Pectus carinatum, keel), also called pigeon chest, is a deformity of the chest characterized
by a protrusion of the sternum and ribs.
It is distinct from the related deformity pectus excavatum.
Causes Pectus carinatum is an overgrowth of cartilage
causing the sternum to protrude forward.
It primarily occurs among four different patient groups, and males are more frequently affected
than females.
Most commonly, pectus carinatum develops in 11-to-14-year-old pubertal males undergoing
a growth spurt.
Some parents report that their child's pectus carinatum seemingly popped up overnight.
Second most common is the presence of pectus carinatum at or shortly after birth.
The condition may be evident in newborns as a rounded anterior chest wall.
As the child reaches age 2 or 3 years of age, the outward sternal protrusion becomes more
pronounced.
Least common is a pectus carinatum deformity following open-heart surgery or in children
with poorly controlled bronchial asthma.
Pectus carinatum is generally a solitary, non-syndromic abnormality.
However, the condition may be present in association with other syndromes: Turner syndrome, Noonan
syndrome, Marfan syndrome, Ehlers-Danlos syndrome, Morquio syndrome, trisomy 18, trisomy 21,
homocystinuria, osteogenesis imperfecta, multiple lentigines syndrome, Sly syndrome, and scoliosis.
In about 25% of cases of pectus carinatum, the patient has a family member with the condition.
Epidemiology Pectus deformities are common; about 1 in
400 people have a pectus disorder.
Pectus carinatum is rarer than pectus excavatum, another pectus disorder, occurring in only
about 20% of people with pectus deformities.
About four out of five patients are males.
Symptoms People with pectus carinatum usually develop
normal hearts and lungs, but the deformity may prevent these from functioning optimally.
In moderate to severe cases of pectus carinatum, the chest wall is rigidly held in an outward
position.
Thus, respirations are inefficient and the individual needs to use the accessory muscles
for respiration, rather than normal chest muscles, during strenuous exercise.
This negatively affects gas exchange and causes a decrease in stamina.
Children with pectus deformities often tire sooner than their peers, due to shortness
of breath and fatigue.
Commonly concurrent is mild to moderate asthma.
Some children with pectus carinatum also have scoliosis.
Some have mitral valve prolapse, a condition in which the heart mitral valve functions
abnormally.
Connective tissue disorders involving structural abnormalities of the major blood vessels and
heart valves are also seen.
Although rarely seen, some children have other connective tissue disorders, including arthritis,
visual impairment and healing impairment.
Apart from the possible physiologic consequences, pectus deformities can have a significant
psychologic impact.
Some people, especially those with milder cases, live happily with pectus carinatum.
For others, though, the shape of the chest can damage their self-image and confidence,
possibly disrupting social connections and causing them to feel uncomfortable throughout
adolescence and adulthood.
As the child grows older, especially if male, bodybuilding techniques may be useful for
balancing visual impact.
Prognosis Pectus deformities usually become more severe
during adolescent growth years and may worsen throughout adult life.
The secondary effects, such as scoliosis and cardiovascular and pulmonary conditions, may
worsen with advancing age.
Body building exercises will not alter the ribs and cartilage of the chest wall, and
are generally considered not harmful.
Most insurance companies no longer consider chest wall deformities like pectus carinatum
to be purely cosmetic conditions.
While the psychologic impact of any deformity is real and must be addressed, the physiological
concerns must take precedence.
The possibility of lifelong cardiopulmonary difficulties is serious enough to warrant
a visit to a thoracic surgeon.
Treatment External bracing technique
In children, teenagers, and young adults who have pectus carinatum and are motivated to
avoid surgery, the use of a customized chest-wall brace that applies direct pressure on the
protruding area of the chest produces excellent outcomes.
Willingness to wear the brace as required is essential for the success of this treatment
approach.
The brace works in much the same way as orthodontics.
The brace consists of front and back compression plates that are anchored to aluminum bars.
These bars are bound together by a tightening mechanism which varies from brace to brace.
This device is easily hidden under clothing and must be worn from 14 to 24 hours a day.
The wearing time varies with each brace manufacturer and the managing physicians protocol, which
could be based on the severity of the carinatum deformity and if it is symmetric or asymmetric.
Depending on the manufacturer and/or the patient's preference, the brace may be worn on the skin
or it may be worn over a body 'sock' or sleeve called a Bracemate, specifically designed
to be worn under braces.
A physician or orthotist or brace manufacturer's representative can show how to check to see
if the brace is in correct position on the chest.
Bracing is becoming more popular over surgery for pectus carinatum, mostly because it eliminates
the risks that accompany surgery.
The prescribing of bracing as a treatment for pectus carinatum has 'trickled down' from
both paediatric and thoracic surgeons to the family physician and pediatricians again due
to its lower risks and well-documented very high success results.
Regular supervision during the bracing period is required for optimal results.
Adjustments may be needed to the brace as the child grows and the pectus improves.
If the person with PC is not treated with a brace by the end of puberty, the brace technique
is not an option, as the shape of the ribcage and sternum are set for the rest of their
lives.
Surgical For patients with severe pectus carinatum,
surgery may be necessary.
However bracing could and may still be the first line of treatment.
Some severe cases treated with bracing may result in just enough improvement that patient
is happy with the outcome and may not want surgery afterwards.
If bracing should fail for whatever reason then surgery would be the next step.
The two most common procedures are the Ravitch technique and the Reverse Nuss procedure.
The Nuss was developed by Donald Nuss at the Children's Hospital of the King's Daughters
in Norfolk, Va.
The Nuss is primarily used for Pectus Excavatum, but has recently been revised for use in some
cases of PC, primarily when the deformity is symmetrical.
Other options After adolescence, some men and women use
bodybuilding as a means to hide their deformity.
Some women find that their breasts, if large enough, serve the same purpose.
Some plastic surgeons perform breast augmentation to disguise mild to moderate cases in women.
Bodybuilding is suggested for people with symmetrical pectus carinatum.
See also Pectus excavatum
References