Surgical correction of pectus excavatum

Surgical correction of pectus excavatum

Surgical Correction of Pectus Excavatum By George W. Holcomb, Jr. l It has been observed that some patients who had correction of funnel chest defor...

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Surgical Correction of Pectus Excavatum By George

W. Holcomb, Jr.

l It has been observed that some patients who had correction of funnel chest deformity by methods which failed to provide fixed elevation of the involved sternal segment developed progressive sagging in later years in spite of looking good at the operating table. This has led to the adoption of a new technique of double sternal support. This procedure has resulted in 35 of 37 children (94%) being classified as excellent or satisfactory. This double support was initially established in 1959 by overlapping the upper transsected sternum while maintaining elevation of the lower end with a soft tissue sling of perichondrium and intercostal muscle. Baginning in 1961, a rigid bridge of rib or stainless steel bar was substituted at the lower end of the sternum. This has provided better support and the current preference of using the steel bar has been validated in this group of patients. The few disappointments were related to removal of the bar earlier than desired, failure to excise all the protruding sternal cartilage stumps or rib graft tips and inability to cover the lateral sternal edges

with pectoral muscles. If possible, the steel bar should not be removed before 12 mo. When these pitfalls were avoided, the results were almost uniformly excellent. The wisdom of excising all depressed cartilaginous segments, as advocated by Ravitch in 1949,4 has been substantiated. A submammary transverse incision has provided an excellent cosmetic appearance. The morbidity has been low and the mortality zero. In spite of the absence of objective evidence of cardiopulmonary dysfunction, there seems to be an almost uniform improvement in appearance and in patient activity following successful correction of the funnel chest. The latter may be as much a psychological response as a physiologic one. The low morbidity, satisfactory long term results, and general improvement in the patient’s body image and outlook on life indicate the need to offer correction of the severe pectus excavatum deformity to low risk children.

INDEX WORDS:

Pectus excavatum.

EVERAL PROCEDURES have been devised for the correction of pectus excavatum, varying from a limited operation designed to free the diaphragm from the anterior chest wall’ to a number of external and internal fixation devices.2-‘0 The use of autogenous tissue for support of the sternum in the elevated position has been advocated,” as has maintenance of the sternum in the anterior position by use of wire sutures and adhesive hemicast.12 Liberation of the sternum by division of the xiphoid, all the intercostal muscles with excision of the deformed cartilages, and a cuneiform osteotomy of the upper sternum without external fixation was proposed by Ravitch in 1949.4 Subsequently this was refined by Haller et al., I3 by the addition of tripod fixation of the upper sternum. Complete reversal of the sternum was advocated by Wada and Ikeda14

S

From the Department of Pediatric Surgery, Vanderbilr University School of Medicine. Nashville, Tenn. Presented before the 25th Annual Meeting of the Ameriran Academy of Pediatrics, Surgical Section, Chicago, Illinois, October 17719, 1976. Address for reprint requests: George W. Holcomb, Jr.. M.D., Department of Pediatric Surgery, Vanderbilt University School of Medicine, Nashville, Term. 37203. 0 1977 by Grune & Stratton, Inc. Journal of Pediatric Surgery, Vol. 12, No. 3 (June), 1977

295

GEORGE

296

W.

HOLCOMB, JR.

Fig. 1. Progressive depression of the sternum following correction of funnel chest by Ravitch procedure.

in 1972. Proponents for these procedures have, for the most part, directed attention toward mobilizing and elevating the depressed sternum. Each has been followed by varying degrees of success. The purpose of this study is to evaluate several of the previously proposed techniques and assess the operative morbidity and long term result compared to an additional method which has been developed to create a more permanent anterior position for the sternum. MATERIALS The records of 40 children the 20 years from 1956-1976.

AND METHODS

between the ages of two and 16 years have been evaluated during Boys outnumbered girls by a ratio of more than five to one. In spite Table 1. Average

Age at Operation

Follow-Up

3.8 Years Results

(Yr)

Number of CCtS.%

Ravitch

Procedure (1956-1960)

Excellent

Unsatisfactory

Satirfoctory

Second Operation

2-3

1

0

1

0

0

3-5

2

0

2

0

0

6-14

0

0

0

0

0

Upper

Sternal

Overlap

and Lower Soft-Tissue

Support

(1959-l

968)

2-3

5

2

2

1

0

3-5

0

0

0

0

0

6-14

2

1

1

0

0

16

0

0

0

0

0

0

Upper

Sternal

Overlop

and Lower Rib Graft

Support

(1961-1972)

2-3

1

1

0

0

3-5

7

4

3

0

0

6-14

2

2

0

0

0

16

0

0

0

0

0

Upper

Sternal

Overlap

and Lower Bar Support

(1965-1976)

2-3

2

2

0

0

0

3-5

11

10

1

0

0

6-14

6

5

0

1

1

16

1

0

1

0

1

27

11

2

2

Total

40

PECTUS

EXCAVATUM

297

of a large negro population in this area, none of these children had a deformity severe enough to justify operative correction. There were no significant congenital anomalies in this group. From 1956 to 1960, three patients received correction according to the technique described by Ravitch.4 Although these procedures resulted in acceptable correction, each showed progressive depression of the sternum over a 2 or 3 yr period (Fig. 1). This stimulated the desire for long term improvement with some other method. It occurred to the author that a more permanent anterior position of the sternum could be maintained if the depressed portion were fixed in an over-corrected position which would prevent progressive sagging through the years. Therefore it was decided to transsect completely the sternum in the interspace at the beginning of the depression and overlap this anterior to the fixed upper sternal segment. This construction was maintained in position with a single wire suture taken in a U fashion through both of these segments. Thus, permanent elevation for the sternum was obtained at the upper end while the lower portion initially was supported with a soft tissue sling consisting of intercostal muscles and perichondrium previously detached from the lateral edges of the sternum. Subperichondral excision of all the deformed cartilages was previously performed and the xiphoid was detached. No external fixation was used. From 1959 to 1968. seven patients were corrected using this technique (Table I). Three obtained an excellent result, three developed moderate progression of sternal depression but were judged acceptable, and one had such severe depression that he was classified as an unsatisfactory result. It became evident that additional support of the lower sternum would be beneficial in preventing progressive sagging. Thus, it was decided in 1961 to support the lower end of the sternum with an autogenous rib graft (Fig. 2F) or a stainless steel bar (Fig. 2G). The remaining 30 patients have been treated by using this rigid support beneath each end of the mobilized sternal segment. Disadvantages of the rib strut are the extra incision required with a second scar and the additional operating time. Although the rib support proved very effective, this has not been used since 1972 and currently the steel bar is preferred.

Preferred Surgical Technique A transverse submammary incision (Fig. 2A) with slight elevation in the midline has been used in every patient except one because of the improved scar which results. The one exception required a midline vertical incision because it was necessary to remove 13 segments of costal cartilage which is greater than the number usually necessary (Fig. 3A & B). This extensive dissection could not be accomplished with a transverse incision. Skin and subcutaneous flaps are elevated by dissecting beneath the superficial fascia. Mobilization of these flaps is continued down to the level of the xiphoid process and upwards to the region where the sternal depression begins. Care must be exerted not to mobilize the flaps too extensively, otherwise vascularity of the central portion may be compromised. A midline vertical incision is made through the fascia, extended to the xiphoid, and continued in an inverted Y fashion over the lowermost cartilages. By careful dissection it is possible to preserve the medial cut edges of the pectoral muscle so that these may be approximated at the conclusion of the operation to cover the sternum (Fig. 2B). Cutting into the pectoral muscle itself should be avoided and the plane of dissection should be developed on top of the costal cartilages beneath the muscle. Subperichondral resection of the depressed cartilages is accomplished beginning with the two lowermost segments. It is important to extend the dissection laterally until all of the depressed cartilage is removed. On occasions this has required resection of a short segment of rib but usually only cartilage is involved. Although the subperichondral dissection is difficult, it is thought necessary to preserve the posterior perichondrium and its attachment to the sternum so that when this is moved to the forward position regeneration will occur in the new anterior location and result in a stable, cosmetically acceptable chest wall. Also, penetration of the pleura during removal of the cartilages is less likely to occur if dissection is continued inside the posterior perichondrium (Fig. 2C). The sternal end of the cartilage is disarticulated and any bulging prominences must be trimmed. All of the remaining depressed cartilages are excised in a similar manner. This requires removal of successively shorter segments as the dissection is continued upward. Most often, excision of three to five paired cartilages is adequate. The xiphisternal junction is divided with the scalpel. The sternum is lifted forward and by using a Kitner dissector, the pleura is pushed from the undersurface of the sternum carefully to avoid

PECTUS

299

EXCAVATUM

Fig. 2 (A-G). ferred operative support.

Artist’s conception of preprocedures for double sternal

Fig. 3. A). Eight year old girl with severe sternal depression who required excision of 13 segments of cartilages for correction. g). Marked improvement postoperatively following repair which required a vertical rather than a transverse incision.

a rent. Finger dissection also aids in separating these attachments (Fig. 2D). The operator’s index finger is then inserted in the substernal space while a chisel is used to cut the sternum transversely through the interspace of the uppermost excised cartilage (Fig. 2E). The lower sternal segment is then overlapped and anchored in place anterior to the upper sternum using a U-shaped wire knot suture. An attempt should be made to partially bury the knot of the mer-

300

GEORGE

W.

HOLCOMB,

JR.

siiene or wire by scooping out a small piece of sternum with a curette to avoid this being visible beneath the skin afterwards. In younger children this suture may be taken with a needle but in the older ones it is necessary to drill two holes in each sternal segment. A ribbon retractor placed beneath the sternum during the drilling avoids injury to the heart. A rib strut (Fig. 2F) or a stainless steel bar (Fig. 2G) is then inserted beneath the sternum in the lowest interspace. Prior to placing the steel bar it is bent laterally to fit the contour of the ribs and then anchored in place with wire sutures. It is necessary to secure this supporting structure well to the ribs and sometimes, though not always, to the sternum and perichondrium in order to avoid its working loose and having to be removed too soon. After the sternum is stabilized in the overcorrected. forward position, the ends of the sternal cartilages should be trimmed so that all prominences will be eliminated. Otherwise these stumps will be visible beneath the skin of some children who have thin anterior chest walls. The overlapped sternal edge is also beveled and the periosteum and fascia which previously were separated are sutured over this prominence (Fig. 2G). Initially it was feared that this overlapped segment might result in an objectionable protrusion. Although visible in some patients, the overlapped area develops a smooth contour and no unsightly bulging has occurred. On occasions the intercostal muscle and perichondral sternal attachments just caudal to the sternal division and in some instances the lowermost sternal attachments near the xiphoid may require cutting to mobilize the sternum sufficiently to be pulled upward and overlapped. However, severance of the sternal attachments should be avoided except where necessary to accomplish the overlap, The posterior perichondrium which remains attached to the sternum is pulled anteriorly with it, and regeneration of the cartilages occurs in this forward position. The rectus muscle and xiphoid are then sutured to the sternum and Iowest intercostal bundles. The xiphoid is not excised but is allowed to drop a little posteriorly, otherwise this might later become prominent and unsightly. There is no fear that reapproximation of the rectus muscles and xiphoid in this location will exert a downward pull on the sternum and lead to a recurrence of the depression as might occur when a rigid sternal support is not used. It is important to avoid excision of the xiphoid and a space at the site of its previous attachment to the sternum. or herniation may occur. A secondary operation was required in the oldest patient because of this complication. Usually the pectoral muscle is easily sutured over the sternum in the midline, particularly if it was previously elevated with care. However, if the muscle cannot be stretched to do this then it should be sutured to the periosteum of the sternum at least to cover the lateral edges. If this is not done or if there is congenital deficiency of pectoral muscle then a lateral sulcus may result. This occurred in one of our patients and may require a secondary procedure with implantation of a silastic mold to improve the chest contour. The superficial fascia is then approximated with interrupted Dexon and the skin with interrupted sutures or with continuous subcuticular pull-out 4.0 nylon. This latter suture is left in place for 2-3 wk. Attention to the details of avoiding an unsightly scar has been appreciated by the patients and parents. Establishment of hemovac suction to the substernal space for two to three days has proved helpful in preventing accumulation of fluid in the mediastinum as well as beneath the skin flaps. Unless the pectus bar becomes loosened early, it is left in place at least 9 and preferably I2 mo. A short incision at either end of the scar usually allows easy removal of the bar. The rib support does not require removing when it is used.

RESULTS

All of the operations were performed by the author, who has also followed the patients postoperatively. Evaluation of the results was by follow-up examination for those who live in the area, and by parent evaluation supported by letter for the patients who had moved from the community. This follow-up allows separation of results into three distinct groups: excellent, satisfactory, and unsatisfactory (Table 1). In those considered to have an excellent result, the anterior chest wall no longer had a sternal depression and had a normal or near-normal contour with a cosmetically acceptable scar. The satisfactory group consisted of those patients who had either mild retraction of the sternum or the cartilagenous sternal stumps, the lateral sternal edges, or the rib graft ends bulged slightly beneath the skin. Unsatisfactory results were obvious

PECTUS

EXCAVATUM

301

recurrences or simply ajudged disappointments either to the family or to the surgeon, although there was some improvement over the initial condition. The operative procedure was tolerated well in all patients and there were no significant complications. Blood transfusions were administered to 11 children earlier but this has not been necessary since 197 1. A small hole was made in the pleura in only five instances. Water seal drainage was used in two children and the rent was sutured in the other three. Tracheostomy was not necessary and no patients required mechanical ventilation postoperatively. Atelectasis and postoperative pneumonia occurred in only a few instances and were transient in nature. Mediastinitis did not occur. Antibiotics were used only for specific indications, not routinely. There were no wound infections. Skin separation occurred in the mid portion of one of the earliest patients due to excessive elevation of the skin flaps with interruption of vascular supply. A secondary closure of this wound provided a satisfactory result. Caution was exercised in the remaining children in order to avoid this complication. Secondary operation was required in two patients, one following the need for early removal of the bar from trauma, who later was involved in an automobile accident with injury to the anterior chest. The other secondary procedure followed excision of the xiphoid process and separation of the rectus muscles from the inferior sternum with a hernia. In several instances the metal bar became dislodged either from trauma or from the sutures working loose. If the bar required removal earlier than desired, it was considered a distinct advantage to have the upper end of the sternum supported in the forward position by the overlap procedure to prevent progressive sagging. This proved effective in five children who required removal of the bar within I-3 mo following the operation. Best results may be expected by correcting this deformity between the ages of 2-10 yr. Hospitalization required an average of eight days. From 1959-1976,37 children have had the double sternal support procedure performed. Of this group, 27 (73:;) were considered to have an excellent result, 8 (21’,,) were satisfactory, and 2 (60,) were unsatisfactory. Five of the satisfactory group were prevented from being classified as excellent because of visible protrusion of a sternal cartilagenous stump, protruding rib graft tip or bulging lateral sternal border due to lack of pectoral muscle coverage. One was unsatisfactory because he fell down the steps one month following the operation and dislodged the sternal bar requiring early removal. This is the patient referred to earlier who later was involved in an automobile accident with chest injury: reoperation was required. The other unsatisfactory result followed the use of soft-tissue support of the lower sternum which proved inadequate and the xiphisternal depression recurred. The longest follow-up period was for 20 yr and the entire group averaged 3.8 yr. Long term follow-up is necessary to assess any pectus repairs, particularly those procedures which totally mobilize the sternum and do not provide a permanent and rigid support. It is this group which will very likely develop a recurrence, particularly during adolescent growth. REFERENCES I. Brown AL: Pectus excavatum (funnel chest). .I Thorac Surg 9: 164, 1939 2. Welch KJ: Satisfactory surgical correction

of pectus excavatum deformity in childhood. J Thorac Surg 36:697, 1958 3. Rehbein F, Wernicke HH: Operative

302

treatment 5, 1957

GEORGE

of funnel

chest.

Arch

Dis Child

32:

4. Ravitch MM: Operative treatment of pectus excavatum. Ann Surg 129: 429, 1949 5. Daniel RA: Surgical treatment of pectus excavatum. J Thorac Surg 35:719, 1958 6. Gross RE: Surgery of Infancy and Childhood. Philadelphia, W. B. Saunders Co., 1953 7. Adkins PC, Blades B: Stainless steel strut for correction of pectus excavatum. Surg Gynecol Obstet Il3:l I I. 1961 8. May AM: Operation for pectus excavatum using stainless steel wire mesh. J Thorac Cardiovasc Surg 42: 122, 196 1 . 9. Mayo

P, Long

GA:

Surgical

repair

of

W.

HOLCOMB,

JR.

pectus excavatum by pin immobilization. J Thorac Cardiovasc Surg 44:53, 1962 10. Peters RM. Johnson G: Stabilization of pectus deformity with wire strut. J Thorac Cardiovasc Surg 47:8 14, 1964 11. Brantigen OC: Pectus excavatum. Dis Chest 521667. 1967 12. Dafoe CS, Ross CA: Surgical treatment of pectus excavatum utilizing an adhesive hemicast. Dis Chest 40:479, 1961 13. Haller JA. Peters GN. Mazur D et al: Pectus excavatum. J Thorac Cardiovasc Surg 60:375, 1970 14. Wada J, lkeda K: Clinical experience with 306 funnel chest operations. Int Surg 57: 707, 1972