What is pectus excavatum? Symptoms, causes and types
By Javier Santana, founder of Pectus Academy · Updated October 2026
Short answer: pectus excavatum, also called sunken chest or funnel chest, is a breastbone that sinks into the chest. It occurs in 1 in 300 to 1 in 1,000 births and is about five times more common in males. In many cases it only changes how the chest looks; in severe cases it can press on the heart and lungs.
What exactly is it?
The breastbone is the flat bone in the middle of the chest, joined to the ribs by cartilage. In pectus excavatum, the middle and lower part of the breastbone and that cartilage are pushed back toward the spine. The dip is usually asymmetric and tends to sit to the right.
Who gets it, and when does it show?
- How common: 1 in 300 to 1 in 1,000 births, about five times more often in males.
- When it shows: most cases become visible in the first year of life; the most marked ones, at birth.
- How it changes: it usually gets more pronounced during the growth spurt of puberty and can keep doing so into adulthood.
- Family: 35% to 40% of cases have a family history.
Why does it happen?
The exact cause is unknown. The proposed explanations are a breastbone that is weaker or more flexible than normal, excessive rib growth and a failure in how the bony chest develops. The cartilage joining the ribs to the breastbone is thought to grow irregularly, with a genetic component.
It is more common in people with connective tissue conditions such as Marfan syndrome, Ehlers-Danlos syndrome or osteogenesis imperfecta, and with Noonan and Turner syndromes. It also often appears alongside scoliosis and kyphosis.
The sources we consulted do not attribute it to posture: a hunched back is listed among the consequences, not the causes.
What symptoms does it cause?
Many people have none. When there are symptoms, those described are:
- Shortness of breath or extreme tiredness during physical activity.
- Loss of endurance that gets worse over time.
- Chest pain.
- A rapid heartbeat or palpitations.
- Wheezing during exercise.
- Dizziness or fainting.
- Frequent upper respiratory infections.
- Distress about how the chest looks.
When should you see a doctor?
If you have any of those symptoms, especially if they are getting worse, or if the dip is getting deeper. You can start with your family doctor or pediatrician.
What shapes does it take?
A CT study of 283 patients aged 4 to 30 classified them like this:
| Shape | What it looks like | How common |
|---|---|---|
| Cup-shaped | A localized, deep dip | 67% |
| Saucer-shaped | A wide, shallow dip | 21% |
| Trench-like | A long dip that extends toward the upper chest | 10% |
| Mixed (Currarino-Silverman) | A sunken area combined with a protruding one | 1% |
In 80% the deepest point sat to the right of the midline. These were marked cases (mean Haller index of 4.9), so the proportions may be different in mild ones.
How is it diagnosed?
A physical exam is sometimes enough for the diagnosis. To measure severity, doctors use a CT scan, which gives the Haller index, an echocardiogram, lung function tests and an exercise test. We explain this in mild vs severe pectus excavatum.
Is it serious?
For many people, not physically: many children with pectus have a normal, active childhood and a healthy life without treatment. In severe cases the breastbone can stop the lungs from expanding fully and squeeze the heart.
The non-physical side counts too: the effect on body image has been measured in studies.
What are the options?
- Observation: for mild cases without symptoms.
- Posture, breathing and exercise: they can change how the chest looks, not where the breastbone sits. See pectus excavatum exercises.
- Vacuum bell: it reduces the dip in some patients, mostly young ones. See vacuum bell for pectus excavatum.
- Surgery: for severe cases or those with symptoms. See pectus excavatum surgery.
What we know and what we don't
What we know
- It runs in families: 35% to 40% of cases have a family history.
- It usually gets more pronounced at puberty.
- Many people have no physical symptoms.
What we don't know
- The exact cause.
- Which cases will get deeper and which won't: we have not found a reliable way to predict it.
Where to go next
For the full picture, read can you fix pectus excavatum without surgery? To start with the lowest-risk step, download the free guide to the 4 posture mistakes.
This content is educational and does not replace the advice of a healthcare professional. We do not promise a specific result.
Sources
- Sharma G, Carter YM. Pectus Excavatum. StatPearls, updated February 15, 2026. ncbi.nlm.nih.gov/books/NBK430918
- Mayo Clinic. Pectus excavatum: symptoms and causes, updated March 14, 2025. mayoclinic.org
- Mayo Clinic. Pectus excavatum: diagnosis and treatment, updated March 14, 2025. mayoclinic.org
- Kelly RE Jr, Quinn A, Varela P, Redlinger RE, Nuss D. Dysmorphology of Chest Wall Deformities: Frequency Distribution of Subtypes of Typical Pectus Excavatum and Rare Subtypes. Archivos de Bronconeumología, 2013;49:196-200. archbronconeumol.org
- Seattle Children's Hospital. Pectus Excavatum. seattlechildrens.org
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