History
Some patients with pectus excavatum experience chest and back pain that is usually musculoskeletal in origin. The exact cause of the pain is poorly understood. Pectus excavatum and pectus carinatum are frequently associated with scoliosis. Although such association is probably coincidental, the poor posture noted in many patients with pectus deformities may be a key factor in the development of pain.
Pulmonary function
Many physicians attribute the symptomatic impairment in pectus excavatum to a decrease in intrathoracic volume secondary to the sunken chest. However, this relationship is difficult to prove because of the wide range of pulmonary function among healthy individuals and the correlation of pulmonary function with physical training and body habitus. The reported pulmonary function abnormalities have ranged from being normal in young patients to restrictive or obstructive defect in older patients with marked defect. Elevated residual volume has been reported. [3] There has been scientific evidence reported that demonstrates shortness of breath upon exertion in patients with pectus excavatum, primarily due to the decrease in pulmonary reserve. [4]
Clinicians have observed that many patients with pectus excavatum tend to become symptomatic during their teenage years or early in adult life. Patients younger than 10 years who have pectus excavatum do not typically experience symptoms associated with shortness of breath.
A prospective study of preoperative and postoperative pulmonary function following corrective surgery for pectus excavatum found that there is significant improvement in lung function at rest and in VO2 max and O2 pulse after surgical correction of pectus excavatum, with CT index >3.2. According to the study, operative correction significantly reduces CT index and markedly improves the shape of the entire chest and can be performed safely in a variety of centers. [5] ] ,[ [6] In 1984, Cahill et al reported that, after operative repair, lung capacity improved little, and maximal voluntary ventilation significantly improved in patients with pectus excavatum who had low-to-normal vital capacities prior to surgery. [7] Exercise tolerance was also improved, as measured by total exercise time and maximal oxygen uptake. The heart rate at a given level of work or exercise consistently decreased postoperatively, but oxygen consumption to support an improved efficiency of work was not changed.The observed decrease in heart rate at each workload capacity was a result of increased cardiac stroke volume.
In 1967, Weg et al evaluated 25 US Air Force recruits with pectus excavatum and compared them with healthy trainees. [8] Although the lung compartments and mean vital capacities of both groups were equal, the maximum voluntary ventilation significantly deviated from predicted reference range values (P = 0.005).
In 1996, Quigley et al studied 36 adolescents (mean age 16 y) with pectus excavatum. [9] Quigley et al reported a significantly lower forced vital capacity in the study group than in an age-matched control group. Moreover, an inverse relationship was observed between the vital capacity and the degree of sternal compression, suggesting that such patients would benefit from operative correction of the pectus deformity.
Cardiac function
Posterior displacement of the sternum in pectus excavatum can produce a heart deformity, with anterior indentation of the right ventricle. Early pathologic studies demonstrated this finding, and a series of early case reports included cardiac evaluations for patients with severe symptoms. Angiographic studies have demonstrated the sternal imprint on the anterior wall of the right ventricle.
Several studies have demonstrated limitation of cardiac stroke volume in patients with pectus excavatum, particularly in the sitting, or upright, position. When patients with pectus remain in the supine position (lying flat), no significant impairment to cardiac function is apparent. Further evidence has suggested that operative repair of pectus results in normalization of the cardiac function.
A study by Zens et al found that ventricular systolic dysfunction is related to the severity of pectus excavatum. In addition, cardiopulmonary exercise testing showed that 33% of patients in the study had reduced aerobic fitness. [10]
One study assessed cardiac workload in 13 patients with pectus excavatum. [11] The patients were assessed in an upright position on a bicycle ergometer. Findings suggested that, following surgery, most patients could more easily reach the target heart rate during exercise without becoming symptomatic. Many use this observation as substantial evidence that operative repair for pectus excavatum results in improved cardiac function. However, the role of conditioning and subjective response to surgery is difficult to assess.
Physical Examination
The hallmark of pectus excavatum is the caved-in appearance of the anterior chest. As mentioned above, the severity of the defect and the asymmetry of the chest widely vary. Patients may present with a very mild form of pectus excavatum or their sternum may be almost touching the spine. Typically, the lower third of the sternum is more involved, and the upper third may appear fairly normal. A compensatory anterior flaring of the lower ribs at each costal margin is also common. Many patients have associated scoliosis, but this is not directly related to the presence of pectus excavatum.
Heart sounds are typically displaced to the left side because of displacement and rotation of the heart. A click sound of mitral valve prolapse may be present. Lung sounds are clear, but the lung sounds may appear diminished at both bases because of decreased pulmonary volumes.
The term pectus posture refers to the position assumed by most patients with significant pectus excavatum. They appear to create an anterior curvature of the thoracic spine with the shoulders slumped forward. Whether this is a subconscious maneuver to hide the chest wall deformity or a postural defect directly related to pectus excavatum is unclear. Such positioning of the spine appears to accentuate the pectus excavatum and can generate spine problems related to poor posture and inadequate spinal support. Correcting this posture is quite difficult, even after successful repair of the pectus excavatum.
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A 16-year-old boy with severe pectus excavatum. Note the appearance of the caved-in sternum and lower ribs.
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A 10-year-old girl with severe pectus excavatum. In girls, the deformity is of particular concern because of the medial displacement of the breast, resulting in significant asymmetry of the breasts and nipples (cross-eyed appearance of the nipples).
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A 10-year-old girl with severe pectus excavatum. Note the significant asymmetry of the breasts and nipples (cross-eyed appearance of the nipples).
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A 12-year-old girl with severe pectus excavatum. Note the significant asymmetry of the breasts. Preoperative photograph.
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A 12-year-old girl with severe pectus excavatum immediately after minimally invasive repair. Note the immediate correction of the deformity.
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Preoperative photograph of a 12-year-old boy prior to minimally invasive repair of pectus excavatum.
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A 12-year-old boy 2 weeks after minimally invasive repair of his pectus excavatum. Note the small lateral chest wall incision and the excellent appearance of the anterior chest with 100% correction of the pectus deformity.
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Preoperative CT scan of the chest of 12-year-old girl with severe pectus excavatum (see Media file 5). Note the severe pectus excavatum with compression of the lung fields and complete displacement of the heart and mediastinal structures to the left hemi-thorax.
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Illustration showing the minimally invasive technique for correction of pectus excavatum (3) with thoracoscopy (1). Note the long clamp passed from one side to the other (2) grabbing the umbilical tape (4), which serves as a guide for passage of the pectus bar behind the sternum.
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Operative diagram illustrating the pectus bar after it has been passed behind the sternum (5), under thoracoscopic visualization (1), before turning it over. Note that the concavity of the bar is facing up.
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Illustration of the pectus bar passed behind the sternum before and after it is turned over. The insert shows the proper technique for fixation of the pectus bar against the lateral chest wall musculature.
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Illustration of the placement of the third point of fixation for stabilization of the pectus bar. Note that the nonabsorbable suture is placed around the bar and around a rib, lateral to the sternum on the anterior chest wall.
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Operative diagram illustrating one of the open techniques for correction of pectus excavatum. The drawing is of the so-called "turn-over operation" for repair of pectus. It shows the extensive dissection and the radical nature of this open technique for surgical correction of this congenital chest wall deformity.
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Operative photograph of the open Ravitch technique for repair of pectus excavatum. The anterior chest is exposed through an anterior thoracic incision and, after raising muscle and skin flaps, each involved cartilage is excised with preservation of the perichondrium. The picture shows one of the cartilages being removed.
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Operative photograph of the completed Ravitch procedure for correction of pectus excavatum. Note the sternum fractured at 2 different points with a cartilage graft in place to maintain its new position. The involved ribs underwent perichondrial excision. The deformity is completely corrected.
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Closure of the anterior chest wall incision used for the open type of repair of pectus excavatum (Ravitch operation). Note the drain (small tubing) coming out on the side of the chest. Drains are typically removed after 2-3 days, and they prevent the accumulation of fluid under the skin and muscle flaps created at the time of surgery.
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Chest radiograph of a 16-year-old patient in which the bar was displaced superiorly and the 2 stabilizers were separated from the Lorenz pectus bar as a result of intense physical activity during soccer practice.
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Skin rash secondary to a rare case of metal allergy caused by the pectus bar.
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Recurrent pectus excavatum in a 24-year-old adult patient who underwent open repair using the Ravitch technique at age 10 years.
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Chest CT scan of the recurrent pectus excavatum in the patient in Media file 20.
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Recurrent pectus excavatum in young adult female patient who underwent minimally invasive repair at age 8 years.
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Technique for pectus bar bending. The Lorenz bar is bent by the operating surgeon at the time of pectus bar placement using an instrument known as the "bar bender." A smooth curvature is given to the bar so that it fits under the sternum and corrects the pectus deformity.
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Pectus bars of various sizes.
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Technique for removal of the pectus bar. The bar and lateral stabilizer are easily exposed through the old lateral incision in the chest. Once exposed, it is pulled out using a bone-hook instrument.
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Technique for removal of the pectus bar. The bar is pulled out using a bone-hook instrument.