Sternal fractures--the natural history

Statistical analysis of biomechanical properties and size of the sternum and its fracture risk in a Japanese sample

OBJECTIVE

Sternal fractures can have life-threatening complications. To understand chest injury mechanisms, sufficient data regarding the mechanical properties and structure of the sternum are required. The aim of this study was to examine the mechanical properties and size of the sternum in a Japanese forensic sample.

MATERIALS AND METHODS

Sterna were obtained from 120 Japanese dead bodies of known age and sex. The sample thickness (ST) and the sample width (SW) were measured using a computed tomographic image. Three-point-bending tests were conducted using a three-point-bending apparatus to assess the fracture load (FL) of the sample. Then, the flexural strength (FS) was calculated and the natural logarithm of FL (ln FL) and FS (ln FS) were also calculated.

RESULTS

The values of ST, ln FL, and ln FS for male samples were significantly greater than those for female samples. Both ln FL and ln FS had significant negative correlations with age regardless of sex; the Pearson product-moment correlation coefficients were larger for female samples than for male samples. Although age was significantly negatively correlated with SW in female samples, there was no significant correlation between age and SW in male samples. No significant correlations were found between age and ST regardless of sex.

CONCLUSION

This is the first study to present quantitative data on the biomechanical properties of the sternum. Because of the smaller sternal strength of elderly women, it is especially important for them to avoid the risk of sternal fractures.

Sternal fractures in children: An analysis of the National Trauma Data Bank

PURPOSE

The purpose of this study was to describe the epidemiology and evaluate the clinical significance of traumatic sternal fractures.

METHODS

Patients age ≤18 years with sternal fractures in the National Trauma Database research datasets from 2007-2014 were identified. Patient demographics, injuries, procedures, and outcomes were analyzed using descriptive statistics and logistic regression.

RESULTS

Three thousand one hundred sixty patients with sternal fracture were identified. Ninety percent of injuries occurred in patients between 12 and 18 years old. Median injury severity score (ISS) was 17 [9,29]. Exploratory thoracotomy was performed in 1%. Thirty-nine percent were admitted to the intensive care unit (ICU). On multivariate regression, predictors of ICU stay >1 day were increasing ISS, lack of the use of protective devices, decreasing Glasgow Coma Score (GCS), tachycardia, and pulmonary contusion. Median hospital length of stay was 4 [2, 9] days. In-hospital mortality was 8%. Predictors of mortality were lower GCS, increasing ISS, decreasing oxygen saturation, hypotension, and cardiac arrest. Use of protective devices and seat belts did not affect mortality.

CONCLUSION

Sternal fractures in patients increase in incidence with age, and poor outcomes are impacted by associated injuries and complications. The presence of a sternal fracture should trigger a careful diagnostic evaluation.

LEVEL OF EVIDENCE

III STUDY TYPE: Treatment Study.

Traumatic sternal injury in patients with rib fracture: A single-center experience

Purpose:

We aimed to assess the pattern and impact of sternal injury with rib fracture in a Level 1 trauma center.

Patients and Methods:

We conducted a retrospective review of trauma registry data to identify patients who presented with sternal fracture between 2010 and 2017. Data were analyzed and compared in patients with and without rib fracture.

Results:

We identified 212 patients with traumatic sternal injury, of them 119 (56%) had associated rib fractures. In comparison to those who had no rib fracture, patients with rib fractures were older (40.1 ± 13.6 vs. 37.8 ± 14.5), were frequently involved in traffic accidents (75% vs. 71%), had higher chest abbreviated injury scale (AIS 2.8 ± 0.6 vs. 2.2 ± 0.5) and Injury Severity Score ( ISS 17.5 ± 8.6 vs. 13.3 ± 9.6), were more likely to be intubated (33% vs. 19%), required chest tube insertion (13.4% vs. 4.3%), and received blood transfusion (29% vs. 17%). Rates of spine fracture, head injury, and solid organ injury were comparable in the two groups. Manubrium, clavicular and scapular fractures, lung contusion, hemothorax, and pneumothorax were significantly more evident in those who had rib fractures. Hospital length of stay was prolonged in patients with rib fractures (P = 0.008). The overall mortality was higher but not statistically significant in patients with rib fractures (5.0% vs. 3.2%).

Conclusions:

Sternal fractures are rare, and detection of associated injuries requires a high index of suspicion. Combined sternal and rib fractures are more evident in relatively older patients after chest trauma. This combination has certain clinical implications that necessitate further prospective studies.

Imaging and Management of Thoracic Trauma

Thoracic injury results from penetrating and blunt trauma and is a major contributor to overall trauma morbidity and mortality in the United States. Modern imaging algorithms utilize ultrasound, chest radiograph, and computed tomography with intravenous contrast to accurately diagnose and effectively treat patients with acute thoracic trauma. This review focuses on the etiologies, signs and symptoms, imaging, and management of several life-threatening thoracic injuries including tracheobronchial rupture, pulmonary parenchymal injury, hemothorax, pneumothorax, diaphragmatic rupture, and axial skeleton injury.

Right Ventricular Epicardial Fibrosis in Mice With Sternal Segment Dislocation

We report coincident sternal segment dislocation and focally extensive right ventricular epicardial fibrosis observed during routine histopathology evaluation of C57BL/6N mice as part of a high throughput phenotyping screen conducted between 4 and 16 weeks of age. This retrospective case series study was conducted to determine whether cardiac fibrosis was a pathological consequence of sternal segment dislocation. We identified sternal segment dislocation in 51 of the total 1103 mice (4.6%) analyzed at 16 weeks of age. Males were more frequently affected. In all cases but 2, the dislocation occurred at the fourth intersternebral joint. In 42 of the 51 cases (82.4%), the dislocation was encased by regenerative cartilaginous callus that protruded internally into the thoracic cavity (intrathoracic callus) and/or externally to the outer aspect of the sternum (extrathoracic callus). Displacement of dislocated ends of the sternum into the thoracic cavity was present in 19 of 51 cases (36.5%). Coincident minimal or mild right ventricular epicardial and subepicardial fibrosis was observed in 22 of the 51 cases (43%) but was not observed in any of the mice in the absence of sternal segment dislocation. Our data suggest that right ventricular fibrosis was likely caused by direct injury of the right ventricle by the dislocated ends of the sternum and/or by intrathoracic callus that develops post dislocation. Potential pathogenesis for the sternal and cardiac lesions and their implication for the interpretation of phenotypes in mouse models of cardiopulmonary and skeletal disease are discussed.

Sternal fracture--an analysis of the National Trauma Data Bank

BACKGROUND

The clinical significance of sternal fractures (SFs) after blunt trauma is heavily debated. We aimed to test the hypothesis that isolated SF is not associated with significant morbidity or mortality.

MATERIALS AND METHODS

The National Trauma Data Bank (NTDB) sets for 2007-2010 were retrospectively examined. Adult subjects with SF were identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnostic codes. Data collected included demographics, mechanisms of injury, clinical variables, and in-hospital mortality. The primary outcome measure was in-hospital mortality. Secondary outcome measures included hospital length of stay, intensive care unit days, and ventilator days.

RESULTS

A total of 32,746 subjects with SF were included. Motor vehicle crash (MVC) was the most common mechanism (84%) in this group and SF was present in 3.7% of all patients admitted after MVC. The mean age was 51 y, 66% were males, and most were white (74%). Overall in-hospital mortality was 8.8% and mortality with isolated SF was 3.5%. Increasing thoracic fracture burden (rib fracture, clavicular fracture, and scapular fracture) was associated with increasing hospital length of stay, intensive care unit days, ventilator days, and mortality. On multivariate regression analysis, other significant predictors of mortality were cardiac arrest, acute respiratory distress syndrome, pulmonary embolism, blunt cardiac injury, pulmonary contusion, increasing age, and lack of insurance.

CONCLUSIONS

SFs occur in 3.7% of victims after MVC. With isolated SF, the mortality rate is low (3.5%); the tendency for poorer outcomes is most heavily influenced by associated injuries (pulmonary contusions, other thoracic fractures), complications (cardiac arrest, pulmonary embolism, acute respiratory distress syndrome), comorbidities (currently on or requiring dialysis, residual neurologic deficit from stroke), and lack of insurance.

Current management of isolated sternal fractures in the UK: time for evidence based practice? A cross-sectional survey and review of literature

Routine admission of patients with isolated sternal fractures for observation is still widespread in the UK. However, the evidence appears to suggest that this is unnecessary. We undertook a cross-sectional telephone survey of management of isolated sternal fractures in the UK. We contacted 85 acute admitting units over a three-month period and were able to get a response from 67 units. Most of the hospitals were district general hospitals (52) and situated in England (49). The orthopaedic department was the most common admitting department. 51 units indicated that they regularly admit isolated sternal fractures for observation. Other indications for admission included pain control (33), abnormal cardiac enzymes (28), social circumstances (23), abnormal electrocardiogram (6), and low oxygen saturation (5). Chest X-ray was performed on admission in all hospitals. 57 hospitals performed ECG and cardiac enzyme tests prior to admission and 6 hospitals carried out echocardiogram following admission on a regular basis. Patients were not followed up on discharge. 2 hospitals with on-site cardiothoracic unit followed-up patients on discharge, and 1 hospital advised GP follow-up. A review of the literature indicated that patients with isolated sternal fractures are at low risk of significant cardiac, pulmonary or mediastinal complications and do not need extensive investigations or routine admission. The current practice of management of isolated sternal fractures in the UK does not appear to conform to available evidence. In order to decide on management plans based on more rigorous evidence, there is a need for a prospective double blind randomised study of patients with isolated sternal fractures, comparing those discharged to those admitted over a longer follow-up period.

Transpedicular partial corpectomy without anterior vertebral reconstruction in thoracic spinal metastases

STUDY DESIGN

We retrospectively reviewed surgical results of posterolateral transpedicular partial corpectomy without anterior vertebral reconstruction in 23 consecutive patients with symptomatic metastatic spinal cord compression at thoracic spine.

OBJECTIVE

To evaluate postoperative outcomes and survival rates of patients undergoing transpedicular partial corpectomy without anterior vertebral reconstruction.

SUMMARY OF BACKGROUND DATA

The need for anterior reconstruction after radical resection of vertebral body tumors has been emphasized by several authors. However, the stability of thoracic spine is substantially increased by the rib cage. The role of reconstruction may be not necessary in thoracic spine when partial corpectomy is performed.

METHODS

From November 2001 to November 2006, 23 patients with symptomatic metastatic spinal cord compression at thoracic spine underwent palliative surgery using a transpedicular partial corpectomy without anterior vertebral reconstruction. The indication for surgery was neurologic progression due to spinal cord compression.

RESULTS

Patients ranged in age from 20 to 88 years (mean, 57.0 years). Neurologic improvement by at least one Frankel grade was noted in 19 of 23 cases (82.6%). Overall, 73.9% of patients (17 of 23) could walk after surgery. There was no intraoperative mortality. Median survival time was 11.3 months. There was no implant failure.

CONCLUSION

The results of this study suggest that the stability of implants can be maintained up to 55.8 months without anterior vertebral reconstruction in thoracic spine.

Stability provided by the sternum and rib cage in the thoracic spine

STUDY DESIGN

Multidirectional flexibility tests were conducted on 10 human thoracic spines with intact rib cage.

OBJECTIVES

To determine the amount of stability the rib cage imparts to the thoracic spine and to show the amount of stability lost by a sternal fracture.

SUMMARY OF BACKGROUND DATA

There is no published study of biomechanical testing of human cadaveric specimens with the rib cage intact.

METHODS

In this study, 10 human cadaveric thoracic spines with the rib cage intact were tested using a biaxial material testing machine and an opto-electronic three-dimensional motion measuring device (Opto-trak 3020). The specimens were tested in axial compression, axial rotation, lateral bending, and flexion/extension. First, the specimens were tested through all four loading types with the sternum and rib cage intact. Next, the sternum was fractured at the sternomanubrial junction displacing the proximal fragment posteriorly. Lastly, the entire rib cage was removed.

RESULTS

The rib cage increased the stability of the thoracic spine by 40% in flexion/extension (P = 0.012), 35% in lateral bending (P = 0.008), and 31% in axial rotation (P = 0.008). An indirect flexion-compression type of sternal fracture decreased the stability of the thoracic spine by 42% in flexion/extension (P = 0.036), 22% in lateral bending (P = 0.038), and 15% in axial rotation (P = 0.011).

CONCLUSION

The rib cage significantly increases the stability of the thoracic spine in flexion/extension, lateral bending, and axial rotation. A sternal fracture significantly decreases the stability of the thorax.

The Sternal Fracture: Radiographic Analysis of 200 Fractures with Special Reference to Concomitant Injuries

BACKGROUND

The assessment of the sternal fracture and concomitant injuries is discussed.

METHODS

Two hundred sternal fractures were analyzed with respect to accident circumstances, fracture morphology and topography, and associated injuries.

RESULTS

Traffic accidents were frequent; 89.2% of them were motor vehicle crashes of restrained passengers, 76.5% of fractures were localized in the corpus sterni, and 8.5% of the injuries resulted in fractures or complete disruptions of the synchondrosis manubriosternalis. Nondisplaced or slightly displaced fractures (75.5%) occurred more frequently compared with moderately and severely displaced fractures (24.5%). In 29.5% of the patients, concomitant thoracic injuries were diagnosed. Spinal fractures were evaluated in 13%. In displaced fractures of the corpus, thoracic and cardiac injuries were observed frequently. In fractures or disruptions of the synchondrosis manubriosternalis, concurrence of spinal fractures clearly increased.

CONCLUSION

The observation of fracture morphology and topography, with reference to displacement, gives important information about the existence of serious concomitant injuries and can determine further diagnostic and therapeutic options in sternal fractures.

Traumatic sternal fracture: outcome following admission to a Thoracic Surgical Unit

INTRODUCTION

We reviewed our experience of the in-hospital management and early follow-up of patients admitted with a traumatic sternal fracture to a Thoracic Surgical Unit.

PATIENTS AND METHODS

Over a 7-year period, 73 consecutive patients (51 males) with a median age of 51 (range 17-84) years were admitted through the Emergency Department with an acute traumatic sternal fracture. The patients were hospitalised for cardiorespiratory monitoring, pain control and physiotherapy. Outpatient follow-up occurred 6 weeks after discharge.

RESULTS

The median hospital stay was 2 days (range 1-15 days). Sixty-four patients (88%) did not require parenteral analgesia or any other procedure that would necessitate admission to hospital. Three patients (4%) with severely displaced fractures and complex co-morbidities required surgical correction. Follow-up revealed no significant complications.

CONCLUSIONS

Admission to hospital is not necessary for every patient sustaining a sternal fracture and should be reserved for those with high-impact trauma, severely displaced fractures, significant associated injuries, complex analgesic requirements, important co-morbidities or inadequate domestic support.

Apophyseal dislocation of the body of the sternum in a child: a case report

A 4-year-old boy received a blow to the chest and sustained an apophyseal dislocation of the body of the sternum. The dislocation was treated by open reduction and internal fixation. This type of injury is so rare that no studies could be found.

Decelerational thoracic injury

BACKGROUND

Among the five major decelerational thoracic injuries [myocardial contusion (MC), traumatic aortic disruption (TAD), sternal fracture (SF), flail chest (FC), and tracheobronchial disruption (TBD)], coexisting injuries are seemingly rare.

METHODS

To test this hypothesis, we reviewed the records of all patients, with final diagnosis (FDX) codes of these injuries, treated at our Level I trauma center for the 10 years preceding 1997.

RESULTS

Among 142 patients, all victims of motor vehicle crashes, there were 38 MC, 36 TAD, 33 FC, 28 SF, and 7 TBD. There were six coexisting injuries (3.5%). Three patients with coexisting injury died in the operating room. All three had TAD; one of these three had TBD plus MC; one had additionally FC and MC and the third had FC in addition to the TAD. One patient with SF and probable MC died in the emergency room. Two patients with FC and a coexisting injury survived. One had MC, the other SF.

CONCLUSION

We conclude that these decelerational thoracic injuries, with the exception of sternal fracture, are sufficiently life threatening by themselves to cause fatality. When combined, the threat to life is potentiated. Death occurs at the scene or shortly after arrival in the ER. The diagnosis of one may help exclude the diagnosis of each of the other four. The role of sternal fracture in this paradigm remains an enigma.

Imaging in thoracic trauma: the trauma surgeon's perspective

Thoracic trauma is a common cause of significant disability and mortality. Most thoracic injury in developed countries results from motor vehicle crashes (MVC). Imaging of patients with thoracic trauma must be accurate and timely to avoid preventable death. Trauma surgeons prioritize imaging options based on the patient's hemodynamic status, associated injuries, and age. The screening test for the detection of life-threatening thoracic injury is the supine anteroposterior (AP) chest radiograph. Rib fractures are a marker for serious associated injuries, including abdominal injuries. Rib fractures are especially ominous in children and the elderly. Thoracic aortic injury is associated with high-speed mechanisms of injury and can occur in the absence of radiographic signs. Chest computed tomography (CT) can be used as a screening and diagnostic tool for suspected aortic injury. Aortography is reserved for patients with high suspicion of aortic injury or for confirmation of CT scan diagnosis.

Anterior mediastinal abscess after closed sternal fracture

BACKGROUND

Although sternal fractures after blunt chest trauma are markers for significant impact, the fracture itself is generally not associated with any specific wound complications. Mediastinal abscess and sternal osteomyelitis rarely occur after blunt trauma or cardiopulmonary resuscitation. Management of such complications is difficult, and requires a spectrum of operative procedures that range from simple closure to muscle flap reconstruction.

METHODS

The trauma registry of a Level I trauma center was used to identify patients suffering a sternal fracture between January of 1994 and August of 1997. Records were reviewed for the mechanism of injury, length of hospital stay, and posttraumatic mediastinal abscess.

RESULTS

Twenty-six patients were identified with sternal fracture. No clinically significant cardiac or aortic complications were noted. Three patients, all with a history of intravenous drug abuse and requiring central venous access in the emergency room, developed methicillin resistant Staphylococcus aureus mediastinitis. Sternal re-wiring and placement of an irrigation system successfully treated all three patients.

CONCLUSION

Posttraumatic mediastinal abscess is an uncommon complication of blunt trauma in general and sternal fracture in particular. It can be recognized by the development of sternal instability. Risk factors include the presence of hematoma, intravenous drug abuse, and source of staphylococcal infection. Treatment with early debridement and irrigation can avoid the need for muscle flap closure.

CT findings of sternal fracture

A retrospective study of blunt chest injuries due to motor vehicle accidents between the years 1990 and 1995 found 9 cases of sternal fracture that had both lateral plain film and thoracic axial CT scans performed. Plain film identified 8 of the 9 fractured sternums. CT scanning was only able to identify 6 sternal fractures. Secondary signs of sternal fracture were only seen in 5 of 9 patients, 3 had retrosternal haematomas and 2 had haematoma of the mediastinum.

CONCLUSIONS

(1) plain film is still superior to Axial CT scanning for identification of sternal fracture; (2) retrosternal haematoma, although a specific sign for sternal fracture has low sensitivity (3/9); (3) mediastinal haematoma, a poorly specific sign for sternal fracture also demonstrated low sensitivity.

Long-term morbidity in patients suffering a sternal fracture following discharge from the A and E department

OBJECTIVE

To describe the duration of symptoms and long term outcome in patients who were discharged home from the A and E department having sustained an isolated fracture of the sternum.

DESIGN

Postal questionnaire.

OUTCOME MEASURES

Patients were asked specific questions regarding advice and analgesia given on discharge, length of time off work, if appropriate, and length of time of symptoms related to the injury.

RESULTS

A response rate of 55% was achieved. The majority of patients had been involved in a motor vehicle accident. Chest pain was the predominant persisting symptom lasting for a mean period of 10.9 weeks. Duration of symptoms was significantly prolonged in patients over the age of 50 (p < 0.03). Although injury was more common in females this was not statistically significant (p < 0.09). Advice given regarding rehabilitation was poor and variable.

CONCLUSION

Patients suffering a sternal fracture have prolonged symptoms. Those being discharged home from the A and E department are at present being given variable and poor advice. A more formal approach to rehabilitation, analgesia and a letter to the general practitioner outlining prognosis will improve their standard of care.

Sternal fractures in blunt chest trauma: a practical algorithm for management

A retrospective review of the medical records of blunt trauma patients with sternal fracture admitted to a level 1 trauma center from June 1990 to June 1993 was undertaken to determine the relationship between sternal fractures and clinically significant myocardial injury, and to assess the usefulness of cardiac evaluation and monitoring in these patients. Of 33 patients with sternal fracture, 31 were in motor vehicle crashes and 2 were pedestrians struck. All had Glasgow Coma Scale score = 15. No patient had a severe, life-threatening, associated injury (Abbreviated Injury Score of >3). No electrocardiogram or echocardiogram showed evidence of acute injury or ischemia. No arrhythmias requiring treatment were noted. No CPK-MB fraction was >5%. These results show that sternal fracture is not a marker for clinically significant myocardial injury. The management of sternal fracture patients should be directed toward the treatment of associated injuries.

Sternal fracture - regional experience

A retrospective analysis of 27 sternal fracture patients out of 267 patients with chest trauma was done in the period between March 1990 (9-1410) and April 1994 (11-1414) at Asir Central Hospital, giving an incidence of 10% in all chest trauma. There were 25 males and two females, giving a ratio of 12.5:1. The age range was 18-70, with a mean age of 37.5 years and a median age of 35 years. The mean hospital stay was 12.2 days, with a range of 3 to 53 days and a median of seven days. The mechanism of injury and the types of associated injuries are presented. Twenty-eight percent of the sternal fracture patients had abnormal electrocardiogram. Echocardiogram was done on only eight patients (32%); two were abnormal.

Case report: sternal fracture from a seatbelt

We report a case of a sternal fracture in a patient restrained by a seatbelt on the passenger side of a car in a moderate-speed motor vehicle accident. This patient apparently did not have contact with any fixed part of the car. In reporting this case it is our intention to demonstrate that the increased use of seatbelts, although life-saving in many ways, may be associated with emergence of a new spectrum of less "life-threatening" injuries associated with their use. We, therefore, make a case for increased search for sternal injuries and potential complications (including cardiac) for restrained passengers without evidence of other direct chest trauma. We believe that although seatbelts are an essential part of passenger car safety, their use should not deter extensive investigation when evaluating the emergency patient for injuries usually associated with the unrestrained passenger.

Spontaneous sternal fractures in four patients with chronic airflow obstruction taking corticosteroids

Four patients with chronic airflow obstruction developed spontaneous sternal fractures. All had received repeated courses of high dose corticosteroids and three were receiving long term treatment with low dose corticosteroids. It is important to consider sternal fracture in the differential diagnosis when patients with chronic airflow obstruction present with chest pain.

Myth of the dangerous sternal fracture

STUDY OBJECTIVE

To look at the hospital course and the outcome of patients with an isolated sternal fracture.

DESIGN

Retrospective analysis of hospital records.

SETTING

A large urban Level I trauma center.

TYPE OF PARTICIPANT

Blunt trauma patients with an isolated sternal fracture. Patients with other chest radiograph abnormalities were excluded, as were those with abnormal admission ECGs.

MEASUREMENTS AND MAIN RESULTS

Thirty-one patients with an isolated sternal fracture were identified. No patient developed new ECG changes or arrhythmias during the hospital stay. Cardiac enzymes were elevated in one patient (3.2%). No patient had any adverse cardiopulmonary outcome attributable to the sternal fracture.

CONCLUSION

The outcome of patients with an isolated sternal fracture and a normal ECG is very good. Routine admission and cardiac monitoring do not appear to be warranted in this subset of patients with a sternal fracture.

Sternal fracture: what investigations are indicated?

A retrospective study of 55 patients with sternal fractures is presented in an attempt to determine which investigations are predictive of complications. We conclude that isolated sternal fractures, in the absence of clinical evidence of cardiac or respiratory complications, and with a normal electrocardiogram and postero-anterior chest radiograph, require no further investigation.

Does sternal fracture increase the risk for aortic rupture?

We retrospectively reviewed the records of 99 patients who suffered sternal fractures between 1968 and 1987. Patients ranged in age from 5 to 86 years. The most common cause of injury was a motor vehicle accident. The 99 patients were compared with a concurrent series of 2,106 patients with chest injuries and no sternal fractures. Traumatic aortic rupture occurred in 2 of 99 patients with sternal fractures (2%) and in 75 of 2,106 patients without sternal fracture (3.6%). This difference was not statistically significant by the Fisher exact test (p = 0.326). We conclude that traumatic aortic rupture does not occur more commonly in patients with sternal fracture when compared with other patients with blunt chest injuries.