A funnel chest(pectus excavatum) is a malformation of the ribcage. It appears as a funnel-shaped depression of the chest area backwards towards the spine. The sternum and the cartilage connections between the sternum and ribs (rib cartilage) are affected.
The funnel chest is the most common malformation of the human rib cage. It occurs with a frequency of around 0.1 to 2 percent. Boys are affected by this thoracic deformity about 3 times more frequently than girls.
Funnel chest in a man © jupiter8 | AdobeStock
The cause of this malformation has not yet been definitively clarified. However, there are indications that
- there is a weakness in the anterior chest wall or
- mechanical factors play a role in its development.
In addition, up to 40 percent of cases are familial. It is therefore assumed that genetic reasons are also partly responsible for the development of a funnel chest.
In addition, the funnel chest occurs more frequently in various syndromes, such as
- Marfan syndrome,
- Poland syndrome and
- fetal alcohol syndrome.
A funnel chest can usually be recognized immediately after birth. The malformation becomes more pronounced as the body continues to grow. As the ribcage is still elastic, the heart and lungs can adapt to the anatomical situation in the thorax. This is why children and adolescents often have no physical complaints.
With increasing age and degree of depression, however, physical complaints can occur. The misalignment of the ribs can be transferred to the spine and lead to poor posture.
The shoulders are then often tilted forward, the abdomen protrudes and the spine is curved backwards(kyphosis). As a result, the intervertebral discs are exposed to greater strain, which leads to back pain.
If there is increased pressure on the stomach due to the incorrect posture, heartburn can occur more frequently. Occasionally, funnel chest also causes symptoms such as
- shortness of breath,
- palpitations and
- rapid fatigue
occur. In most cases, however, lung function tests and heart examinations rarely reveal pathological findings.
As children and adolescents often suffer from the deformity, psychological abnormalities can develop. Some reject their body, do not do any sport and withdraw from their social environment.
For medical reasons, funnel chest surgery is therefore rarely indicated if there are no symptoms.
Funnel chest surgery may be necessary if the heart or lungs are severely displaced and physical symptoms occur.
General measures for the treatment of a funnel chest
Generally speaking, treatment in childhood is rather cautious. Funnel chest surgery is rarely indicated. Instead, the development of the funnel chest is monitored regularly.
Physiotherapy and posture training are also recommended. Adolescents and adults prevent incorrect loading of the intervertebral discs by training their back muscles. Muscle and fitness training can also be useful.
Funnel chest correction using a suction cup
Instead of a funnel chest operation, a suction cup treatment can also be considered.
A suction cup specially adapted to the patient's anatomy slowly pulls the ribcage upwards. The first application of the suction cup is usually carried out on an outpatient basis in a clinic so that the doctor can check that it is being applied correctly.
The duration of treatment depends on the extent and general condition of the patient. The suction cup may have to be used up to several times a day for up to several hours over two to three years. Long-term results are still pending, but the initial results are promising.
Funnel chest surgery is necessary for
- Restrictions in physical functions (such as breathing or heart function) or
- psychological stress due to the funnel chest.
Today, the decision to have funnel chest surgery is usually made for psychological and/or cosmetic reasons.
Funnel chest surgery is only advised in rare cases in children.
Adolescents and adults often suffer from psychological and cosmetic stress. This is why they usually express a desire for funnel chest correction themselves.
The aim of funnel chest surgery is to achieve the most complete funnel chest correction possible while avoiding large surgical scars. For this reason, minimally invasive procedures are increasingly being used today instead of conventional open procedures.
The main procedures used are
- minimally invasive funnel chest surgery according to Nuss (MIRPE) and
- sternochondroplasty (Erlangen funnel chest operation).
The methods of funnel chest surgery according to Ravitch or Rehbein, which were previously performed more frequently, are increasingly being abandoned. These procedures are very complex and very stressful for the patient. From a cosmetic point of view, an unfavorable incision is required. This is followed by a hospital stay of 14 to 21 days.
Preliminary examinations in preparation for funnel chest surgery
The full extent of the funnel chest can only be visualized using imaging techniques.
Pulmonary function tests and ECG or echocardiography are used to look for cardiac dysfunction and impaired breathing.
The examinations are usually carried out at the clinics that also perform funnel chest surgery. The examination results are then sent to the appropriate specialist clinic in preparation for funnel chest surgery.
X-ray examination (CT scan)
Important imaging procedures are the classic X-ray or, better still, computer tomography (CT). A CT scan provides a more detailed image than an X-ray. Both procedures can show the bones, including the ribs and sternum.
Bones and other dense tissue absorb X-rays more strongly than less dense tissue (e.g. the skin). This allows the ribs and sternum to be recognized with the formation of the kink and the exact extent of the funnel chest to be determined.
The X-ray examination is used
- in preparation for a funnel chest correction and
- to rule out other diseases (e.g. of the spine).
is used.
An X-ray of the chest is an important tool in the assessment of a funnel chest © jupiter8 | AdobeStock
Magnetic resonance imaging (MRI)
With the help of magnetic resonance imaging, high-resolution cross-sectional images can be displayed in detail. In contrast to CT, it also shows the soft tissue.
MRI can be used to determine the extent of the funnel chest, such as the funnel depth and diameter.
In contrast to an X-ray examination, there is no radiation exposure with an MRI.
Haller index
The extent of a funnel chest can be objectified on the basis of the funnel depth. The Haller index
- the transverse diameter of the ribcage and
- the distance between the deepest point of the funnel and the spine.
in relation to each other.
If the Haller index is 3.2 or higher, a recommendation for funnel chest surgery is often made.
Pulmonary function test
The pulmonary function test provides information on the extent to which lung function is impaired as a result of a funnel chest.
For example
- the lung volume,
- the expiratory reserve volume (ERV),
- the inspiratory vital capacity (IVC) and
- the forced vital capacity (FVC)
are determined. This allows the extent of any functional limitations to be determined and the need for funnel chest correction to be assessed.
A lung function test can allow conclusions to be drawn about the extent of the funnel chest © mjowra | AdobeStock
Echocardiography
Echocardiography can be used to assess any impairment of the heart valves and certain heart functions.
This can also be used to assess the need for funnel chest correction.
Exercise ECG
A funnel chest can also lead to impaired cardiovascular function (e.g. cardiac arrhythmia). An exercise ECG can assess cardiac function during physical activity.
This can also help to assess the need for funnel chest surgery.
Minimally invasive funnel chest surgery according to Nuss (MIRPE)
In Nuss funnel chest correction, only two small incisions are made under the armpit on the lateral chest wall. They are not cosmetically disruptive later on.
Through these incisions, a pre-bent metal bar is inserted under the breastbone at the level of the funnel. The metal bar is adapted to the patient's anatomy in advance. The surgeon checks that it fits correctly using a video camera (thoracoscopy).
The bar, which is made of steel or titanium for allergy sufferers, is fixed to the side, leaving the sternum itself intact. This pushes the sunken sternum and the affected ribs with the deformed rib cartilage outwards again.
In some cases, two or even three metal brackets are required.
The funnel chest correction is performed under general anesthesia and takes about 50 minutes. The two small side incisions heal quickly without any annoying scarring. After the funnel chest operation, the external cosmetic success is immediately visible and the chest has a "normal" shape.
Complications related to the operation are also rare. The patient can therefore leave the hospital after just a few days.
After around three months, the patient can resume a completely normal life with all their usual activities.
After two to three years, the metal stirrups are surgically removed. In older patients, it may be necessary to leave the metal stirrups in the body for longer.
As the chest wall still needs to be elastic for this type of funnel chest correction, it is particularly suitable for younger patients.
Very good results can be achieved with this type of funnel chest correction, especially with symmetrically shaped funnel chests. The best time for funnel chest surgery according to Nuss is at the end of puberty, although later procedures are also possible.
Minimally invasive funnel chest surgery according to Rokitansky
A further development of the Nuss funnel chest surgery is the minimally invasive Rokitansky funnel chest correction.
This is characterized, among other things, by
- Notching of the sternum,
- thoracoscopic slitting of the costal cartilage and
- the use of a metal frame consisting of only one piece,
is characterized. This prevents metal abrasion in the body.
Open funnel chest surgery: sternochondroplasty (Erlangen funnel chest correction)
The Erlangen funnel chest operation is also known as the minimalized Erlangen correction method (MEK). It is based on the Ravitch/Rehbein/Wernicke methods. In these methods, the rib cage is opened through a vertical incision several centimeters long in men or horizontal in women.
The deformed ribs are then separated from the sternum and the cartilage on the deformed ribs is removed. After the sternum has been sawed, it is lifted and fixed in place with metal brackets. The thorax is then closed again.
In the funnel chest operation, which was further developed in Erlangen, the ribs are not completely removed. Instead, they are only notched at the base of the sternum. The sternum is then stabilized in a raised state. For this purpose, one or two metal brackets are inserted through a small incision in the lateral chest wall. The metal stirrups can be surgically removed after just one year.
The Erlangen funnel chest correction is a relatively gentle surgical procedure. Similar to the Nuss funnel chest operation, the patient can leave the clinic after just a few days.
It can be used for both symmetrical and asymmetrical deformities and is suitable for all age groups (including the elderly).
After several decades of use, the Erlangen funnel chest correction can demonstrate very good long-term results.
Like any other surgical procedure, funnel chest surgery involves certain risks. Wound healing disorders can occur as a result of the mechanical procedure or an infection in the wound.
Very rarely, severe infections and allergic reactions to the metal stirrups can occur. These must then be removed prematurely. If allergies (e.g. a nickel allergy) are known, special titanium stirrups can be used.
Any pain that may occur after the operation can be treated efficiently. As a preventative measure, anesthetists can insert a peridural catheter (PDK) during funnel chest surgery. This can be used to manually control the activity of the nerves in the thoracic region.
This allows pain treatment to be controlled after the funnel chest correction and complete freedom from pain to be achieved.
Depending on the funnel chest surgery performed, a hospital stay of around 6 to 11 days, sometimes up to several weeks, may be required. Mobilization usually begins on the first day after funnel chest surgery. However, strong rotational movements of the upper body should be avoided for the first 8 to 12 weeks after funnel chest surgery.
The corrected funnel chest should be checked at regular intervals by X-ray examination. In addition, the muscles should be strengthened under physiotherapeutic guidance. Normal exercise of the upper body is usually possible after three months. If heavy physical exertion is planned, the stability of the funnel chest correction should be checked beforehand.
Depending on the funnel chest operation, the metal stirrup or stirrups are either
- after just one year (Erlangen funnel chest correction) or
- after around three to four years (Nuss funnel chest correction)
are removed by means of a final surgical procedure.
