Chest and abdominal injuries caused by seat belt wearing.

Abstract: The authors report an original case of seat belt syndrome. Sternal fractures are common in patients with seat belt injuries. Its association with blunt bowel trauma is rarely related in the literature. Distracted injury has contributed to delay the diagnosis of intestine injury. The presence of a seat belt sign must lead to the consideration of occult injuries especially abdominal. Close observation and serial examination should be the rule.

Key Words: seat belt syndrome, sternal fracture, blunt bowel trauma

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Seat belt use has been mandatory in France since 1973 for front seat passengers, and since 1990 for the rear seat. This compulsory measure has contributed to a decrease in the risk of injuries in road traffic collisions. (1) However, during the last 30 years, several publications have examined injuries resulting from seat belt use. This restraint system is associated with a specific pattern of injuries such as sternal fracture, bowel trauma (2) or lumbar spine injuries, (3) which has been categorized as seat belt syndrome.

We report a case associating sternal fracture with blunt bowel trauma related to seat belt use which, to our knowledge, has not been described previously.

Case Report

A 22-year-old man was the front passenger in a car involved in a head-on collision. Upon arrival at the emergency department, he was alert, but complained of severe middle thoracic pain, which required IV opiate administration. His heart rate was 100/min, blood pressure 120/75 mm Hg and Glasgow coma scale was 15. Respiratory rate was 22 breaths/min and oxygen saturation was 98% on air room. The physical examination revealed a diagonal ecchymosis across the chest and a transverse abdominal abrasion. The intensity of the pain resulting from the sternal fracture made abdominal examination difficult to perform. The electrocardiograms at admission and on the subsequent days revealed an incomplete right bundle branch block. The initial chemistry was unremarkable. The cardiac markers were not consistent with myocardial contusion. Chest x-ray showed clear lung fields. Lateral radiography of the sternum revealed a transverse fracture of the body with displacement. The patient wasadmitted to the intensive care unit for close observation. Positive peritoneal signs became evident on the second day, and abdominal palpation revealed an increase in tenderness. A CT scan was performed and a bowel injury was diagnosed. The patient underwent a laparotomywhich revealed a tear of the jejunum and mesenteric contusion. The postoperative period was unremarkable.

Discussion

The increase in road traffic accidents and the seat belt compliance rate contribute to higher rates of injuries resulting from seat belt use. Chest and/or abdominal abrasion at the site of seat belt contact are commonly seen, and with the exception of subcutaneous bruising, the sternal fracture is the most common seat belt injury.

Sternal fractures are seen with increasing frequency in motor vehicle accidents, especially since the introduction of seat belt legislation. Since that time, the incidence of sternal fractures has increased threefold. (4)

Clinical manifestations include pain and tenderness over the sternum. In the setting of a sternal fracture, myocardial contusion is strongly feared, but fortunately, rare. Conductance or excitability disturbance must lead to monitoring in the intensive care unit. Usual associated injuries are spinal trauma and rib fractures. (2,3) The association of sternal fracture with bowel injury has not been frequently reported in the literature.

There has, however, been a significant increase in the incidence of intestinal injuries among seat belt users. Early clinical manifestation of injuries of the bowel and mesentery may be poor. (5) Signs of peritonitis and abdominal pain may be absent on initial evaluation, (5) especially since the physician may be distracted by the pain of extra-abdominal injuries, such as sternal fracture, as in our case. Association of blunt bowel trauma with sternal fracture is uncommon. Frick et al (6) reported no sternal fracture associated with blunt bowel injury in a study of 70 cases. The presence of a seat belt abrasion across the abdomen is an argument for high suspicion, but may not be necessarily indicative of intestinal injury. (7) Chandler et al (7) reported the presence of an abdominal seat belt sign in 14/117 cases. Of these 14, two-thirds had an abdominal injury. In addition, the seat belt sign may be found in victims without occult injuries. Conversely, its absence cannot exclude underlying visceral injury. According to some authors, the presence of a seat belt sign requires admission of the patient and serial examination. Increasing abdominal tenderness is the most frequent change after the initial evaluation which leads to surgical intervention. (6) Delayed diagnosis of bowel injuries could result in higher mortality and morbidity. (8)

Conclusion

Sternal fracture can be associated with hollow organ injury. Emergency physicians should keep in mind that seat belt syndrome can include thoracic and abdominal injury. The abdominal examination may be unreliable because of the presence of associated extra-abdominal injuries. Bowel injury must be suspected systematically even in the absence of clinical manifestation. The presence of an abdominal seat belt sign is an argument for intestinal injury.

References

1. Crandall CS, Olson LM, Sklar DP. Mortality reduction with air bag and seat belt use in head-on passenger car collisions. Am J Epidemiol 2001; 153:219-224.

2. Arajarvi E, Santavirta S, Tolonen J. Abdominal injuries sustained in severe traffic accidents by seatbelt wearers. J Trauma 1987;27:393-407.

3. Jones HK, McBride GG, Mumby RC. Sternal fractures associated with spinal injury. J Trauma 1989;29:360-364.

4. Budd JS. The effect of seat belt legislation on the incidence of sternal fractures seen in the accident department. BMJ 1985;291:785.

5. Asbun H, Irani H, Roe EJ, et al. Intra-abdominal seatbelt injury. J Trauma 1990;30:189-193.

6. Frick EJ Jr, Pasquale MD, Cipolle MD. Small-bowel and mesentery injuries in blunt trauma. J Trauma 1999;46:920-926.

7. Chandler CF, Lane JS, Waxman KS. Seatbelt sign following blunt trauma is associated with increased incidence of abdominal injury. Am Surg 1997;63:885-888.

8. Fakhry SM, Brownstein M, Watts DD, et al. Relatively short diagnostic delays (<8 hours) produce morbidity and mortality in blunt small bowel injury: an analysis of time to operative intervention in 198 patients from a multicenter experience. J Trauma 2000;48:408-414.

Success is falling nine times and getting up ten.
--Jon Bon Jovi

J. L. Greingor, MD and S. Lazarus, MD

From the Emergency Department, CHR METZ-1, pl. Ph. De Vigneulles, 57038 Metz, France.

Reprint requests to J. L. Greingor, 35, rue de la folie, 57050 Metz, France. Email: [e-mail]

Accepted January 3, 2006.

RELATED ARTICLE: Keys Points

* Association of blunt bowel trauma with sternal fracture is uncommon.

* The presence of a seat belt abrasion across the abdomen is an argument for high suspicion, but may not be necessarily indicative of intestinal injury.

* Bowel injury must be suspected systematically even in the absence of clinical manifestation.