A divot or indentation in the center of your chest is most likely pectus excavatum, the most common skeletal deformity of the chest wall. It affects roughly 1 in 250 adults and happens when the breastbone (sternum) grows inward instead of sitting flat, creating a visible dip that can range from a shallow cosmetic concern to a deep depression that crowds the heart and lungs. Some people notice it in childhood, while others don’t pay attention until their teens or adulthood, when growth spurts or weight changes make it more obvious.
What Causes the Indentation
The honest answer is that the exact cause isn’t fully understood. For decades, the leading theory was that the cartilage connecting the ribs to the breastbone grew too fast, pushing the sternum inward. But research comparing rib-to-cartilage ratios in people with and without the condition found no evidence of cartilage overgrowth. The cartilage ratios in affected individuals were actually the same or smaller than in people with flat chests.
What is well established is that genetics play a major role. About 40% of people with pectus excavatum have a family member with a similar chest wall shape. The inheritance patterns vary widely, even within the same family, which helps explain why one sibling might have it while another doesn’t. The condition is also associated with connective tissue disorders that affect how the body’s structural proteins develop, which may explain why the cartilage and bone don’t hold their normal shape during growth.
Other Conditions That Cause a Chest Divot
Pectus excavatum is the most common explanation, but it isn’t the only one. Poland syndrome is a rare congenital condition where the chest muscles on one side are partially or completely absent, sometimes along with underdeveloped ribs. This creates an asymmetric indentation, typically on just one side, rather than the centered funnel shape of pectus excavatum. Poland syndrome also involves differences in the breast, nipple, or hand on the affected side, so it’s usually distinguishable.
Localized muscle atrophy from injury, surgery, or nerve damage can also create a visible dip. If your divot appeared suddenly, sits off-center, or developed after a chest injury, these possibilities are worth exploring with a doctor.
How It Affects Your Body
Many people with a mild divot have no physical symptoms at all. The chest looks different, but the heart and lungs function normally. Problems tend to scale with depth: as the indentation gets deeper, the breastbone presses closer to the heart and spine, physically limiting how much the heart can expand with each beat.
Research using exercise testing shows that the body compensates in a predictable sequence as severity increases. First, the heart rate climbs higher than expected during moderate exercise because each heartbeat pumps less blood. As the depression gets deeper, the volume of blood pumped per beat drops further. In the most severe cases, overall oxygen uptake during peak exercise declines measurably. This is why some people with pectus excavatum feel winded during activities that don’t seem to bother their peers, or notice their heart racing with relatively light effort.
For adults, these limitations may not become noticeable until the late 30s or 40s, when the body’s natural ability to compensate starts to decline with age. There’s no evidence that pectus excavatum causes progressive damage to the heart or lungs or shortens life expectancy, but symptoms like exercise intolerance and shortness of breath can worsen over time without treatment.
How Severity Is Measured
If you see a doctor about your divot, they’ll likely order a CT scan and calculate something called the Haller Index. This is a simple ratio: the width of your chest divided by the distance from your breastbone to your spine at the deepest point of the indentation. A normal chest has a Haller Index around 2.5. A value above 3.2 is considered significant, and values above 3.25 are the threshold where measurable effects on heart and lung function start to appear on exercise testing.
The Psychological Side
For many people searching this question, the concern isn’t really about breathing or heart function. It’s about how the chest looks. Research consistently finds that adolescents and young adults with chest wall deformities report impaired body image, reduced self-esteem, and social avoidance, even when they don’t meet criteria for a psychiatric diagnosis. Concealment behaviors are common: avoiding pools, beaches, locker rooms, or any situation that requires removing a shirt. This psychological burden is real and recognized as a legitimate reason to pursue treatment, not just a cosmetic vanity.
Treatment Without Surgery
A device called a vacuum bell offers a nonsurgical option, particularly for younger patients. It works like a large suction cup placed over the chest, gradually lifting the sternum outward with repeated use over months or years. In a study of 72 patients, 25% achieved excellent correction and another 18% achieved good correction based on imaging measurements.
Age matters significantly. Patients who started before age 11 were nearly four times more likely to see meaningful improvement compared to those who started later, likely because the chest wall is still flexible and growing. Using the device consistently for at least 24 consecutive months also nearly quadrupled the odds of a good result. For adults with a deep or rigid deformity, the vacuum bell is less likely to produce dramatic changes, though some still find modest improvement.
Surgical Options
Two main surgeries correct pectus excavatum. The Nuss procedure, introduced in 1998, is minimally invasive: a curved metal bar is inserted through small incisions on either side of the chest and positioned behind the breastbone to push it outward. The bar stays in place for two to three years, then is removed in a second, shorter procedure. It’s quicker than the alternative, involves less blood loss, and avoids cutting into bone or cartilage.
The Ravitch procedure is the older, open approach. It involves removing sections of the deformed cartilage and repositioning the breastbone, sometimes stabilizing it with a bar as well. It’s a bigger operation with a longer incision.
For children and teenagers, complication rates and reoperation rates are similar between the two procedures, around 6% for reoperation with either approach. The picture changes for adults. Adults undergoing the Nuss procedure have a notably higher complication rate and a reoperation rate of about 29%, compared to roughly 5% with the Ravitch approach. Bar displacement, where the metal bar shifts out of position after surgery, is also significantly more common with the Nuss technique. For this reason, many surgeons favor the Ravitch procedure for adult patients, while the Nuss procedure remains the go-to for younger patients whose chest walls are more flexible.
Hospital stays are comparable for both procedures. Most patients return to light daily activities within a few weeks, though full recovery, including return to contact sports and heavy lifting, typically takes several months. Both surgeries have high long-term success rates, and most patients report significant improvement in both appearance and exercise tolerance afterward.