Document Type : Review
Department of Emergency Medicine, Imam Reza Hospital, School of medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Blunt chest trauma accounts for the majority of mortalities and morbidities in traumatized patients. Rib fractures are one of the most common chest wall injuries due to blunt chest trauma, which is estimated to occur in 10% of all traumatic injuries. Conventional radiography and ultra-sonography are two commonly methods used for rib fractures diagnosis with different accuracy. In this study, we described different methods used in diagnosis of injuries related to blunt chest trauma and we aimed to review several studies compared the diagnostic value of these methods.
Blunt chest trauma accounts for the majority of thoracic injuries (81% in children and 78% in elderly) which are known as the 3rd most common injuries in patients with multiple traumas. The incidence of thoracic trauma in multi trauma situations significantly raises the mortality rate, which is responsible for almost 25% of death in traumatic patients (1). The blunt chest trauma includes chest wall injuries (bony and soft tissues), intra-pleural lesions, lung, and mediastinal injuries. Rib fractures without any associated complication are considered as minor blunt chest trauma.
Rib fracture is one of the most common type of chest wall lesions due to blunt chest trauma and almost occurs in 10% of all traumatic injuries (2). Rib fractures can be associated with delayed mortality or wide range of morbidity; from a single injury to life-threatening complications (hemothorax, pulmonary contusion, hypoventilation, hypocapnia, hypoxia, atelectasis, pneumonia, cardiovascular injury and etc.). Motor vehicle accidents are the major cause of blunt chest trauma and the consequent rib fractures (63-78%).
Severe complications may occur following blunt chest trauma even with no rib fracture evidence. Due to significant contribution of rib fracture in increasing the morbidity and mortality rate, accurate diagnosis of injuries is a clinical priority. Localization of the rib fracture can be indicative of related injured organ. The incidence of first and second rib fractures is rare and these fractures may lead to life-treating multisystem injuries of spine, lungs, aorta, and vascular system. Injured spleen and liver may happen through lower left and right rib fractures, respectively (3). It has been agreed that the severity of rib fractures consequences has a linear relation with age, ossification level of chest wall, and the number of fractures. Sirmali et al. concluded that appearance of 3 or more fractures in patients, necessities the patient hospitalization and follow-up for pulmonary complications (4).
Children of 0-3 years have flexible ribs that can result in lower incidence of rib fractures compared with adolescents (5). Child abuse is another possible cause for most of the rib fractures in children in addition to motor vehicle accidents (6). It has been reported that in patients younger than 45 years, similar to elderly, 4 or fewer rib fractures could be related with increased risk of severe pulmonary or non-pulmonary complications, or death (7).
Considering the mechanism of injury and the clinical signs (breath sounds and crepitation, thorax instability, dyspnea, pain, cyanosis, etc.) can help better diagnosis of trauma and related injuries. Simple chest X-ray (CXR), high frequency ultrasonography, and computed tomography are common methods for rib fracture diagnosis in patients with blunt chest trauma.
Conventional radiography is usually the first step imaging assessment of blunt chest trauma and complications that may need immediate treatments. Radiography of suspected rib fracture patients should be done with postero-anterior (PA), and oblique projections. the patient position and duration of inspiration are important in conventional radiography (8). In some studies, screening with conventional radiography has resulted in normal radiographs with some missed rib fractures or complications. Undetected injuries could be the major cause of mortality and morbidity due to blunt trauma (9,10). So, conventional radiography is not recommended as the best method for the evaluation of thorax bony structures (11).
Routinely, using chest radiographs might have some limitations in providing accurate assessment in situations such as radiography from the obese or older patients with osteoporosis, minor rib fractures, greenstick fractures, cartilage and costochondral separations.
Computed tomography (CT)
Although CT is not used for the diagnosis of rib fractures, it represents the most accurate data about the number and location of rib fractures and internal related injuries of traumatized patients. CT has advantage to radiography in detection of cartilage fractures which are usually missed by radiography (12). Due to the risk of several internal injuries in first rib fracture situation, CT is suggested to be used for an early diagnosis of fracture in patients with severe thoracic blunt trauma. In the study of Exadaktylos et al. more than 50% of normal conventional radiographs revealed severe injuries following CT scans; 8% of them showed lethal aortic injuries. Based on high accuracy, decreased scanning duration, and ease of use, CT is strongly recommended to be applied routinely after initial assessment of patients for chest blunt trauma diagnosis. In these studies, it is recommended to use conventional radiography only for the follow-up period (13).
Based on several studies, CT is more effective and accurate than conventional radiography in detecting internal injuries of the pleural space (pneumothorax, hemothorax) (14,15), lungs (lung herniation, pulmonary contusion, and laceration) (16,17), airways (bronchial and tracheal lacerations, and esophagus injuries) (18-20), pericardial space, heart valves and chambers, vascular system, diaphragm (21-24), chest wall (rib, scapula, and sternal fractures, sternoclavicular dislocation, flail chest) (25-27).
This is a highly sensitive method, which is increasingly used in the process of blunt chest trauma assessment. Ultrasound (US) is a non-invasive diagnostic method used for diagnosis of pulmonary, pleural, mediastinal diseases, or in emergency conditions (28). In comparison with other diagnostic methods, US has higher sensitivity than conventional radiology and in contrast with CT, it is a non-invasive method which does not use radiation or any radio-contrast agents and can be applied at any time or place for patients at any age, during pregnancy period, or renal damages. Rib fractures as the most common resultant of blunt chest trauma can be visualized through sonography procedure. In this review, we collected studies compared the efficacy of US and radiology in rib fracture diagnosis.
According to Hurley et al. presence of localized pain, plural effusion, pneumothorax, cortical discontinuities, acoustic shadows, reverberation artifacts, and hematoma by ultrasonography can be proposed as the diagnostic criteria for detecting the fractured ribs (29).
Application of radiography and ultrasonography in rib fracture diagnosis has been compared in different studies. Information of the mentioned studies is summarized in Table 1.
Majority of studies have obtained great discrepancy between detection rate of ultrasound and plain radiography and have proposed sonography as the more sensitive method than the conventional radiography in rib fractures detection. Contrary with others, in the study of Hurely et al. with the smaller studied group, ultrasound was not proposed as the gold standard method and its application revealed low superiority to the plain radiography in rib fraction diagnosis. Hurely et al. proposed ultrasound as a time-consuming and painful method which was not comfortable to be performed on traumatized patients with pain and was associated with limited access of transducer to thorax areas such as upper ribs (29-32). In the study of Kara et al. (33), older patients showed higher incidence of bony rib fractures and the frequency of the chondral rib fractures were higher in younger patients. In this study, there was not any significant relation between age, gender, duration of pain, and site of trauma to the prediction of rib fracture.
In considered studies, conventional radiography does not have the capability to detect the costochondral and chondrosternal cartilage fractures which implies the need for more sensitive diagnostic methods (33,34). Kara et al. also mentioned that obesity and large breasts are factors that reduce the quality of ultrasonography diagnosis and US is not able to visualize the subscapular ribs and the infraclavicular parts of the ribs (33).
In the study of Griffith et al. ultrasonography revealed 10 times more fractures and 6 times more patients with fractures than radiography. Using higher resolution transducer and low weight patients have been proposed to be related with higher detection rate of ultra-sonography than conventional radiography (32). Bitschnau et al. in 1996, diagnosed the rib fracture in 58% of total patients through ultrasound and in 30% of total patients through plain radiography; almost 2 times as many patients in ultrasound as radiography (31).
According to literature, conventional radiography is not reliable as a sole method in rib fractures diagnosis process. In most of the studies, ultrasonography has showed more sensitivity than conventional radiography, more accessibility, and no radiation compared with computed tomography, which is recommended to be used routinely in patients suspected of rib fractures.
The acceptable practice of rib fracture detection is recommended to start with the evaluation of the event history, performing clinical examinations, using plain radiography, and eventually ultrasound for detecting the fractures which was not observed through conventional radiography. Based on compared studies, ultrasound has not been proposed as the universal gold standard technique to be used routinely in rib fracture diagnosis. Further studies are required to obtain the most comprehensive data on diagnostic value of ultra-sonography.
We would like to thank Clinical Research Development Center of Ghaem Hospital for their assistant in this manuscript. This study was supported by a grant from the Vice Chancellor for Research of the Mashhad University of Medical Sciences for the research project as a medical student thesis with approval number of 910358.
Conflict of Interest
The authors declare no conflict of interest.
- Kaewlai R, Avery LL, Asrani AV, et al. Multidetector CT of blunt thoracic trauma. Radiographics. 2008;28:1555-1570.
- Ziegler DW, Agarwal NN. The morbidity and mortality of rib fractures. J Trauma. 1994;37:975-979.
- Middleton C, Edwards M, Lang N, et al. Management and treatment of patients with fractured ribs. Nurs Times. 2003;99:30-32.
- Sirmali M, Turut H, Topcu S, et al. A comprehensive analysis of traumatic rib fractures: morbidity, mortality and management. Eur J Cardiothorac Surg. 2003;24:133-138.
- Crankson SJ, Fischer JD, Al-Rabeeah AA, et al. Pediatric thoracic trauma. Saudi Med J. 2001;22:117-120.
- Berdon WE, Feldman KW. A modest proposal: thoracic CT for rib fracture diagnosis in child abuse. Child Abuse Negl. 2012;36:200-201.
- Testerman GM. Adverse outcomes in younger rib fracture patients. South Med J. 2006;99:335-339.
- Danher J, Eyes BE, Kumar K. Oblique rib views after blunt chest trauma: an unnecessary routine? Br Med J (Clin Res Ed). 1984;289:1271.
- Wootton-Gorges SL, Stein-Wexler R, Walton JW, et al. Comparison of computed tomography and chest radiography in the detection of rib fractures in abused infants. Child Abuse Negl. 2008;32:659-663.
- Traub M, Stevenson M, McEvoy S,et al. The use of chest computed tomography versus chest X-ray in patients with major blunt trauma. Injury. 2007;38:43-47.
- Carpenter AJ. Diagnostic techniques in thoracic trauma. Semin Thorac Cardiovasc Surg. 2008;20:2-5.
- Malghem J, Vande Berg B, Lecouvet F, et al. Costal cartilage fractures as revealed on CT and sonography. AJR Am J Roentgenol. 2001;176:429-432.
- Exadaktylos AK, Sclabas G, Schmid SW, et al. Do we really need routine computed tomographic scanning in the primary evaluation of blunt chest trauma in patients with “normal” chest radiograph? J Trauma. 2001;51:1173-1176.
- Mayberry JC. Imaging in thoracic trauma: the trauma surgeon’s perspective. J Thorac Imaging. 2000;15:76-86.
- Miller LA. Chest wall, lung, and pleural space trauma. Radiol Clin North Am. 2006;44:213-224.
- Wagner RB, Crawford WO Jr, Schimpf PP. Classification of parenchymal injuries of the lung. Radiology. 1988;167:77-82.
- Wanek S, Mayberry JC. Blunt thoracic trauma: flail chest, pulmonary contusion, and blast injury. Crit Care Clin. 2004;20:71-81.
- Chen JD, Shanmuganathan K, Mirvis SE, et al. Using CT to diagnose tracheal rupture. AJR Am J of Roentgenology. 2001;176:1273-1280.
- Wintermark M, Schnyder P. The Macklin effect: a frequent etiology for pneumomediastinum in severe blunt chest trauma. Chest. 2001;120:543-547.
- Strauss DC, Tandon R, Mason RC. Distal thoracic oesophageal perforation secondary to blunt trauma: case report. World J Emerg Surg. 2007;2:8.
- Fulda G, Brathwaite CE, Rodriguez A, et al. Blunt traumatic rupture of the heart and pericardium: a ten-year experience (1979-1989). J Trauma. 1991;31:167-172.
- Pretre R, Chilcott M. Blunt trauma to the heart and great vessels. N Engl J Med. 1997;336:626-632.
- Mirvis SE, Shanmuganathan K. Diagnosis of blunt traumatic aortic injury 2007: still a nemesis. Eur J Radiol. 2007;64:27-40.
- Shanmuganathan K, Killeen K, Mirvis SE, et al. Imaging of diaphragmatic injuries. J Thorac Imaging. 2000;15:104-111.
- Barnea Y, Kashtan H, Skornick Y, et al. Isolated rib fractures in elderly patients: mortality and morbidity. Can J Surg. 2002;45:43-46.
- Weening B, Walton C, Cole PA, et al. Lower mortality in patients with scapular fractures. J Trauma. 2005;59:1477-1481.
- Wedde TB, Quinlan JF, Khan A, et al. Fractures of the sternum: the influence of non-invasive cardiac monitoring on management. Arch Orthop Trauma Surg. 2007;127:121-123.
- Copetti R, Soldati G, Copetti P. Chest sonography: a useful tool to differentiate acute cardiogenic pulmonary edema from acute respiratory distress syndrome. Cardiovasc Ultrasound. 2008;6:16.
- Hurley ME, Keye GD, Hamilton S. Is ultrasound really helpful in the detection of rib fractures? Injury. 2004;35:562-566.
- Battistelli JM, Anselem B. Echography in injuries of costal cartilages. J Radiol. 1993;74:409-412.
- Bitschnau R, Gehmacher O, Kopf A, et al. Ultrasonography in the diagnosis of rib and sternal fracture. Ultraschall Med. 1997;18:158-161.
- Griffith JF, Rainer TH, Ching AS, et al. Sonography compared with radiography in revealing acute rib fracture. AJR Am J Roentgenol. 1999;173:1603-1609.
- Kara M, Dikmen E, Erdal HH, et al. Disclosure of unnoticed rib fractures with the use of ultrasonography in minor blunt chest trauma. Eur J Cardiothorac Surg. 2003;24:608-613.
- Turk F, Kurt AB, Saglam S. Evaluation by ultrasound of traumatic rib fractures missed by radiography. Emerg Radiol. 2010;17:473-477.
- Rainer TH, Griffith JF, Lam E, et al. Comparison of thoracic ultrasound, clinical acumen, and radiography in patients with minor chest injury. J Trauma. 2004;56:1211-1213.