Children with congenital chest wall anomalies present from infancy to adolescence with cosmetic, psychological, or physiologic concerns. The spectrum of major anomalies of the chest wall includes pectus excavatum, pectus carinatum, Poland’s syndrome, sternal clefts, and Jeune’s syndrome.^1,2 The most common anomaly, pectus excavatum, is a concave depression of the sternum that comprises of majority of referrals seen by a pediatric surgeon for chest wall defects. Genetic or chromosomal associations with chest wall deformities are rare and include connective tissue disorders such as Marfan’s and Ehlers–Danlos syndromes.^3,4 This chapter reviews the embryology of chest wall development as well as the pathophysiology, diagnosis, and treatment of the various congenital chest wall anomalies.

The first reported repair of the pectus excavatum deformity, by Meyer, occurred in 1911.⁵ Several reviews followed, but the benchmark repair, including costal cartilage excision and sternal osteotomy, was described by Ravitch in 1949 and has undergone only minor modifications in over 50 years of use.⁶ Recently, experience has been growing with a minimally invasive technique for pectus excavatum repair described in 1998 by Donald Nuss.⁷ Ravitch is also credited with the first repair of a pectus carinatum defect in 1952.⁸ Jeune and colleagues described the syndrome of asphyxiating thoracic dystrophy in 1954,⁹ and Cantrell, in 1958, described the pentalogy that includes lower sternal clefts.¹⁰

The chest wall consists of muscles derived from myotomes and ribs, costal cartilages, and components of the sternum from the axial skeleton. Shortly after the fifth week of development, dermomyotomes in the thoracic region split and form myotomes, from which the chest wall musculature arises. The mesenchymal costal processes of the developing thoracic vertebrae give rise to the ribs starting at week 5 after fertilization.^11,12 During the embryonic period, the costal processes become cartilaginous and finally undergo endochondral ossification to become ribs. The synovial costovertebral joints arise from the embryonic junction between the vertebrae and the costal processes. During week 6 of development, a pair of vertical mesenchymal structures, known as sternal bars, develops ventrolaterally along the body wall. These bars gradually fuse craniocaudally in the median plane as they chondrify to form precursors of the manubrium, sternebral segments of the sternal body, and xiphoid process. Ossification of the sternum also occurs in a craniocaudal fashion and is complete by 60 days postfertilization except for the xiphoid, which ossifies after birth. Incomplete sternal fusion is not uncommon and can lead to bifid xiphoid or a spectrum of sternal clefts.

Abnormal growth, lengthening, rotation, or increased elasticity of the costal cartilages leads to the relatively common depression of the sternum known as pectus excavatum. Clinical findings usually begin to manifest by 2 to 3 years of age, but—given the risk of acquired thoracic dystrophy or recurrence after correction in younger patients—operative intervention should occur in older children or adolescents. The physiologic benefit of pectus excavatum repair is frequently discussed but remains controversial and is based mostly on retrospective data. Two repairs are most commonly performed, an open repair, first described by Ravitch, and a less invasive bar repair, described by Nuss. The type of repair is chosen based on the surgeon’s experience and the complexity of the deformity. Both techniques have demonstrated good results when the appropriate patient is selected at the appropriate age for repair. The latter approach described by Nuss has become more popular in many centers across the world. These patients are not only referred for the Nuss procedure by primary care physicians, but majority of such patients are self-referred because of information available on the World Wide Web.¹³

There is no known cause for pectus excavatum. Cartilaginous growth appears to be abnormal, which causes either posterior depression of the sternum in the case of abnormal lengthening of the cartilages or rotation of the sternum in the case of differential cartilaginous growth. The sternum itself does not appear to play a causative role in excavatum or carinatum. A study of the biomechanical, morphologic, and histochemical properties of cartilage from children with pectus excavatum shows decreased tension, compression, and flexure, with disrupted type II collage patterns in the deep zones of the cartilage.¹⁴

Pectus excavatum is relatively common, occurring in approximately 1:400 live births, with a male predominance of up to 5:1.¹⁵ No genetic abnormalities or chromosomal aberrations have been associated with pectus excavatum, although a familial tendency has been described.^15,16 Up to two-thirds of children with Marfan’s syndrome and a high frequency of Ehlers–Danlos patients develop pectus excavatum deformities.^3,4 Children with connective tissue disorders can present later in life, have more progressive defects, and suffer from more complicated postoperative courses, but successful cosmetic and functional results can be achieved even in these patients.⁴ Other associations include cardiac disorders¹⁷ and scoliosis.¹⁸

Pediatric surgeons performing pectus excavatum repair argue that children with pectus excavatum seem to enjoy an increase in stamina and cardiovascular performance after surgical correction. However, it is unclear whether the cardiopulmonary advantages are conferred on these patients after undergoing repair of their pectus excavatum. These advantages quoted in the literature are mostly based on retrospective data.^19,20

Two organ systems have been examined for physiologic differences in pectus excavatum: pulmonary and cardiovascular. Static pulmonary function tests performed at rest seem to show few abnormalities in children with pectus.^21,22 Other studies have confirmed the lack of difference in static lung volumes and baseline resting pulmonary function before and after both Ravitch and Nuss repairs,^23,24 while some even argue for a possible worsening of lung function after chest wall reconstruction.^25–28 In reviewing these studies, the majority of children are at the lower end of the “normal range” of pulmonary function, suggesting a defect. Interestingly, decreased postoperative pulmonary function testing in some studies has been found in contrast to subjective improvement in exercise stamina.²⁷ In some studies, including those that show no difference in resting pulmonary tests, exercise pulmonary function shows significant differences in lung volumes in preteen and teenaged pectus patients.^21,29 A recent study by Haller and coworkers shows a lower forced vital capacity (FVC) in pectus patients before surgery, with over half complaining of exercise limitation; significant improvement was found in 66 percent of these patients after repair.³⁰ Patients with abnormal ventilation/perfusion scintigraphy scans have demonstrated improvement after surgical correction of pectus deformity.³¹ Although vital capacities were reported as only mildly reduced or normal in pectus patients, a nonlinear increase in oxygen uptake was seen when compared with controls, possibly indicating an abnormal work of breathing during exercise.³² In another study, all pectus patients experienced improvement in maximal voluntary ventilation and exercise tolerance.³³ Some authors believe that the improvement of pulmonary function after pectus repair can be appreciated only in children who have severe deficits preoperatively.³⁴

Reduced cardiovascular performance, rather than ventilatory limitations, has been the focus of a number of studies in an effort to understand the physiologic manifestations of pectus excavatum.^35,36 Right ventricular filling seems to be diminished with this condition and somewhat alleviated after repair.³⁷ Kowalewski and colleagues showed increased right ventricular systolic, diastolic, and stroke volumes after surgical correction of pectus excavatum.³⁸ A lower heart rate and expanded cardiac stroke volume have been described after pectus repair,^27,28,33 as has a higher oxygen pulse and cardiac output.^29,30 For this reason, routine cardiology evaluation in patients with known rhythm abnormalities, right atrial and ventricular hypertension, and mitral valve prolapse is prudent. Studies have indicated a significantly higher proportion of patients with mitral valve prolapse in patients with pectus excavatum when compared with control children in the same age group.¹³

In addition to the apparent cardiopulmonary advantages of pectus repair, the psychological and psychosomatic aspects associated with this disease cannot be underestimated. School-aged children with pectus excavatum suffer from embarrassment, social anxiety, orientation toward failure, marked depressive reactions, feelings of stigmata, reduced tolerance of frustration, and limited capacity for work.³⁹ In many children, these body image issues alone merit surgical intervention; when combined with the apparent cardiopulmonary advantages of correction, these considerations should clearly urge all health care providers to be supporters and advocates of treatment of pectus excavatum.

Figure 19-1 illustrates the classic physical features of a child with pectus excavatum. Most children who present for surgical evaluation are active and healthy-appearing, with the chief complaint of a visible anatomic defect. Several relatively younger patients may also present to the office with their parents who clearly recognize the anatomic defect but is not obvious to the child. Physical examination of such children may demonstrate sloped ribs, rounded shoulders with a classic stooped posture, and a protuberant abdomen. When the excavatum defect is severe, the cardiac point of maximal impact can be shifted laterally beyond the midclavicular line. Pectus excavatum is most commonly discovered in the first few years of life, although it can be apparent in the newborn period or in a delayed fashion later in development. In newborns, pectus excavatum can be associated with paradoxical chest wall movement with ventilation. Although pectus excavatum may present at birth, most patients present after prepubertal spurt. These are typically boys in majority of the case. 20 to 30 percent of such patients may have accompanying scoliosis. Marfarnoid features may be seen in up to 20 percent of such patients.¹³ Many of these anomalies can resolve spontaneously during the early years and should not be considered for surgical repair until ages 8 to 12.

Physically active children often complain of shortness of breath during exercise or decreased exercise tolerance when compared with their peers, but they generally have no symptoms at rest. Excessive tachycardia or palpitations during mild exercise can also be seen in patients with this disorder.¹⁵ In a 30-year review of 375 patients undergoing pectus repair, 67 percent reported preoperative decreased stamina and endurance during exercise, 32 percent had frequent respiratory infections, 8 percent had chest pain, and 7 percent had asthma.⁴⁰ Another 30-year study found, at initial presentation, 56 percent of subjects with dyspnea on exertion, 29 percent with shortness of breath at rest, 10 percent with chest pain, and 10 percent with palpitations.⁴¹ Table 19-1 summarizes the signs and symptoms of pectus excavatum.

Many centers will begin the workup with a preoperative chest radiograph. Apart from being readily available and inexpensive, it allows measurement of severity index. In children with recurrent pectus excavatum, it helps detect the extent of abnormal calcification of cartilages. Regardless of the surgical approach selected, the best radiographic test for preoperative evaluation of a patient with pectus excavatum is computed tomography (CT) of the chest.^42–44 This study provides precise information regarding cardiac displacement, lung volume, and, most importantly, the most accurate measurement of the depth of the sternal defect and its relationship to the overall width of the thorax.⁴⁵ The Haller index can be obtained by measuring the ratio of the AP distance between the vertebral bodies and the sternum at its narrowest point and the transverse diameter of the chest. This can be performed on physical exam or more reliably by a CT scan. Although age and gender-related variability exists in the Haller index,⁴⁶ normal children should not have a Haller index greater than 2.5, while the severity index of those with pectus excavatum generally ranges from 3 to 6 (Figs. 19-2 and 19-3A and B). Magnetic resonance imaging (MRI) has been used in patients where radiation exposure is a concern, particularly in those children that are cooperative and do not need sedation or general anesthesia for MRI.

Factors determining candidates for repair of pectus excavatum defects include anatomic, physiologic, psychological, considerations as well as proper timing (Table 19-2). A CT scan can accurately define the anatomic defect, including the severity index of the sternal depression as well as its effects on cardiac and pulmonary anatomy. A Haller index of 3 or greater is associated with the presence of pectus excavatum.

All candidates should undergo stress pulmonary function studies and, if indicated by stress pulmonary function or history, echocardiography. Based on patient and family history—including double joints, joint dislocations, hyperflexibility, accelerated worsening of eyesight, and mitral valve prolapse—a screen should be considered for connective tissue disease. Associated chest pain, dyspnea on exertion, decreased exercise tolerance, exercise-induced asthma, or cardiac anomalies are possible indications for operative correction.^{27,28,33–36} Patients who begin with symptoms such as dyspnea on exertion or exercise-induced chest pain show significant improvement of these symptoms postoperatively.^40,47 In addition, the need for future sternotomy, as in children with Marfan’s syndrome, should be considered an indication for correction in childhood.⁴⁸

Psychological symptoms are not uncommon in these patients and include embarrassment reactions, marked depressive reactions, social anxiety, feelings of stigmata, and others.³⁹ These manifestations can seriously alter the mental and physical health of a child and should be strongly considered in deciding candidacy for operative repair.

Proper timing of surgical repair is essential for adequate outcome, although this is also frequently debated and based on retrospective data. In general, good results have been reported with correction in school-aged children between the ages of 8 and 16, either before or after but not during their pubertal growth spurts.^15,42,49 The advantage of undergoing a repair before puberty is the ability of the bar to stabilize the malleable chest during this period and throughout the puberty spurt. This in turn leads to shorted recovery time and low incidence of recurrence.⁴⁸ It remains clear that Ravitch repair in patients younger than 7 years of age should be avoided because of a higher incidence of damage to the cartilaginous growth centers, with resulting acquired Jeune’s syndrome.^30,50–53 A Nuss repair in patients around 8 years of age is sometimes justified when they have significant cardiopulmonary compression from their defect. In such situations, the bar should be left for up to 3 years. Additionally, the parents should appreciate that there is a higher risk of recurrent pectus excavatum when repaired at this age. The reason for higher recurrence in this age group is the removal of bar prior to pubertal growth spurt. Timing should vary with indication, as with the example of lower incidence of recurrence in children with Marfan’s syndrome who underwent repair after maximal growth was obtained.⁵⁴ Success has been reported with simultaneous correction of pectus excavatum and congenital cardiac defects.⁵⁵ Age should not be a barrier to repair, as excellent long-term cosmetic results and symptomatic relief approaching 90 percent have been described in adults between the ages of 16 and 68 years.⁴¹

Almost 60 years ago and for several decades to follow, Ravitch described subperichondrial resection of the lower costal cartilages with wedge osteotomy of the sternum as a possible repair for pectus excavatum.^6,56,57–60 This has gained wide acceptance as the gold standard operation for pectus excavatum, especially for complex or recurrent cases. Extensive experience has been reported with this procedure, and outcomes are generally excellent.^{42,44,61–66} One group has reported some success with a minimally invasive endoscopic Ravitch repair.⁶⁷

Incision and Exposure

A modified Ravitch repair as performed at Johns Hopkins Hospital has been described (Table 19-3). A transverse inframammary skin incision is utilized at the level of the deepest portion of the sternal defect. Usually cosmetic outcomes from transverse incisions for this operation are more appealing than vertical ones. Upper and lower skin flaps are created in the subcutaneous layer, followed by creation of midline muscle flaps elevating the pectoralis muscles. This exposes the costal cartilages in their entire length bilaterally along the affected portion of the sternum. In most cases, this includes the fourth through seventh cartilages, but it can include as high as the second and third in severe cases of pectus excavatum. Exposure of the upper flap should extend to at least one normal cartilage cranial to the uppermost abnormal one, with the goal of excising at least four cartilages bilaterally.

Subperichondrial Resection

One of the two principal goals of the operation is subperichondrial resection of all abnormal costal cartilages (Fig. 19-4A). These are resected from the lateral point of union with the rib, extending medially to the chrondrosternal junction. To keep the resection subperichondrial, the perichondrium is incised anteriorly along each cartilage, and upper and lower flaps of perichondrium are created to expose the deformed cartilage. It is imperative to keep the perichondrium entirely intact and not devascularized, as this provides the basis for new cartilage growth and subsequent bone. It is also suspected that devascularization of the perichondrium can contribute to the acquired Jeune’s syndrome. During the dissection of the posterior perichondrium, care must be taken to avoid violating the pleural space.

Wedge Osteotomy

The xiphoid is exposed and elevated, allowing for the creation of a substernal plane (Fig. 19-4B). This is performed mostly by blunt dissection, taking meticulous care to preserve the pleura and the pericardium as it is swept from the posterior surface of the sternum. The perichondrial bundles at the level of all of the excised cartilages are detached from the sternum, making sure that the internal mammary artery is swept laterally with the intercostals bundle and perichondrium. Just above the resected cartilages, the wedge osteotomy is performed (Fig. 19-4C). This is an anterior, triangular incision in the anterior table of the sternum performed to correct the posterior depression of the sternum by bringing it to a more anterior and neutral position. A single osteotomy is usually performed between the second and third cartilages, although at times a second osteotomy can be performed in a more caudal location (Fig. 19-4D). Tripod supports consisting of the lowest third or fourth intact costal cartilages can be used to support the sternum as well by obliquely dividing them in a medial-to-lateral trajectory and then placing the medial portion atop the lateral. Finally, for further security, the sternal periosteum is sutured in the position fashioned during the operation (Fig. 19-4E).

Support Bar

Various modalities have been described to further support the sternum after wedge osteotomy. Autologous perichondrium has been used,⁶⁸ as have various metal struts with or without synthetic envelopes.⁶⁹ We prefer selective use of stabilizing struts for patients over the age of 10 or 12 or those with connective tissue diseases such as Marfan’s or Ehlers–Danlos syndrome. A substernal stainless steel bar can be placed under the distal third of the sternum and secured in place laterally to the medial aspect of surrounding ribs (Figs. 19-4F and 5A and B). Interrupted sutures are generally sufficient to secure the bar. Alternatively, sternal fixation bars, which need to be sized and bent to configure to the contour of the sternum, can be screwed in place (Fig. 19-6A and B).

Postoperative Management

It is not necessary to suture intercostal bundles that have been detached from the sternum back into place. If this defect is small, however, it can be closed by approximating nearby tissues. Retrosternal and subcutaneous chest drains are placed and can be removed 2 to 3 days postoperatively. After drains are removed, oral analgesia is sufficient and patients can be discharged within 3 to 4 postoperative days. A bladder catheter is recommended for the first day or two in the teenager and older patient, in whom urinary retention is not uncommon. Incentive spirometry is critical to prevent atelectasis. Contact sports for 6 to 8 weeks are usually avoided to allow cartilage regrowth and sternal fixation. A support bar, if placed, should remain for at least 6 months and can be removed in an outpatient procedure.

Outcomes and Complications

For almost six decades, thousands of patients with pectus excavatum have been successfully treated with some modification of the Ravitch repair and followed for significantly long periods of time.^{15,24,40–42,44,47,63,65,70–77} This is the gold standard operation to which all new techniques are compared.

The psychological benefits of the operation are clear.³⁹ The physiologic benefits of pectus repair remain controversial, with some groups demonstrating a measurable physiologic advantage^{21,27–33,37} and others showing no difference before and after corrective operations.^23–28 It is possible that only selected patients with certain preoperative physiologic handicaps will benefit in this regard from surgical repair.

Hospitalization rarely exceeds 3 days, and 97 percent of patients experience a good result from the operation.¹⁵ Although the operation is mostly performed in male patients, females with pectus deformities fare equally well after surgical repair.⁷⁰ Complications generally occur in fewer than 5 percent of patients undergoing a modified Ravitch repair; these are listed in Table 19-4. Early complications include pneumothorax, pleural effusion, pericarditis, seroma, wound infection, urinary retention, and atelectasis. Bar migration and pectus recurrence can occur as late complications. Acquired Jeune’s syndrome is a terrible complication and is discussed later in this chapter. Urinary retention is usually seen in older teenagers and adults and 1 to 2 days of bladder catheterization is required in this population. In addition, aggressive pulmonary toiled is advocated to reduce atelectasis and the risk of pneumonia. Recurrence occurs in approximately 2 percent of patients, with a higher incidence if the operation was performed at an early age (below 7 years).

In a review of 375 patients over 30 years, Fonkalsrud and associates report 12 cases of atelectasis, 13 pleural effusions, 5 recurrences, and 3 patients with pericarditis.⁴⁰ Of 777 procedures for pectus repair in a single center, 98.5 percent were successful, with an overall complication rate of 6.7 percent, a major recurrence rate of 1.5 percent, and a minor recurrence rate of 4.5 percent.⁷³ Shamberger and coworkers reported 704 patients seen over a period of 30 years who were repaired by a modified Ravitch technique, with 4.4 percent rate of complications including 11 cases of pneumothorax, 5 wound infections, 1 seroma, 1 hemopericardium, and 17 major recurrences (2.7 percent), of which 12 required revision.⁴⁴