Pectus excavatum is a common congenital chest wall deformity where the breastbone appears sunken into the chest. This condition, also known as funnel chest, creates a noticeable depression in the anterior chest wall. It stands as the most frequently occurring chest wall anomaly.
What Pectus Excavatum Is
Pectus excavatum is characterized by an inward growth of the sternum, or breastbone, and the ribs connected to it, resulting in a concavity in the center of the chest. This depression can range from a subtle dip to a deep, severe indentation. The affected area typically involves the third to seventh costal cartilages and ribs, with the deepest part of the deformity often appearing near the bottom of the breastbone. The physical presentation of pectus excavatum varies among individuals. Some may exhibit a symmetrical indentation, where the depression is centrally located. Others might have an asymmetrical presentation, with the inward curve being more pronounced on one side of the chest or involving other areas of the ribcage.
How Often Pectus Excavatum Occurs
Pectus excavatum affects approximately 1 in 300 to 1 in 400 live births. Some reports indicate a prevalence ranging from 1 in 40 to 1 in 1,000 individuals across various populations. In adults, studies have estimated its occurrence to be around 0.4%, or 1 in 250 individuals. The condition shows a higher incidence in males compared to females, with males being affected about three to five times more frequently. While often noticeable shortly after birth, the characteristic sunken chest appearance can become significantly more pronounced during childhood and adolescence, particularly during pubertal growth spurts. This increased visibility during growth phases often leads to diagnosis or increased concern.
How Pectus Excavatum Develops
The exact cause of pectus excavatum is not fully understood, but current theories suggest it results from abnormal growth of the costal cartilages, which are the flexible tissues connecting the ribs to the breastbone. This excessive or irregular growth causes the cartilages to push the sternum inward, creating the characteristic depression. Genetic factors play a role in the development of pectus excavatum, as it can run in families. A family history of the condition is reported in about 40% to 53% of cases, indicating a likely genetic predisposition. While no specific gene has been definitively identified as the sole cause, the familial pattern suggests an inherited component. Pectus excavatum can also be associated with certain connective tissue disorders. These include conditions such as Marfan syndrome, Ehlers-Danlos syndrome, and osteogenesis imperfecta. In these instances, the underlying connective tissue weakness may contribute to the atypical chest wall development.
Potential Health Considerations
The physical impacts of pectus excavatum can vary widely depending on the severity of the chest wall indentation. In mild cases, individuals may experience no physical symptoms. However, more severe cases can affect the function of the heart and lungs. Physical symptoms can include shortness of breath, particularly during physical activity, reduced exercise endurance, and fatigue. Some individuals may also experience chest pain, a fast heart rate, or heart palpitations. The inward sternum can compress the lungs, limiting their full expansion, and may push the heart to the left. Beyond the physical effects, pectus excavatum can have significant psychological impacts, especially during adolescence. Concerns about body image are common, leading to self-consciousness and social anxiety. Individuals may feel embarrassed by their appearance, which can result in decreased self-esteem and avoidance of activities where their chest might be exposed.