of the expecting parents (and related family members) and prenatal diagnosis (molecular testing of the fetus during pregnancy) may help in understanding the risks better during pregnancy
• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child

What is the Prognosis of Pectus Carinatum? (Outcomes/Resolutions)

• Pectus Carinatum can be managed using both invasive and non-invasive techniques. The success of the treatment measures, also depend on the severity of the condition
• In some individuals, the restoration of the chest condition or profile, to near normalcy, may take many years. In case of severe complications affecting the heart and lungs, intensive treatment for a prolonged period of time may be required
• The prognosis is also influenced by the presence and severity of any associated disease and disorders (such as connective tissue disorders, Marfan’s syndrome), which may worsen the outcome

Additional and Relevant Useful Information for Pectus Carinatum:

There are voluntary organizations and support groups that provide help and support to the individuals affected by Pectus Carinatum.