Funnel chest refers to a depression of the sternum and rib cartilage, with the chest wall protruding posteriorly into the chest cavity, seen at birth, but more often in adolescents during the rapid growth period.
History
Funnel chest has been recognized in ancient times, as early as the 16th century, when Johan Schenck (1531-1590) collected literature on the subject. In 1594 Bauhinus described in his classic treatise the clinical features of a patient with a severe thoracic deformity with dyspnea and paroxysmal cough caused by pulmonary compression.
The individual genetic quality of thoracic deformities was first noted in 1820 by Coulson, who described a family in which all three brothers suffered from funnel chest. In 1872 Williams described a 17-year-old patient with a funnel chest whose father and brother also had the disease at the same time.
A large number of cases were reported in the 19th century, with five cases reported by W. Ebstein in 1882, summarizing their clinical features. Treatment during that period was limited to “fresh air, breathing exercises, aerobic activity and lateral pressure”. Surgeons also learned how to prevent lung collapse after intraoperative opening of the thorax.
Until the early 20th century, the chest was off-limits for surgery. The first attempt to surgically correct a funnel chest was an experimental operation performed by Meyer in Germany in 1911. He removed the 2nd and 3rd ribs of cartilage on the right side, but the chest wall deformity did not improve.
In 1913, Sauerbruch, one of the pioneers of thoracic surgery, invented a negative pressure chamber for thoracic surgery that met with some success through a more invasive approach. He removed a portion of the anterior chest wall, including the cartilage of the left 5th-9th ribs and an attached section of the sternum. Prior to surgery, the patient was unable to participate in any activity due to severe dyspnea and palpitations (which were present at rest) and was unable to work in his father’s watch factory. After the operation, although the heart was visible pulsating under the muscular flap, the patient was able to participate in work without respiratory distress and was married three years later.
In the 1920s, Sauerbruch performed the first chest wall fixation surgery, severing the bilateral rib cartilage and sternum, a method that was later developed by Ravitch more than 20 years later. sauerbruch advocated the use of external traction to keep the sternum in its normal position for 6 weeks after surgery to prevent recurrence. This technique was quickly adopted by European surgeons and soon became widely used in the United States.
In 1939, Ochsner and DeBakey published their surgical experience and reviewed the entire funnel chest literature, briefly depicting the various surgical approaches in lines. In the same year, LincolnBrown also published their experience with two surgeries and reviewed the literature, specifically mentioning the etiology of funnel chest, proposing the theory that shortening of the diaphragmatic ligament and pulling of the diaphragm caused the sternal subluxation. Although thoracoscopy has disproved this theory, there are some who are convinced of it to this day.
Ravitch at Johns Hopkins Hospital was convinced of this theory after seeing Brown’s article and advocated a more complete freeing of the sternum, severing all connections to the sternum, including the intercostal vascular nerve bundle, rectus abdominis, and diaphragm, as well as removing the saber process. in 1948, he published his experience with eight cases in which this radically modified procedure was used to remove bilateral rib cartilage and amputate the sternum. Because the sternum was severed and loosened from the surrounding connecting tissue, Ravitch believed that the sternum would not sink back into the thoracic cavity, so external traction was removed.
However, this modified surgical approach had an increased recurrence rate due to the lack of external traction. Based on this, Dorner introduced the concept of internal support in 1950, and in 1956 Wallgren and Sulamaa introduced the method of internal support with a slightly curved stainless steel plate. The stainless steel plate was fixed on both sides by passing through the caudal end of the sternum, connecting the sternum to the space between the ribs.
In 1961, Adkins and Blades took the internal bracing method one step further by using a straight stainless steel plate to pass behind the sternum rather than through it. This approach to thoracic deformity correction became the standard procedure for patients of all ages for the next 40 years. Many other materials have since been reported to be effective: titanium plates, Dacron vascular graft support material, gull-winged autologous material repairs, bioresorbable woven sheets, and posterior sternal mesh bands. Plastic surgeons have also treated funnel chests by implanting silicone bags within the depressions, which restores the appearance of the thorax but does not change the shape of the thorax itself.
The sternal reversal proposed by Judet in 1954 was a new concept of treatment, and in 1968, Wada in Japan performed a reported surgery with numerous cases. He cut off the entire deformed sternum, flipped it and sutured it to a normal position. This surgical approach was not widely used outside of Japan because of the many complications in the event of infection.
In 1990, Pena and co-workers mentioned the problem of thoracic growth and development after removal of the entire rib cartilage, and they reported that the thorax no longer grew and developed after removal of the rib cartilage in young rabbits. in 1996, Haller and co-workers described a similar phenomenon occurring in humans, where thoracic growth restriction occurred after overly extensive and premature funnel chest surgery. Following the publication of these two papers by Pena and Haller et al, attention was drawn to the risk of developing “acquired asphyxial chondrodystrophy”. Since then, most surgeons have stopped performing open-heart surgery in pediatric funnel chests and have waited until after puberty. Cartilage resection has also been reduced, and is known as a “modified Ravitch procedure”. Pediatricians are less likely to refer children for corrective surgery.
DonaldNuss
In 1986, while operating on a patient with a funnel chest, Donald Nuss was struck by the good elasticity of the rib cartilage and wondered, “If these ribs are so elastic and malleable, why do I have to remove them?” The question should further be, “If not, what else can we do?”
In the next funnel chest surgery, Nuss made a standard skin incision in the chest wall, choosing not to remove the thoracic skin and muscle (which had to be removed to reach the rib cartilage and sternum), nor did he want to remove the rib cartilage and sternum. So, a small opening is made between the ribs at the level of the lowest point of the sternal recess, and then a long curved forceps is stabbed into the chest wall, subtly creating a tunnel behind the sternum, and the curved forceps are threaded through the chest wall on the other side. A band is tied to the end of the curved forceps, and then the curved forceps are withdrawn from the posterior sternal tunnel, where the band is used to guide the bent titanium plate convexly backward through the posterior sternal tunnel. Once the plate is passed through in the proper position, the plate is flipped 180 O. This completely corrects the funnel chest without rib and sternal margin resection and with essentially no bleeding.
Unfortunately, the previous titanium plate was too soft for this new surgical approach, and after 6 months the good results began to deteriorate, so the titanium plate was the first device to be modified. The second modification was to change the anterior chest wall incision from one to two on one side. The new improved device made the procedure easier and safer. Most importantly, the use of the thoracoscope allowed the surgeon to see inside the thorax, greatly reducing the risk of surgery.
This surgical approach was quickly accepted by surgeons worldwide, and in 1997, Nuss et al. published a 10-year experience with the Nuss procedure. This minimally invasive procedure does not require the removal of rib cartilage and sternal truncation, which relies on the internal support of the elastic and malleable rib cartilage. The surgical rationale is based on 3 points.
1. The pediatric chest wall is more pliable
In the pediatric population, the chest wall is softer and even very minor airway obstruction may lead to severe sternal collapse. Trauma rarely leads to rib fractures, hypophyseal thorax, etc. The American Heart Association recommends using only two fingers for cardiac compressions in smaller children and only one hand for cardiac resuscitation in older children to avoid cardiac rupture.
2, middle-aged and elderly chronic obstructive pulmonary disease (such as emphysema)
Patients can be reactive to shape the barrel chest. If the chest wall can be remodeled in middle-aged and elderly people, children and adolescents with a more flexible anterior chest wall should also be able to undergo chest wall remodeling.
3. Braces and metal devices are used by orthopedic
Orthodontists are used to correct bony deformities such as scoliosis, deformed feet and upper and lower jaw malocclusion with success, and the role of these devices has been affirmed. The anterior chest wall is clearly more extensible than the above-mentioned bony deformities, so the chest wall can also be corrected in this way.
Eckart-Klobe negative pressure cup
The first use of negative pressure techniques to elevate the sternum was over 100 years ago. This method has been mentioned in medical textbooks and is still occasionally referenced. However, it seems that only Lange has experience with the practical application of this method.
Although the use of this negative pressure technique in therapy has made almost no progress, the use of materials has advanced significantly. Just as in many industrial applications, negative pressure devices can produce powerful forces. Negative pressure cups can also be used in the Nuss procedure, where the most dangerous step in the procedure is the passage of the penetrator between the heart and the sternum. With the use of a negative pressure cup, the sternum can be lifted within minutes, reducing the risk of damage to the heart. In addition, the use of a negative pressure suction cup for several months prior to surgery may improve the final surgical outcome.
Negative pressure is generated by a patient-held pump device, and air is expelled from the suction cup until the internal pressure drops to less than 15% of atmospheric pressure. The treatment procedure is documented by photographs, radiographs and depression markers. Negative pressure suction cups are available in 3 sizes (16cm, 19cm and 26cm diameter) and are selected according to the patient’s age.
In a preliminary study conducted by Bahr and Schier in Jena, Germany, this negative pressure device immediately raised the sternum and ribs. In addition, this was also confirmed thoracoscopically in minimally invasive surgery for funnel chest (MIRPE). According to the manufacturing instructions and our experience, the negative pressure cup should be used at least twice a day for 30 minutes each time and up to several hours a day.
Complications and associated side effects include subcutaneous hematomas, subcutaneous petechiae, back pain and transient upper extremity sensory abnormalities that occur with use, and rib fractures occur rarely. Contraindications to this method include bony disorders (e.g., osteogenesis imperfecta and Glisson’s disease), vascular disorders (e.g., Marfan’s syndrome and abdominal aneurysms), coagulopathies, and cardiac disease. To exclude these diseases, an examination and evaluation should be routinely performed before starting treatment.