Definition and epidemiology
Pectus excavatum is a developmental deformity of the anterior chest wall characterized by posterior depression of the sternum (usually the lower two-thirds, including the xiphoid region) and the adjacent costal cartilages, producing a concave or "funnel-shaped" chest.
- Most common congenital chest wall deformity, accounting for roughly 90% of chest wall anomalies
- Estimated prevalence around 1 in 300 to 1 in 1000 births
- Male-to-female ratio approximately 4:1
- Often present at birth or in early infancy but becomes more noticeable and symptomatic during the adolescent growth spurt due to rapid cartilage growth
- Family history is present in roughly a third of cases, suggesting a genetic contribution
- Pectus excavatum = posterior sternal depression; most common congenital chest wall deformity, male predominance
- Strongly associated with Marfan syndrome and Ehlers-Danlos syndrome — screen for connective tissue disease
- Haller index >3.25 on CT is the key quantitative threshold for surgical candidacy
- Severe cases can compress the right ventricle and reduce exercise tolerance, not usually cause resting symptoms
- Vacuum bell therapy works best in young patients with flexible, pliable cartilage
- Nuss procedure = minimally invasive bar placement; Ravitch procedure = open cartilage resection
- Echocardiogram is used to assess cardiac compression/displacement and screen for mitral valve prolapse or aortic root disease
- Psychosocial distress alone is an accepted indication for surgical correction
Etiology and risk factors
The exact cause is unknown, but the leading theory involves abnormal or overgrowth of the costal cartilages, which pushes the sternum inward.
Associated conditions
- Marfan syndrome — tall stature, arachnodactyly, lens dislocation, aortic root dilation
- Ehlers-Danlos syndrome — joint hypermobility, skin hyperextensibility
- Scoliosis — found in a substantial minority of patients
- Congenital heart disease (less common association)
- Mucopolysaccharidoses and other skeletal dysplasias (rarer)
Risk factors
- Family history of pectus deformity
- Male sex
- Rapid growth phases (puberty) that unmask or worsen the deformity
Because of the connective tissue disease association, any patient presenting with pectus excavatum should be screened clinically for features of Marfan syndrome, particularly if there is tall stature or a family history of aortic disease.
Pathophysiology
The prevailing hypothesis is that overgrowth or structural abnormality of the costal cartilages (ribs 4-7) causes them to buckle, drawing the sternum posteriorly. Unlike pectus carinatum (outward protrusion), the deformity here is inward.
- Progressive cartilage overgrowth during childhood and adolescence can worsen the depression over time
- Severe depression can displace the heart leftward and compress the right ventricle and right ventricular outflow tract
- Compression may reduce cardiac filling and stroke volume during exercise, and can mildly compress the lungs, limiting total lung capacity
- Most patients remain asymptomatic despite the anatomic abnormality; symptoms when present are usually exertional, reflecting mild cardiopulmonary restriction rather than fixed structural disease
Clinical features
- Visible concave depression of the sternum, often most pronounced at the xiphoid/lower sternal region
- Usually painless and cosmetic in mild cases
- In moderate-to-severe cases: exertional dyspnea, decreased exercise tolerance, chest pain
- Occasional palpitations (related to cardiac compression/displacement)
- Psychosocial distress and body image concerns, especially in adolescents, which is a major driver of treatment-seeking
- Possible audible or palpable mid-systolic click or murmur if mitral valve prolapse coexists (seen more often with connective tissue disease)
- Look for stigmata of Marfan syndrome (arm span > height, arachnodactyly, high-arched palate) on exam
Diagnosis
Diagnosis is primarily clinical, based on inspection of the chest wall. Imaging is used to quantify severity and assess cardiopulmonary impact, not to make the diagnosis itself.
Workup
- Clinical photographs and physical exam — document severity and symmetry
- CT chest (or MRI to avoid radiation in children) — calculate the Haller index (ratio of the transverse diameter of the chest to the anteroposterior diameter at the point of maximum depression)
- Echocardiogram — assess for cardiac compression, displacement, mitral valve prolapse, and screen for aortic root dilation if Marfan features present
- Pulmonary function tests — may show mild restrictive pattern in moderate-severe cases
- Cardiopulmonary exercise testing — used in some centers to objectively document functional limitation
Haller index interpretation
| Haller Index | Severity |
|---|---|
| < 3.25 | Normal/mild |
| ≥ 3.25 | Severe, generally considered surgical threshold |
A Haller index above 3.25, combined with symptoms, cardiac compression, or significant psychosocial impact, supports surgical referral.
Differential diagnosis
- Pectus carinatum — outward protrusion of the sternum rather than depression
- Poland syndrome — pectus deformity with absence of the pectoralis muscle and ipsilateral hand anomalies
- Postural chest asymmetry — mimics mild pectus but lacks fixed structural depression
- Rickets-related chest deformity — associated with other skeletal findings of vitamin D deficiency
- Scoliosis-associated chest wall asymmetry — asymmetric chest contour from spinal curvature rather than true sternal depression
Management
Management depends on severity, symptoms, and patient age, and follows a stepwise approach consistent with major pediatric surgery society guidance (e.g., American Pediatric Surgical Association).
Mild, asymptomatic disease
- Observation and reassurance
- Physical therapy/postural exercises in some practices, though evidence is limited
Nonsurgical options
- Vacuum bell therapy — external suction device worn over the chest to gradually lift the sternum; most effective in younger patients with flexible cartilage and mild-to-moderate deformity; requires prolonged daily use over months to years
Surgical options (for Haller index ≥3.25, symptomatic disease, cardiopulmonary compromise, or significant psychosocial distress)
- Nuss procedure (minimally invasive repair) — placement of a convex metal bar beneath the sternum via small lateral incisions, thoracoscopically guided, to push the sternum outward; bar is removed after roughly 2-3 years
- Ravitch procedure (open repair) — resection of abnormal costal cartilages with sternal osteotomy and fixation; more invasive, used for complex, asymmetric, or recurrent cases, or in older patients with rigid cartilage
Timing: surgical correction is generally preferred during adolescence (roughly ages 12-18) when the chest wall is still pliable but growth is sufficient to tolerate the procedure, though both techniques can be performed in adults.
All patients with suspected Marfan syndrome should be referred for genetics evaluation and surveillance echocardiography regardless of pectus management.
Complications and prognosis
- Most patients have an excellent prognosis, especially with mild deformity and no cardiopulmonary involvement
- Untreated severe cases can cause progressive exertional limitation and cardiac displacement
- Surgical complications (Nuss/Ravitch): bar displacement or migration, pneumothorax, pleural effusion, infection, recurrence (more common with Ravitch in young children), and chronic pain
- Psychosocial outcomes (self-esteem, body image) often improve significantly after correction, which is itself a recognized indication for surgery
- Recurrence after surgery is uncommon but possible, particularly if performed before skeletal maturity in the Ravitch technique
HALLER = High Anteroposterior:Lateral Ratio = surgical candidate when index > 3.25
Practice questions
1. A 15-year-old boy is brought in for evaluation of a sunken chest wall that has become more noticeable over the past year during his growth spurt. He reports mild shortness of breath with running during soccer practice but is otherwise healthy. On exam there is a symmetric depression of the lower sternum. A CT chest is ordered. Which of the following findings would be the strongest indication for surgical correction?
2. A 17-year-old girl with pectus excavatum is noted on exam to be unusually tall for her family, with long fingers and a high-arched palate. Which additional study is most important to obtain given these findings?
3. A 13-year-old boy with a mild, flexible pectus excavatum deformity and no symptoms is being evaluated for treatment options. His cartilage is still pliable and he wants to avoid surgery if possible. Which treatment is most appropriate as a first-line, nonsurgical option?
Frequently asked questions
What causes pectus excavatum?
The exact cause is unknown, but it is believed to result from abnormal overgrowth of the costal cartilages that pushes the sternum inward. It often runs in families and is strongly associated with connective tissue disorders such as Marfan syndrome and Ehlers-Danlos syndrome. Rapid cartilage growth during adolescence commonly worsens an existing mild deformity.
What are the first signs of pectus excavatum?
The first sign is usually a visible sunken or concave area of the lower chest and sternum, often noticed in infancy or early childhood. In many cases it becomes more pronounced during the adolescent growth spurt. Most children have no symptoms beyond the cosmetic appearance; exertional fatigue or chest discomfort suggests a more severe deformity.
How is pectus excavatum diagnosed?
Diagnosis is made by physical examination of the chest wall appearance. A CT or MRI scan is then used to calculate the Haller index, which measures the severity of the depression and helps determine if surgery is needed. An echocardiogram and pulmonary function tests may be added to check for cardiac or lung compression in moderate-to-severe cases.
Is pectus excavatum curable?
Yes, it can be effectively corrected, though mild cases often do not require any treatment at all. Nonsurgical vacuum bell therapy can improve mild-to-moderate deformities in younger patients, while surgery (Nuss or Ravitch procedure) provides durable correction for more severe or symptomatic cases. Many patients choose correction for cosmetic and psychological reasons even without physical symptoms.
Pectus excavatum vs pectus carinatum — what is the difference?
Pectus excavatum is an inward depression of the sternum, giving a sunken chest appearance, while pectus carinatum is an outward protrusion of the sternum, giving a pigeon-chest appearance. Excavatum is more common and can compress the heart and lungs, while carinatum is almost always purely cosmetic. Both are congenital chest wall deformities involving abnormal costal cartilage growth.
Related conditions and differentials
Sources and further reading
StatPearls (NCBI Bookshelf)MedlinePlusWHO ICD-10: Q67.6
Educational content for medical students, prepared by the WhiteCoat Pro editorial team with AI assistance; every page is reviewed by a second AI model for factual errors. It is not medical advice and does not replace the product label, local guidelines or a clinician.