Pectus carinatum is a chest wall deformity where the breastbone pushes outward, creating a visible ridge or bulge in the center of the chest. Sometimes called “pigeon chest,” it’s the second most common chest wall deformity after pectus excavatum (a sunken chest). It affects roughly 1 in 2,500 births, with males four times more likely to develop it than females. The protrusion typically becomes noticeable during the growth spurts of puberty and can range from a subtle asymmetry to a pronounced outward projection.
What Causes the Breastbone to Push Out
The deformity results from an overgrowth of the cartilage that connects the ribs to the breastbone. As this cartilage grows faster than the surrounding bone during adolescence, it pushes the sternum forward. The exact trigger for this overgrowth isn’t fully understood, but it runs in families. About 25% of people with pectus carinatum have a relative with some form of chest wall deformity.
The most common form, called the chondrogladiolar type, involves the middle and lower portion of the breastbone projecting forward. A much rarer form affects the upper breastbone and upper rib cartilage. Some people develop a mixed pattern, where one side of the chest protrudes while the other appears sunken, creating an asymmetrical appearance.
How It Looks and Feels
For many people, the primary concern is cosmetic. The outward bulge is visible through clothing and can be a significant source of self-consciousness, particularly for teenagers. Beyond appearance, some people experience tenderness or pain directly over the protruding area, especially with pressure from seatbelts, backpack straps, or lying face-down.
The physical effects on breathing and exercise capacity are less straightforward than many people assume. A large study of 259 patients with chest wall deformities found that 64% reported shortness of breath during exercise and 41% reported chest pain. However, when researchers tested lung function and aerobic fitness objectively, true pulmonary limitations during exercise showed up in fewer than 3% of cases. Mild reductions in aerobic capacity were found in about 30% of patients, but resting lung tests correlated poorly with the actual severity of the deformity. In other words, the chest may look dramatically different without significantly limiting what your lungs can do.
Conditions That Overlap With Pectus Carinatum
Pectus carinatum sometimes appears alongside connective tissue disorders. Marfan syndrome is the most well-known association: roughly 60% of people with Marfan syndrome have some form of chest wall deformity, whether a protruding or sunken breastbone. Scoliosis is another common overlap, and the two conditions can appear together or independently. Recent CT-based studies suggest that mild, asymmetrical cartilage prominence may be present in 2% to 5% of the general population, meaning many mild cases go unnoticed or unreported.
Diagnosis and Severity Assessment
A doctor can usually identify pectus carinatum through a physical exam alone. The protrusion is visible and can be measured with calipers or assessed by pressing on the chest to gauge how flexible the cartilage is. This flexibility matters because it predicts how well the chest will respond to bracing.
Imaging plays a supporting role. A CT scan or chest X-ray helps rule out other structural issues and can quantify the degree of deformity. While the Haller index is widely used for pectus excavatum (the sunken version), pectus carinatum severity is often assessed clinically by measuring the pressure needed to flatten the protrusion. A lower pressure reading means the chest wall is more flexible and likely to respond to non-surgical treatment.
Bracing as First-Line Treatment
For most adolescents, a compressive chest brace is the first treatment offered. The brace looks like a lightweight vest with a firm pad that applies steady pressure to the protruding area, gradually reshaping the cartilage over months. It works best on growing teenagers whose cartilage is still pliable.
The catch is that results depend heavily on how many hours per day the brace is actually worn. In one clinical study, patients who wore the brace 15 or more hours daily achieved complete correction 39% of the time, with another 28% seeing significant improvement at 8 to 15 hours per day. Those who wore it fewer than 8 hours daily saw minimal improvement or no change at all. Most treatment protocols recommend 15 to 24 hours of daily wear, removing the brace only for sports, bathing, or swimming.
Timing also matters. Patients who start bracing before their growth plates are nearly closed (before late puberty) respond roughly twice as fast as those who begin later, achieving correction in about four months compared to eight. Continuing to wear the brace until skeletal maturity, even after the chest looks corrected, helps prevent the deformity from returning. Bracing becomes much less effective in adults whose cartilage has fully hardened.
When Surgery Is Needed
Surgery is reserved for people whose deformity doesn’t respond to bracing, who can’t tolerate long-term brace wear, or who have a rigid chest wall that won’t flatten under pressure. Two main surgical approaches exist.
The older technique, called the Ravitch procedure, is an open surgery where the surgeon removes strips of the overgrown cartilage and repositions the breastbone. It’s effective but involves a larger incision and a longer recovery. The newer Abramson procedure, introduced in 2005, is minimally invasive. A curved steel bar is placed over the sternum and anchored to the ribs, pressing the breastbone inward. Most patients go home within four days, with hospital stays ranging from two to six days. The bar stays in place for two to three years before being removed in a second, shorter procedure.
The Abramson technique has gained popularity because it avoids cartilage removal, leaves a smaller scar, and produces strong cosmetic results. A 20-year review of pectus surgeries found the main complications to be wound infection and bleeding, which are generally manageable. The recurrence rate across all surgical approaches was about 10% over an average follow-up of nearly nine years. No specific risk factors predicted who would experience a recurrence.
Living With Pectus Carinatum
The psychological impact of pectus carinatum is often underestimated. Teenagers frequently avoid activities that require removing their shirt, like swimming or team sports in locker room settings. Treatment decisions often weigh cosmetic and emotional concerns as heavily as physical ones, and that’s entirely reasonable.
For people with mild cases who choose not to pursue treatment, the deformity itself is not dangerous. It doesn’t worsen after skeletal maturity, and significant cardiac or pulmonary complications are rare in isolated pectus carinatum without an underlying connective tissue disorder. Exercise is safe and encouraged. Strength training that targets the chest muscles won’t correct the bone structure, but it can improve the overall appearance of the chest wall and build confidence.