A dent in the center of your rib cage is almost always a condition called pectus excavatum, where the breastbone (sternum) curves inward instead of sitting flat. It’s the most common chest wall deformity, affecting roughly 1 in 300 to 1 in 1000 people, and it’s five times more common in males. Some people notice it from childhood, while others don’t pay attention until their teenage years or adulthood, when growth spurts can make the indentation more obvious.
What Causes the Dent
Pectus excavatum develops because the cartilage connecting your ribs to your breastbone grows abnormally, pulling the sternum inward. This creates a visible depression in the chest that can range from a shallow dip you barely notice to a deep funnel shape. The condition is present from birth in most cases, though it often becomes more pronounced during the adolescent growth spurt.
The underlying issue appears to be rooted in connective tissue. Studies of the cartilage in affected patients consistently show structural abnormalities, and nearly all people with pectus excavatum display some degree of connective tissue irregularity. This is why the condition frequently shows up alongside connective tissue disorders like Marfan syndrome (roughly half of people with Marfan have a concave chest) and Ehlers-Danlos syndrome. If you have a family history of either condition, or if you’re unusually tall and flexible with long limbs, that connection is worth mentioning to a doctor.
Less commonly, a dent in the rib cage can result from a direct injury. A fractured sternum or broken ribs that heal improperly can leave an indentation. Severe scoliosis, particularly the kind that develops after spinal trauma, can also distort the shape of the rib cage over time. If your dent appeared after an injury rather than something you’ve had most of your life, the cause is likely traumatic rather than congenital.
When a Dent Is More Than Cosmetic
Many people with a mild dent have no symptoms at all. But when the indentation is deep enough, the breastbone can press against the heart and lungs, creating real functional problems. The sternum in these cases essentially stays locked in position during breathing instead of moving outward, forcing the body to compensate by relying more heavily on abdominal breathing. This limits how much air you can take in with each breath.
In a study of more than 1,500 surgical patients with severe pectus excavatum, lung function values were shifted significantly lower than normal across the board. People with the deepest indentations were four times more likely to show a restrictive breathing pattern, meaning their lungs simply couldn’t expand fully. Exercise capacity suffers too: oxygen uptake during exertion tends to be reduced, and the heart has to work harder to pump the same amount of blood when it’s being physically compressed.
Symptoms to watch for include:
- Shortness of breath during physical activity that seems disproportionate to your fitness level
- Chest pain or pressure, particularly during exercise
- Heart palpitations, including a racing, fluttering, or pounding sensation
- Declining endurance that gets worse over time rather than improving with training
If the dent is getting deeper over time or any of these symptoms are present, imaging is the next step. A CT scan measures the severity using something called the Haller index, which compares the width of your chest to the distance between your spine and the deepest point of the dent. A normal chest scores around 2.5. Anything above 3.25 is considered moderate to severe and puts surgical correction on the table as a serious option.
Non-Surgical Options
For mild to moderate cases, a device called a vacuum bell can gradually lift the sternum outward over time. It works like a large suction cup placed over the chest, creating negative pressure that pulls the breastbone forward. The catch is consistency: you need to use it for at least four hours a day, for a year or longer, to see stable results. Adults typically need to double that usage time.
The ramp-up is gradual. Most protocols start with 30 minutes twice a day during the first week, increasing to about two and a half hours daily by week five. Each session shouldn’t exceed two hours, with short breaks in between.
Results vary considerably. In one North American study of 115 patients, about 20% achieved excellent correction and another 17% saw good improvement. The best predictors of success were starting before age 11, having a shallow initial depth (less than 1.5 centimeters), maintaining consistent use for over 12 months, and having a flexible chest wall. For older patients or deeper deformities, the vacuum bell is less likely to produce dramatic results, though it can still offer some improvement.
Surgical Correction
Two main surgical approaches exist for pectus excavatum that’s severe enough to cause symptoms or significant cosmetic concern.
The Nuss procedure is minimally invasive. A curved metal bar is inserted beneath the sternum through small incisions on each side of the chest. The bar pushes the breastbone outward into a normal position, where it stays for two to three years while the chest wall remodels around it. The bar is then removed in a second, shorter procedure. Operating time is significantly shorter than the alternative, and blood loss is lower.
The Ravitch procedure is an open surgery. The surgeon removes sections of the abnormal cartilage, cuts the sternum to reposition it, and stabilizes it with a support bar. It’s a more extensive operation, but it gives the surgeon direct control over reshaping the chest wall.
For children and teenagers, complication rates between the two procedures are comparable. Reoperation rates are similar (around 6% for both), and outcomes are generally good with either approach. The picture changes for adults. In adult patients, the Ravitch procedure tends to have lower overall complication rates and a significantly lower reoperation rate (about 5% compared to nearly 29% for the Nuss procedure). Bar displacement is also more common with the Nuss approach, occurring at roughly four times the rate seen with the Ravitch technique.
The good news on the functional side: after surgical repair, lung function improves by approximately one standard deviation across the population. In patients who completed exercise testing before and after surgery, maximum oxygen uptake increased by 10% and the heart’s pumping efficiency improved by 20%. For people who were limited by their condition, that translates to a noticeable difference in everyday activity and exercise tolerance.
Dents That Aren’t Pectus Excavatum
Not every rib cage dent is pectus excavatum. A small, localized indentation on one side of the rib cage, rather than a symmetrical depression of the sternum, could be from an old rib fracture you don’t remember, particularly if it happened in childhood. Costochondritis, an inflammation of the cartilage where ribs attach to the breastbone, can sometimes create the appearance of unevenness in the chest wall, though it’s more associated with pain and swelling than a true structural dent.
If the indentation is at the very bottom of your sternum, right where it ends, what you’re feeling may simply be the xiphoid process, a small piece of cartilage at the lower tip of the breastbone. In some people it angles inward naturally, and losing body fat or weight can make it more noticeable. This is a normal anatomical variation, not a deformity.