Seat Belt–Related ChondrosternalDisruption With Lung HerniationDavid Rice, MB, BCh, Naveen Bikkasani, MD,Raphael Espada, MD, Kenneth Mattox, MD,and Matthew Wall, MD

Divisions of Cardiothoracic Surgery and Trauma and CriticalCare Service, and Department of Radiology, Ben TaubGeneral Hospital and Baylor College of Medicine, Houston,Texas

A case of blunt chest trauma resulting in anterior chon-drosternal separation with right lung herniation andhemothorax is presented. The injury is related to the useof a seat belt restraint. The patient underwent surgicalrepair with polytetrafluoroethylene chest wall recon-struction. Postoperative recovery was complicated byrespiratory insufficiency due to underlying pulmonarycontusion and multiple rib fractures.

(Ann Thorac Surg 2002;73:1950–1)© 2002 by The Society of Thoracic Surgeons 5

Seat belt–related injuries have been well characterizedand predominately involve the intraabdominal or-

gans. Significant injury to the chest wall, cervical vascu-lature, and intrathoracic structures is infrequent, how-ever. We report a case of severe chest wall injury withresulting lung herniation after a motor vehicle accident inwhich the driver was restrained.

A 54-year-old 270-lb male was a restrained driver in arollover motor vehicle accident at highway speeds. Emer-gency room evaluation revealed that he was hemody-namically stable and had no evidence of neurologicalinjury but was in respiratory distress. A linear superficialskin abrasion extended diagonally from the left clavicleacross his right chest. Breath sounds were diminished onthe right side. His right pectoral region was tender,fluctuant to palpation, and slightly depressed. Because ofincreasingly labored breathing, he underwent endotra-cheal intubation. Chest roentgenogram revealed bothlungs expanded with an area of hyperlucency in the rightmedial basal zone. Chest computed tomography (CT)showed the presence of multiple right-sided rib frac-tures, a right hemothorax, and a large herniation of theright lung through the anterior chest wall at the rightparasternal region (Fig 1). Head and abdominal CT andarch aortography were negative. He subsequently under-went operative intervention.

At surgery, a midline skin incision was made and wasextended in a right inframammary direction. The rightpectoralis major muscle was elevated from the chest walland the underlying defect and hernia cavity were ex-

posed. The herniation occurred through the pectoralismajor muscle with a defect in the fascia and extended ina cephalad manner into the subcutaneous tissues. Therewas fracture of the second through the sixth costalcartilages, the majority occurring at the chondrosternaljunctions with resultant chondrosternal separation. Thefifth and sixth costal cartilages had multiple fractures. Inaddition, there were fractures of ribs 3 through 7 alongthe anterior axillary line. Remarkably, the right internalmammary artery was intact. The herniated lung ap-peared normal and was easily reduced back into thechest cavity. After thorough exploration of the right chestand evacuation of a 500-mL hemothorax, the defect wasrepaired by securing a polytetrafluoroethylene meshbetween the ends of the ribs, laterally and the rightsternal border, medially. This was accomplished by dril-ling holes in the lateral border of the sternum using ahigh-speed pneumatic drill and passing interrupted su-tures of no. 1 polypropylene through the holes into themesh. The fractured ends of the costal cartilages werereapproximated over the mesh using no. 1 braided poly-ester suture to facilitate their healing.

Postoperatively, the patient required prolonged venti-latory support. His chest roentgenograms showed wors-ening of his pulmonary contusion and his course wascomplicated by development of a staphylococcal pneu-monia. Ultimately, he was extubated after 18 days. Hehas continued to do well and has no functionallimitations.

Comment

Traumatic lung herniation is rare and there are fewerthan 300 cases reported in the literature. Herniation maybe the result of either penetrating or blunt injury to thechest wall. In cases of blunt trauma, herniation typicallyoccurs in the parasternal region, perhaps related to thefact that the external intercostal muscles are absent inthis area. Widespread usage of three-point safety re-straint systems in automobiles has lead to recognition ofa spectrum of seat belt–related injuries. Although thesetypically involve injury to the intraabdominal organsfrom the lap belt, shoulder harnesses have been impli-

Accepted for publication Nov 6, 2001.

Address reprint requests to Dr Rice, Department of Thoracic and Cardio-vascular Surgery, The University of Texas M. D. Anderson Cancer Center,1515 Holcombe Blvd, Box 445, Houston, TX 77030-4009; e-mail:drice@mdanderson.org.

Fig 1. Computed tomography of chest showing right lung hernia-tion, right rib fracture, and right hemothorax.

1950 CASE REPORT RICE ET AL Ann Thorac SurgTRAUMATIC LUNG HERNIA 2002;73:1950–1

© 2002 by The Society of Thoracic Surgeons 0003-4975/02/$22.00Published by Elsevier Science Inc PII S0003-4975(01)03506-8

cated in chest injury, most commonly sternal fracture [1].There have been at least four other reports documentingsevere chest wall injury with lung herniation in re-strained drivers [2–5]. In three of these, as in our report,the victim was obese. It has been postulated that theshoulder harness provides relatively greater stabilizationof the left chest while allowing a shearing force to beapplied across the right chest wall at times of suddendeceleration. Whether or not patients of greater massapply more decelerating force to their chest wall isunknown.

In this case, although a flail chest was obvious, thediagnosis of lung hernia was not arrived at until thepatient had undergone chest CT. The findings of chestwall deformity, pain, fluctuance, and crepitance may beequally present in cases of chest wall injury with pneu-mothorax and subcutaneous emphysema, an occurrencethat is significantly more common than lung herniation.Standard antero-posterior chest roentgenograms, al-though suggestive, are rarely diagnostic, and obliqueviews are not routinely obtained in most emergencycenters. Therefore, chest CT scanning will likely remainthe most efficient diagnostic modality for lung herniation.Because the condition is rare and infrequently consid-ered, there have been a number of reports of patientswho did not receive CT scans as part of their initialevaluation, where the diagnosis of lung herniation wasdelayed [4, 6]. Therapeutic decisions must distinguishbetween spontaneous and congenital lung hernias andthose due to trauma. The former are typically asymptom-atic and conservative treatment may be advocated [7, 8].In general, all lung hernias due to penetrating traumashould undergo surgical repair, and it is strongly recom-mended in cases where there is evisceration of pulmo-nary parenchyma [9]. Most authors recommend opera-tive intervention for herniation secondary to blunt injury,although small asymptomatic hernias could conceivablybe followed with close observation [8]. There is a theo-retical risk of incarceration and devitalization [9], al-though the incidence of this occurrence appears to beextremely rare. The principles of surgical correction arethose of any hernia repair, namely, the reduction of thehernia and the buttressing of the defect. Although directrepair of the chest wall defect may be occasionallyperformed [2, 5], most authors have reported using somesort of intrathoracic prosthetic patch, most commonlypolytetrafluoroethylene [3, 4, 6, 10], Vicryl (Ethicon, Som-erville, NJ) [8], or polypropylene mesh [11]. There havebeen two reports of successful hernia repair using video-assisted thoracoscopic techniques [6, 11]. Ultimate out-come after repair of lung hernias depends on the extentof the underlying parenchymal contusion and on thepresence of other concomitant injuries. In the case out-lined above, the patient had severe respiratory compro-mise related to pulmonary contusion, multiple rib frac-tures, and subsequent pneumonia. As in all cases of chestwall injury, rigorous postoperative chest physical therapyand excellent pain control are imperative.

In summary, traumatic lung herniation is a rare injury.The association with seat belt usage is well described,and obesity may possibly be a cofactor. Most injuries willrequire operative intervention, which usually requires

buttressing of the chest wall defect with prosthetic mesh.The extent of parenchymal contusion, chest wall instabil-ity, and associated injuries are the major factors influenc-ing recovery.

References1. Arajarvi E, Santavirta S. Chest injuries sustained in severe

traffic accidents by seat belt wearers. J Trauma 1989;29:37–41.2. May A, Chan B, Daniel T, Young J. Anterior lung herniation:

another aspect of the seat belt syndrome. J Trauma 1995;38:587–9.

3. Cernilia J, Lin J, Ott R, Scannell G, Waxman K. A techniquefor repair of traumatic parasternal lung herniation: casereport. J Trauma 1995;38:935–6.

4. Jacka M, Lusion F. Delayed presentation of traumaticparasternal lung hernia. Ann Thorac Surg 1998;65:1150–1.

5. Allen G, Fischer R. Traumatic lung herniation. Ann ThoracSurg 1997;63:1455–6.

6. Reardon M, Fabre J, Reardon P, et al. Video-assisted repairof a traumatic intercostal pulmonary hernia. Ann ThoracSurg 1998;65:1155–7.

7. Glenn C, Bonekatdo W, Cua A, et al. Lung hernia. Am JEmerg Med 1997;15:260–2.

8. Francois B, Desachy A, Cornu E, et al. Traumatic pulmonaryhernia: surgical versus conservative management. J Trauma1998;44:217–9.

9. Bowley D, Bradford K. Penetrating lung hernia with pulmo-nary evisceration: case report. J Trauma 2001;50:560–1.

10. Filosso P, Oliaro A, Donati G, et al. Post-traumatic hernia ofthe lung. Eur J Cardiothorac Surg 2001;19:360.

11. Brown W, Hauser M, Keller F. Hernia of the lung repaired byVATS: a case report. J Laparoendoscopic Surg 1996;6:427–30.

Incidental Finding ofMyeloproliferative DisordersDuring SternotomyMaher E. Deeb, MD, Yaron Shargal, MD,Gideon Merin, MD, and Eli Milgalter, MD

Department of Cardiothoracic Surgery, Hadassah MedicalCenter, Hebrew University, Jerusalem, Israel

We report 2 cases of myeloproliferative disorders discov-ered incidentally at the time of routine coronary bypasssurgery. Suspicion of abnormal bone marrow tissue uponperforming sternotomy and subsequent sampling forfrozen section made the diagnosis. The surgical plan waschanged, and partial revascularization without cardio-pulmonary bypass was performed.

(Ann Thorac Surg 2002;73:1951–2)© 2002 by The Society of Thoracic Surgeons

A myeloproliferative disorder (MPD) was incidentallydiscovered in 2 patients during routine sternotomy

for coronary bypass operation (CABG). This disorder isextremely rare, and usually expresses the existence ofsystemic disease.

Accepted for publication Aug 7, 2001.

Address reprint requests to Dr Milgalter, Department of CardiothoracicSurgery, Hadassah Medical Center, P.O.B 12000, Jerusalem 91120, Israel;e-mail: milgalter@hadassah.org.il.

1951Ann Thorac Surg CASE REPORT DEEB ET AL2002;73:1951–2 MPD FOUND DURING STERNOTOMY

© 2002 by The Society of Thoracic Surgeons 0003-4975/02/$22.00Published by Elsevier Science Inc PII S0003-4975(01)03627-X