Numerous methods of surgical repair have been proposed and used. The continued use of multiple techniques bespeaks the failure to achieve uniformly superior results by any one method. All techniques have some risk of recurrence. Selection of an approach must be based not only on the ultimate results and long-term recurrence rates, but also on the potential complications intrinsic to the procedure. A technique that achieves safe, satisfactory correction of pectus excavatum with total preservation of the perichondrial sheaths of the costal cartilage, preservation of the intercostal muscle bundles, and anterior fixation of the sternum was reported by Baronofsky in 1957 and by Welch in 1958. This technique has been used in more than 700 cases at Children's Hospital Boston over the past 3 decades.
In 1997, Nuss described minimally invasive pectus excavatum repair by placing a convex steel bar beneath the sternum and anterior to the heart through lateral thoracic incisions to elevate the sternum. Since this initial report, the Nuss procedure has been performed in more than 1400 patients at Children's Hospital of The King's Daughters alone. Numerous modifications have optimized the safety and effectiveness of the technique. These improvements include (1) routine use of thoracoscopy with CO2 insufflation for better visualization and safety and (2) pectus bar stabilization and fixation using both an attached metal stabilizer on the lateral bar and pericostal suturing around the bar and the underlying ribs medially to minimize postoperative bar displacement.
Two other types of repair should be mentioned. Haller and associates use a 3-point “tripod” fixation by placing an osteotomy and creating oblique chondrotomies of the upper costal cartilages angled from anteromedial to posterolateral. The medial portion of the costal cartilage attached to the sternum can then be laid on the lateral portion of the cartilage attached to the rib to help support the sternum anteriorly.
A “sternal turnover” technique was proposed by Judet and by Jung in the French literature. This technique has been employed primarily by Wada, who reported a large series from Japan. The “sternal turnover” technique essentially uses a “free graft” of the sternum that is rotated 180° and secured to the costal cartilages. This technique is a radical approach for children with pectus excavatum, considering the major complications reported when infection occurs and the generally successful alternatives available.
The majority of repairs now rely on the Nuss technique. Open repair is used primarily for patients with severe asymmetry of the chest wall (particularly when it involves the lower “floating” ribs), mixed pectus deformities (elements of both excavatum and carinatum), or for individuals who do not wish to have the bar in place for 2 to 3 years. These approaches are described in depth in this chapter.
Minimally invasive pectus repair is indicated for patients with a severe pectus excavatum deformity and associated physiologic impairment. Specific inclusion criteria include 2 or more of the following:
CT index greater than 3.25 with associated cardiac or pulmonary compression;
pulmonary function studies demonstrating restrictive and/or obstructive impairment;
cardiology evaluation demonstrating cardiac compression, displacement, mitral valve prolapse, murmurs, or conduction abnormalities; and
documentation of progression of the deformity with advancing age in association with development of or worsening of physiologic symptoms (ie, shortness of breath, lack of endurance, exercise intolerance, palpitations, and chest pain).
The optimal timing for minimally invasive repair appears to be 10 to 14 years of age while the chest wall is still malleable. Surgery in these children is associated with a shorter recovery and ensures that support from the pectus bar is provided during the adolescent growth spurt. Repair at a younger age is certainly appropriate in the setting of severe cardiac or pulmonary compression with associated clinical signs of physiologic impairment. Bars placed in children at younger ages are typically left in situ for longer periods of time as these children grow. Repair in postpubertal patients in characterized by a higher likelihood of requiring placement of multiple bars due to increased chest wall stiffness, but is generally well tolerated.
Prior to surgery, the patient's anterior chest wall circumference (from right to left midaxillary lines) at the level of the deepest sternal depression should be measured to approximate appropriate pectus bar length. The length selected is typically 1 to 1.5 inches shorter than this outer circumference. Any patient with a history of eczema or atopy should be skin tested for metal allergy. Those patients with positive skin tests or history of nickel allergy should have titanium bars placed. These titanium bars must be specially ordered and will arrive prebent from the manufacturer (Biomet Microfixation, Jacksonville, FL) based on measurements from the patient's chest wall and chest CT scan.
The patient is placed in the supine position with both arms abducted to expose the lateral chest wall on each side. A single dose of cefazolin is administered. After prepping, important landmarks to identify on the anterior chest wall include the deepest point of the sternal deformity and the lateral ridge of the deformity on each side. The goal is to place the pectus bar in a horizontal plane encompassing the intercostal spaces at the pectus ridge on each side and the deepest point of sternal depression. Bilateral thoracic incisions are planned at this level. If multiple bar placement is planned, it may be necessary to make separate thoracic incisions for each bar placed. In female patients, inframammary incisions are performed because they provide good access to the anterior chest wall and enhanced cosmesis.
Creation of the Transthoracic Tunnel
The first step of the repair process entails creation of a tunnel extending through the subcutaneous/submuscular tissues on one side of the chest, beneath the medial ribs and sternum in the intrathoracic and mediastinal spaces, and out through the subcutaneous/submuscular tissues on the opposite side of the chest (Fig. 17-3). A thoracoscopic port is placed approximately 2 interspaces below the planned right thoracic incision, and pneumothorax is achieved with low-pressure CO2 insufflation. A 30° thoracoscope is inserted to confirm the internal anatomy in preparation for substernal dissection. Lateral transverse thoracic incisions are made on each side of the chest wall from mid- to anterior-axillary lines and advanced medially to the pectus ridge in a subcutaneous plane using blunt and sharp dissection. If there is pectoralis muscle present at the level of this dissection, the tunnel should be made beneath it. In patients with sternal depression predominantly involving the upper chest, care should be taken not to create the tunnel too high on the chest wall because bar placement at this site could interfere with the nerves and vessels of the axilla and/or cause chronic pain.
Nuss procedure, creation of the transthoracic tunnel. A. Bilateral subcutaneous tunnels are created to pectus ridge (X) on each side in the horizontal plane of deepest sternal depression (•). With thoracoscopic visualization, a tonsil clamp is inserted through intercostal space medial to pectus ridge and into right pleural space. B. The pectus introducer is advanced through the tunnel and right intercostal defect. C. Creation of substernal tunnel with the pectus introducer. D. Introducer is advanced through intercostal space medial to the left pectus ridge. Upward traction is placed on the introducer to stretch intercostal muscles.
With thoracoscopic visualization, a tonsil clamp is inserted through the subcutaneous tunnel on the right side and into the pleural space to create a soft tissue defect in the intercostal muscles (thoracostomy). It is important that this defect is positioned medial to the pectus ridge because bar placement lateral to this ridge can result in intercostal muscle disruption when upward pressure is applied by the pectus introducer, and subsequent bar instability. The pectus introducer is inserted into the tunnel through this defect and, with thoracoscopic guidance, advanced beneath the sternum. While upward pressure is applied by the introducer to elevate the sternum, the blunt tip dissects the pericardium and pleura off the sternum to create a substernal tunnel. The tip of the introducer should be kept in view during the entire substernal dissection to avoid injury to the heart. If the sternal depression is too deep or the chest wall is too stiff to allow visualization of the introducer tip during this dissection, external elevation of the sternum can be achieved with mechanical retraction introduced via a subxiphoid incision. The surgeon's finger can be inserted into the subxiphoid space and used to manually guide the introducer tip beneath the sternum.
Bilateral thoracoscopy should be considered to optimize visualization of the displaced heart in the left chest. During this process, the EKG monitor is closely watched to detect evidence of arrhythmia or injury pattern. Once the mediastinum has been crossed, the introducer is advanced through the intercostal muscles of the left chest medial to the pectus ridge and into the subcutaneous/submuscular tunnel on that side. The edges of the introducer are then grasped by the surgeon and assistant and elevated to correct the sternal depression.
Once the introducer is in place in the transthoracic tunnel, the effectiveness of single bar placement can be judged visually and is indicated by complete correction of the pectus excavatum deformity on the chest wall and complete flattening of the sternum visualized thoracoscopically. If residual depression remains, creation of a second transthoracic tunnel in preparation for multiple bar placement can be undertaken at this time. Alternatively, the surgeon can proceed with pectus bar placement, and creation of a second tunnel, if necessary, can proceed after the first bar is in place. When it is obvious preoperatively that multiple bar placement will be necessary due to the nature or severity of the pectus deformity, the more cephalad transthoracic tunnel, which is usually less depressed, should be created first. The upper introducer can then be left in place to provide sternal elevation and facilitate safer dissection of the lower tunnel at the deepest point of sternal depression.
Once complete correction of the pectus deformity has been visualized with the introducer in place, preparations are made for pectus bar insertion (Fig. 17-4). A bar of appropriate length is bent into an optimal configuration to match the patient's chest wall contour. A semicircular shape with a relatively short, flat central apex (to support the sternum) flanked by gentle, convex curves on each side is used most commonly. Bars bent on the ends only with a rectangular configuration should be avoided because they typically result in undercorrection of the deformity.
Pectus bar insertion. A. Umbilical tape is advanced into the transthoracic tunnel via withdrawal of the introducer. B. The bent pectus bar is secured to the umbilical tape and pulled through the tunnel with the convexity oriented posteriorly. C. The pectus bar is rotated 180° with bar flippers.
An umbilical tape is secured through the eyelet at the tip of the introducer. Under thoracoscopic visualization, the introducer is withdrawn, and the umbilical tape is deposited in the tunnel and then secured to the pectus bar. Using thoracoscopic guidance and gentle traction on the tape, the bar is pulled into the right pleural space and through the tunnel in a convex configuration. The umbilical tape is removed, and the bar is rotated 180° using bar flippers applied on each side of the bar. With the bar in place, the sides of the pectus bar should rest comfortably against the lateral ribs and chest wall musculature. If adjustments to the bar configuration are necessary, the bar can be reflipped 180°, remodeled, and returned to final configuration without removing the bar from the tunnel.
Immediate correction of the pectus deformity should be observed after bar insertion. If there is evidence of residual sternal depression on the external chest wall or thoracoscopic visualization, placement of a second substernal bar should be undertaken.
Single bar placement inferior to the body of the sternum should be avoided. Even if this is the deepest point of depression and results in immediate correction of the deformity after bar placement, this location is unstable and carries a higher risk of bar displacement. A bar placed inferior to the sternal body (ie, subxiphoid) in combination with a second bar placed under the bony sternum is a much more stable configuration.
Bar Stabilization and Fixation
The final step of repair is bar stabilization and fixation to the chest wall to minimize the risk of bar displacement (Fig. 17-5). The current technique favored by the authors utilizes 3-point fixation, with lateral fixation provided by securing a metal rectangular stabilizer to one end of the bar (usually on the left) and placing multiple interrupted absorbable sutures through the holes in the stabilizer and bar on both sides for attachment to the underlying fascia and periosteum. Medial fixation involves attachment of the bar to underlying ribs using pericostal polydioxanone sutures (PDS) placed with the Endoclose® needle (Covidien, Norwalk, CT) through the lateral thoracic incision under thoracoscopic guidance. When multiple bars are placed, the stabilizers are typically placed on opposite sides of the chest wall to avoid overlap of the hardware on one side. Single stabilizer placement is preferred to prevent “pinching” of the ribs during future chest wall growth.
Bar stabilization and fixation. The left-sided stabilizer is secured to the bar with # 3 surgical steel wire. The right side of the bar is secured with pericostal sutures of 0 or 1 polydioxanone sutures (PDS). The lateral bar is secured with absorbable sutures placed through holes in the bar and stabilizer.
Once the pericostal sutures have been placed around the pectus bar and underlying ribs, there is no further need for thoracoscopy, and attention can be focused to evacuation of the pneumothorax. This is accomplished by cutting the insufflation tubing and placing the end of the tube under water seal. The evacuation of CO2 is facilitated by placing the patient in the Trendelenburg position with the right side elevated and administering a series of large positive pressure breaths. As the soft tissues and skin incisions are closed, progressive decrease and eventual cessation of bubbling through the tubing should be observed. The trocar can then be removed, and a chest x-ray is obtained to exclude the presence of residual pneumothorax. If bubbling persists, a chest tube should be inserted and secured in place.
The central focus of postoperative care after minimally invasive pectus repair is pain control and pulmonary toilet. The authors' current pain management regimen includes a combination of patient-controlled analgesia (PCA) with narcotic drugs, intravenous ketorolac, and muscle relaxants. Most recently, local anesthetic infusion has been continuously administered in a regional manner via bilateral thoracic On-Q® catheters (I-Flow Corporation, Lake Forest, CA). These catheters are typically placed intraoperatively and loaded prior to the initiation of pectus repair. They will infuse for 4 days postoperatively. Perioperative antibiotics are continued for 24 hours. Over the typical 4- to 5-day in-hospital postoperative recovery, patients are transitioned from intravenous to oral medications, with the expectation that they will require narcotics for an additional 2 weeks.
Physical activity is restricted after repair to minimize the risk of bar displacement. Patients are able to resume aerobic activities at 6 weeks and competitive sports at 3 months postrepair. Most patients who attend school can return in 2 to 3 weeks.
The pectus bars should remain in the chest for 2 to 4 years after repair to ensure permanent remodeling of the chest wall (Fig. 17-6). The far end of this range is appropriate for younger patients and those actively undergoing pubertal growth.
A. A preoperative photograph of a 7-year-old-boy prior to pectus excavatum repair at age 9 years. B. A postoperative photograph obtained 4 years after the surgery and 1 year after removal of the bar. (Reproduced with permission from Donald Nuss, Children's Hospital of The King's Daughters, Norfolk, VA.)
Bar removal is typically undertaken as an outpatient procedure. After induction of general anesthesia, the patient is positioned supine with both arms abducted to expose the lateral chest wall. Ideally, the previously placed hardware is palpable. If it is not, and particularly if the patient has grown considerably since bar placement, it is helpful to have fluoroscopy available to help localize the position of the bar. Positive pressure ventilation with positive end-expiratory pressure (PEEP) is maintained throughout the procedure to minimize the chance of developing a pneumothorax during the exposure and removal of the bar. Incisions through previous incision sites are preferred, and both sides of the bar should be exposed and mobilized. In some cases, heterotopic calcifications will have formed around the bar and may require dissection with osteotomes to free the bar from this encasement. The wire attaching the stabilizer and bar should be cut and removed. Both ends of the bar should be straightened using the bar flippers or Malti bender. The stabilizer can be disengaged from the bar at this point. The bar is then slowly removed with traction, using a bone hook inserted through the hole in the lateral bar. Close attention is paid to the EKG monitor during this process. Ideally, the bar is removed via the right chest incision to minimize the bar length that must pass anterior to the heart during removal. After wound closure, a chest x-ray is typically obtained in the recovery room.
One dose of cefazolin is administered immediately prior to surgery. A transverse incision is made below and well within the nipple lines. In females, particular attention is taken to place the incision within the projected inframammary crease, thus avoiding the potential complication of a breast deformity. Skin flaps are mobilized using electrocautery, primarily in the midline to the angle of Louis superiorly and to the xiphoid inferiorly (Fig. 17-7). Pectoral muscle flaps are elevated off the sternum and costal cartilages, preserving the entire pectoralis major and portions of the pectoralis minor muscle in the flap. This plane is defined by identifying the areolar plane just anterior to the costal cartilages and lateral to their junction with the sternum. An empty knife handle is used to develop this plane, and the muscle flap is then retracted anteriorly with a small right-angle retractor. Muscle dissection and elevation is carried to the costochondral junctions of the third to fifth ribs. Particular attention is paid to avoid injury to the intercostal bundles, which would result in significant bleeding.
“Open” pectus excavation repair. A. A transverse incision is placed below and well within the nipple lines at the site of the future inframammary crease. The pectoralis major muscle is elevated from the sternum along with portions of the pectoralis minor and serratus anterior bundles. B. The correct plane of dissection of the pectoral muscle flap is defined by passing an empty knife handle directly anterior to a costal cartilage after the medial aspect of the muscle is elevated with electrocautery. The knife handle is then replaced with a right-angled retractor, which is pulled anteriorly. The process is then repeated anterior to an adjoining costal cartilage. Anterior distraction of the muscles during the dissection facilitates identification of the avascular areolar plane and avoids entry into the intercostal muscle bundles. C. Subperichondrial resection of the costal cartilages is achieved by incising the perichondrium anteriorly. It is then dissected away from the costal cartilages in the bloodless plane between the perichondrium and the costal cartilage. Cutting back the perichondrium 90° in each direction at its junction with the sternum (inset) facilitates visualization of the back wall of the costal cartilage. D. The cartilages are divided at the junction of the sternum with a knife with a Welch perichondrial elevator held posteriorly to elevate the cartilage and protect the mediastinum (inset). The divided cartilage can then be held with an Allis clamp, elevated, and divided laterally, preserving the costochondral junction with a segment of costal cartilage. E. A sternal osteotomy is created above the level of the last deformed cartilage and the posterior angulation of the sternum, generally the third cartilage but occasionally the second. Two transverse sternal osteotomies are created through the anterior cortex with a Hall air drill 2 to 4 mm apart. F. The base of the sternum and the rectus muscle flap are elevated with 2 towel clips, and the xiphoid is divided from the sternum with electrocautery. This procedure allows entry into the retrosternal space. This step is not necessary when a retrosternal strut is used. Preservation of the attachment of the perichondrial sheaths and xiphoid avoids an unsightly depression that can occur below the sternum. G. With the nonstrut method the osteotomy is closed with several heavy, nonabsorbable sutures as the sternum is elevated by the assistant. H. Correction of the abnormal position of the sternum is achieved by the creation of a wedge-shaped osteotomy that is then closed, bringing the sternum anteriorly into an overcorrected position. I. The use of both retrosternal struts and Rehbein struts (David Scott Company, Framingham, MA). The Rehbein struts are inserted into the marrow cavity (inset) of the third or fourth rib and are then joined to each other medially to create a metal arch anterior to the sternum. The sternum is sewn to the arch to secure it in its new forward position. The retrosternal strut (V. Mueller, Baxter Operating Room Division, McGraw Park, IL) is placed behind the sternum and is secured to the rib ends laterally to prevent migration. J. Anterior depiction of the retrosternal struts. The perichondrial sheath to either the third or fourth rib is divided from its junction with the sternum, and the retrosternal space is bluntly dissected to allow passage of the strut behind the sternum. It is secured with 2 pericostal sutures laterally to prevent migration. Division of the perichondrial sheath immediately adjacent to the sternum avoids injury to the internal mammary vessels, which are more lateral. K. The pectoral muscle flaps are secured to the midline of the sternum, advancing the flaps to obtain coverage of the entire sternum. The rectus muscle flap is then joined to the pectoral muscle flaps. (A–H and K reproduced with permission from Shamberger RC, Welch KJ. J Pediatr Surg 1988;23:615–622. I and J reproduced with permission from Shamberger RC. In: Shields TW, ed. General Thoracic Surgery. 4th ed. Baltimore: Williams & Wilkins; 1994:538.)
Subperichondrial resection of the costal cartilages with specially designed Welch perichondrial elevators is performed by removing the third, fourth, and fifth cartilages but preserving the costochondral junctions. Occasionally the second costal cartilages are involved, particularly in older patients. Segments of the sixth and seventh costal cartilages are resected to the point where they flatten to join the costal arch, which is generally equal in length to the fourth and fifth cartilages. Familiarity with the cross-sectional shape of the medial ends of the costal cartilages facilitates their removal. The second and third cartilages are broad and flat, the fourth and fifth are circular, and the sixth and seventh are narrow and deep at their junction with the sternum.
Two parallel transverse sternal osteotomies, extending through the anterior cortex, are created using a Hall air drill (Zimmer USA, Inc, Warsaw, IN). These are placed 2 to 4 mm apart at the point where the sternum is displaced posteriorly. A short segment of the anterior cortex is then removed along with the underlying cancellous bone. This allows the sternum to be brought forward. The posterior table of the sternum is fractured behind the osteotomy by anterior elevation of the sternum. The osteotomy must be of adequate size to allow the sternum to come forward easily.
Welch would divide the rectus muscle from the tip of the sternum with electrocautery. The authors currently avoid this division because an unsightly depression at the tip of the sternum can result. If strut fixation is used, division of the rectus muscle is generally not required unless the xiphoid is protruding acutely forward. Welch would then close the sternal osteotomy with nonabsorbable sutures intentionally overcorrecting the position of the sternum 30° to 35°. While this is successful in younger children, the extent of correction is limited in older patients, leading the authors to routinely use strut fixation in these cases.
Struts can be used to hold the sternum securely forward. They are especially helpful in correcting extensive sternal rotation or severe depression. Fixation with struts is also required in all patients with Marfan syndrome or other connective tissue disorders where risk of recurrence is high. Strut fixation also avoids the need to divide the lowest 1 or 2 sets of intercostal bundles, which is required to produce adequate sternal mobility with suture fixation. Division of the intercostal bundles also contributes to the unsightly hollow at the distal end of the sternum.
Two methods of strut fixation are available. The first, employing a set of Rehbein struts, is shown in Fig. 17-7(I). The struts are placed in the marrow cavity of a rib to each side of the sternum. The arch of the struts is created anterior to the sternum and secured with stainless steel wire. The sternum is then secured to the Rehbein strut. The second technique uses a retrosternal approach as described by Adkins and Blades, and later by Jensen and colleagues. Critical to this technique is safe dissection from the 2 sides of the sternum of a path for the strut to traverse posterior to the sternum and anterior to the pericardium. It is helpful to employ a Kittner dissector to create this plane. This technique is treacherous in patients who have had prior cardiac surgery.
At the conclusion of the procedure, the wound is flooded with warm saline to remove clots. A single medium Hemovac drain (Snyder Laboratories, Inc, New Philadelphia, OH) is brought through the inferior skin flap, with the suction ports in a parasternal position to the level of the highest costal cartilage resected. The pectoralis muscle flaps are sutured to the sternum, advancing the muscles medially and inferiorly to cover the underlying sternum with muscle. The rectus muscles, if divided, are then reattached to the lower sternum medially and to the pectoralis muscles laterally. A postoperative chest radiograph is obtained in the recovery room. Perioperative antibiotics are continued with 3 postoperative doses of cefazolin. In patients of all ages, blood loss generally is well below the transfusion requirement.
The correction of pectus excavatum is technically most easily performed on young children, but recent reports have described major abnormalities of chest wall growth in children who have undergone repair at an early age. In 1990, Martinez first described a deficiency in thoracic growth in children following the repair of pectus excavatum. This was most noticeable in children operated on early in the preschool years. More recently, Haller and colleagues reported on 12 children in their teens who presented with apparent limited growth of the ribs and who had resection of the costal cartilages at an early age that had caused a bandlike narrowing of the midchest (Fig. 17-8). In some cases, the first and second ribs in which the costal cartilages have not been resected show apparent relative overgrowth, producing an anterior protrusion of the upper sternum. This occurrence has been attributed by Haller to injury during surgical repair of the costochondral junctions, which are the longitudinal growth centers for the ribs, and to decreased growth of the sternum resulting from injury to its growth centers or vascular supply. Weber and Kurkchubasche reported severe impairment of respiratory function with a restrictive defect in a 14-year-old boy after a standard repair of pectus excavatum at 4 years of age. The impairment was so severe that a sternotomy with separation of the sternal halves was performed to increase the thoracic volume and relieve symptoms.
A photograph of a 13-year-old boy who underwent pectus excavatum repair when he was 4 years old, demonstrating undergrowth of the resected costal cartilages and relative overgrowth of the upper ribs and manubrium.
Perichondrial sheaths, bone, or prosthetic material that cannot grow will form a bandlike stricture across the chest and should not be joined posterior to the sternum in a growing child. This complication of delayed thoracic growth has been described primarily in children who underwent repair in early childhood and can be avoided by delaying surgery until children are older. The complication is unique to open repair, as the Nuss procedure does not involve resection of the costal cartilages.
Preservation of the costochondral junction, leaving a segment of the cartilage on the osseous portion of the rib (Fig. 17-7D), may also minimize growth impairment. The authors delay use of the open procedure until a child is at least 10 to 12 years of age, when the chest has less remaining growth, to both minimize the risk of abnormal thoracic growth and to limit the opportunity for recurrence of the pectus excavatum.
The open surgical technique achieves excellent results in most patients (Fig. 17-9), with few and limited complications. Appropriate patient selection and timing of the procedure are critical to obtaining optimum results.
A. A preoperative photograph of a 15-year-old boy with symmetric pectus excavatum. B. Eighteen-month follow-up after the correction of pectus excavatum with Rehbein struts.