Pectus carinatum

pectus carinatumPectus carinatum (also known as pigeon chest or keel-shaped deformity of the chest) is a chest deformity in which the sternum (the breastbone) is protruded .


Description


Pectus carinatum is a skeletal abnormality in which the anterior chest wall is pushed outward. Commonly affected individuals have no symptoms except the concern about their physical appearance. This may cause anxiety, depression and affect social life.

Carina is a Latin word for keel.


Causes

The protrusion of the chest is caused by the overgrowth of costal cartilage. Commonly it occurs during a growth spurt more likely in males, although in some cases pectus carinatum is present shortly after the birth, it appears as a rounded anterior chest wall. As the child grows the protrusion becomes more evident.

The deformity of the chest wall may be caused by vitamin D deficiency (rickets). Rarely the deformity may occur after open-heart surgery or in children who suffer from bronchial asthma.

A genetic predisposition may also be an issue as long as in 25% of cases an affected person has a family member with the same condition.

Some patients develop a rigid chest wall that fails to change the diameter during expiration. As the result the vital capacity of the lungs reduces and they lose compliance. Hypoventilation causes cardiac disorder called cor pulmonale.


Risk factors


The condition may be associated with other syndromes:

  • Turner syndrome,
  • Noonan syndrome,
  • Loeys-Dietz syndrome,
  • Marfan syndrome,
  • Ehlers-Danlos syndrome,
  • Morquio syndrome,
  • trisomy 18, trisomy 21,
  • homocystinuria,
  • osteogenesis imperfecta,
  • multiple lentigines syndrome (LEOPARD syndrome),
  • Sly syndrome (mucopolysaccharidosis type VII),

 

Symptoms

Pigeon chest is classified due to the appearance of the chest. The main types are chondrogladiolar and chondromanubrial (also known as pectus arcuatum). The most common is the chondrogladiolar form, characterized by a symmetric protrusion of the sternum and costal cartilages. Pectus arcuatum (Currarino–Silverman syndrome or pouter pigeon deformity) includes a manubrial (affecting the broad upper part of the sternum called manubrium) and upper sternal protrusion, particularly also at the sternal angle.

The deformity may be seen shortly after the birth and in an early childhood, although typically it becomes apparent when the child is 11 or 12 years old. Commonly the condition is asymptomatic, although it may make people feel uncomfortable and concerned about their appearance.

Some individuals may experience

  • difficulties breathing (dyspnea) during exercise or other activities;
  • tachypnea (rapid breathing);
  • tachycardia (rapid heart rate);
  • fatigue;
  • recurrent respiratory infections;
  • asthma (in 22% of cases);
  • chest pain and tenderness;
  • low self-esteem.


Diagnosis

To evaluate the diagnosis an X-ray examination of the chest is performed. A chest CT or MRI may also be used.

Other tests (ECG, echocardiography, spirometry,  etc.) may also be needed to estimate the function of the internal organs.

Treatment


The first line therapy in young patients who have malleable chest walls (commonly until the age of 18) is an orthotic bracing. This therapy alone was found to be effective in 65-80% of cases. Unfortunately, such therapy is not helpful for older individuals due to the rigid chest walls.

For those persons surgical treatment is recommended. It may be Endoscopic resection of costal cartilage with a sternal osteotomy or open surgical repair, although the first option has a better cosmetic outcome.