What is pectus excavatum?
Commonly called "funnel chest," pectus excavatum is a depression or hollow caused when the sternum (breastbone) is abnormally pushed inward. The depression in the chest is due to abnormal growth of the cartilage that attaches the sternum to the ribs.
Because of the deep depression, the abdomen often protrudes and gives the appearance of a potbelly in younger children. If both sides of the breastbone are depressed in an equal fashion, the defect will appear symmetrical. However, in many cases, the chest wall appears asymmetric, with the left side of the chest being wider than the right side. In such cases, the sternum is abnormally rotated.
Pectus excavatum occurs in 1 in 500 to 1,000 children. It may be minimal, with only slight depression of the chest or it may be quite severe, causing compression of the heart and lungs and altering their functioning. The abnormality increases with age and often worsens during the growth spurts that occur during late childhood and adolescence. It stabilizes after skeletal growth is complete.
What causes pectus excavatum?
While the cause of this abnormality is unknown, the fact that it tends to occur in families suggests that genetics may play a role. Excessive growth and structural abnormalities of the cartilage (tough, connective tissue) of the ribs and breastbone are present in pectus excavatum.
Also, pectus excavatum is seen in some inherited connective tissue disorders such as Marfan syndrome, homocystinuria and Ehlers-Danlos syndrome.
What are the symptoms of pectus excavatum?
Although some children are asymptomatic (experience no symptoms), symptoms usually vary with the severity of the abnormality. Younger children are thus less symptomatic than older children.
- Children with less severe defects often have mild respiratory problems or frequent and prolonged colds.
- Children with moderate to severe pectus deformities often experience breathing difficulties upon exertion and decreased exercise tolerance due to impaired lung and/or heart function. Lung capacity is decreased and the filling capacity of the heart chambers is restricted due to compression from the sternum. These symptoms can be quite severe at times, thus limiting the child's activity level.
Growing adolescents may also experience chest pain in the area of rib cartilages.
How is pectus excavatum diagnosed?
Diagnostic imaging tests such as chest xray or computed tomography scan (CT) may be performed to define the anatomy of the chest.
An electrocardiogram (ECG or EKG) and an echocardiogram (echo)may be performed to determine the extent of cardiac compromise, if any. An ECG is a test that records the electrical activity of the heart, showing abnormal rhythms and detecting heart muscle stress. An echo is a procedure that uses sound waves to study the structures and function of the heart. Additionally, Pulmonary Function Tests (PFTs) may be performed. PFTs can help detect breathing problems that may be related to the pectus excavatum.
How is pectus excavatum treated?
Mild abnormalities occasionally correct themselves early in childhood. Children with moderate to severe abnormalities may require surgery, which is usually not performed in children younger than age 12.
Since children have softer cartilage and more flexible bones than adolescents, the operation is easier to perform on them and the cosmetic results are superior. Most operations are performed after the growth spurt or onset of puberty. If corrected at too early an age, future operations by be necessary.
Infants and very young children are usually not considered for operation unless very severe abnormalities (cardiac defect, severe problems with lungs or heart) or other illnesses necessitate earlier surgery.
Pectus excatvaum surgery
Minimally invasive technique or Nuss procedure is used to correct pectus excavatum. Occaisonally the Ravitch or open procedure is necessary. Both techniques generally improve chest appearance. They also improve rib and sternum configuration as well as cardiopulmonary (heart and lung) functioning.
Minimally Invasive Surgery (Nuss Procedure)
Minimally invasive surgical techniques have been used for more than a decade. With this approach, two small lateral incisions are made. A bar that has been shaped to the desired chest contour is inserted into and across the chest and positioned below the sternum. This is done using the guidance of an endoscope (instrument used to visualize the inside of the chest). The bar is held in place by sutures and by a small metal plate that prevents rotation of the bar as the chest is reshaped. This procedure is very similar to placing braces on teeth, which facilitates their correct realignment.
Length of hospital stay is usually 5 to 7 days. Postoperative epidural analgesia catheters or intravenous narcotics may be required for several days following surgery. Milder pain is managed with oral pain medication. Activity is slowly resumed, with limitations on exercise and sleeping positions until the bar is healed in place.
The bar is left in place for 2-4 years, allowing the chest to remold. The bar is then removed during outpatient surgery. The bar will be removed in the operating room after about 2-4 years. It may require an overnight stay for pain medication but most children go home the same day of the operation.
In our experience, short-term outcomes with minimally invasive surgery are at least comparable to outcomes with open surgery. They result in a better cosmetic outcome with less scarring (due to smaller incisions), good restoration of normal chest contour and good muscle function.
What can be expected following surgery?
Your activities will be restricted during the initial recovery period of 6-12 weeks. Patients are encouraged to exercise in order to improve overall chest growth and contour and to increase the strength of their chest muscles. You and your child will receive detailed discharge instructions on exercise, positioning and pain management prior to leaving the hospital.