Both PSF and ISF commonly result from blunt chest trauma sustained in motor vehicle accidents or falls [1]. Less frequently, patients present with SF after other forms of accidents or assault. About 75% of those cases correspond to PSF, only 25% to ISF. Besides blunt trauma, distinct pathologies may lead to SF. In detail, osteoporosis and severe thoracic kyphosis predispose for this lesion [3]. Postmenopausal women, elder patients as well as those receiving long-term corticosteroid therapy are at particularly high risks [4]. In this context, ISF is much more common than PSF.

Midline chest pain is the single most important symptom of any SF. It may be the only symptom, especially in ISF patients [4]. SF may be accompanied by retrosternal or mediastinal hematoma, and affected individuals may experience symptoms of blood loss and hemodynamic instability. Hematomas may also compress vital structures in the thoracic cavity, thereby interfering with heart and lung function [5].

Few SF are palpable.

PSF patients may additionally suffer from symptoms associated with:

• Rib fractures
• Flail chest
• Pulmonary contusion
• Pneumothorax
• Blunt cardiac injury
• Aortic rupture and other vascular injuries
• Hemothorax
• Ruptured diaphragm

• Intravenous Drugs

  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. [ncbi.nlm.nih.gov]

  Risk factors include the presence of a large hematoma, intravenous drug abuse, and another source of a staphylococcal infection. Treatment is open debridement. Schulz-Drost S, Krinner S, Langenbach A, Oppel P, Lefering R, Taylor D, et al. [emedicine.medscape.com]

• Chest Wall Pain

  During workup, the patient complained of midline chest pain, and left chest wall pain. [westjem.com]

• Painful Cough

  The patient will feel tenderness at the front of the chest over the bone and breathing may be painful. Coughing and sneezing are also likely to reproduce pain and bruising may appear later. [sportsinjuryclinic.net]

• Chest Pain

  Acute surgical therapy is indicated for debilitating chest pain usually associated with fracture displacement. We report a case of debilitating chest pain associated with a chronic sternal fracture. [ncbi.nlm.nih.gov]

  […] completely ossify before age 18, physeal injury must be suspected with chest pain in a young athlete. [healio.com]

  Her chest pain and dyspnea were declined by the administration of calcitonin and analgesics. [kjim.org]

• Osteopenia

  Insufficiency fractures caused by abnormally decreased bone density or weakened bone can occur spontaneously in patients with osteoporosis or osteopenia (particularly in older persons, especially women), those on long-term steroid therapy, or those with [emedicine.com]

  Bones weakened by osteopenia have insufficient elastic resistance to withstand even the minimal stress of normal daily activity. [kjim.org]

• Sternal Tenderness

  Localized sternal tenderness was present in 68 (97.1%), external signs of contusion/ecchymosis in 33 (47.1%), and dyspnea in 10 (14.3%) patients. The mechanism of injury was motor vehicle crash in 64 (91.4%) patients, with 46 of these restrained. [ncbi.nlm.nih.gov]

  tenderness and pain who were discharged after normal lateral sternal radiography had such fractures. [emj.bmj.com]

• Sternal Tenderness

  Localized sternal tenderness was present in 68 (97.1%), external signs of contusion/ecchymosis in 33 (47.1%), and dyspnea in 10 (14.3%) patients. The mechanism of injury was motor vehicle crash in 64 (91.4%) patients, with 46 of these restrained. [ncbi.nlm.nih.gov]

  tenderness and pain who were discharged after normal lateral sternal radiography had such fractures. [emj.bmj.com]

Anamnestic data usually imply a patient to have sustained thoracic trauma. In such cases, extensive injuries may indicate the need to assure proper ventilation and cardiovascular function before taking diagnostic measures to assess the integrity of the sternum. Distinct imaging techniques may be applied to this end:

• Sonography has been shown to yield reliable results, is readily available and cost-effective [6].
• While anterior-posterior chest radiographs are of low sensitivity regarding the detection of SF, lateral sternal views often allow for the respective diagnosis [7]. Lucent fracture lines indicate the site of the lesion; displacement of bone fragments may be observed.
• Computed tomography may be required to depict SF that cannot be visualized by means of plain radiography and according to recent studies, this applies to the majority of minor SF [8]. However, computed tomography scans are associated with considerable exposure to ionizing radiation. Distinct algorithms have been developed to aid in the decision of whether blunt trauma evaluation should or should not comprise computed tomography scans [9] [10].

Additional studies are indicated to identify the underlying disease in patients presenting with pathological SF [3] [4] [11] [12].

• Non Specific ST-T Changes

  Electrocardiography (n 52) was abnormal in four patients--old myocardial infarction (n 1), non-specific ST-T changes (n 3). Cardiac enzymes (creatine-kinase-MB, n 42) were pathologically elevated in five patients. [ncbi.nlm.nih.gov]

• Abnormal ECG

  Abnormal ECG or cardiac enzymes with an isolated sternal fracture requires observation for possible blunt cardiac injury. [aliem.com]

  Abnormal ECG with normal troponin rules out BCI. Patients with abnormal ECG and troponin should be admitted with telemetry. Wiener Y 2001 Echocardiogram in sternal fracture. [east.org]

The sternum is commonly referred to as the breastbone and forms part of the thoracic wall. It is located in the center of the chest with its most cranial portion, the manubrium forming the sternoclavicular joints with the clavicles. Along the sternum's body, a total of fourteen sternocostal articulations connects the breastbone with seven true ribs on either side. Finally, the inferior portion of the sternum, the xiphoid process, constitutes the site of insertion of the costoxiphoid ligaments, tendons of the diaphragm, and determined abdominal muscles. Either part of the sternum may succumb to the impact of mechanical forces that exceed the maximal resistance of the breastbone, and the respective patient sustains a sternal fracture (SF).

As a whole, the rib cage provides mechanical protection to major blood vessels, mediastinal organs and vital thoracic organs like lungs and heart. Its physical integrity may be disrupted if a patient sustains thoracic trauma and due to the afore-described proximity of the sternum to other bones and organs, an individual suffering from SF commonly presents with additional fractures or lesions of internal organs. This condition may be referred to as polytrauma sternal fracture (PSF) and differs largely from the isolated sternal fracture (ISF) regarding clinical presentation, workup, and treatment [1].

In PSF patients, the outcome largely depends on the severity of accompanying injuries. ISF patients have an excellent prognosis and usually, recover within weeks [2].

1. Odell DD, Peleg K, Givon A, et al. Sternal fracture: isolated lesion versus polytrauma from associated extrasternal injuries--analysis of 1,867 cases. J Trauma Acute Care Surg. 2013;75(3):448-452.
2. de Oliveira M, Hassan TB, Sebewufu R, Finlay D, Quinton DN. Long-term morbidity in patients suffering a sternal fracture following discharge from the A and E department. Injury. 1998;29(8):609-612.
3. Horikawa A, Miyakoshi N, Kodama H, Shimada Y. Insufficiency fracture of the sternum simulating myocardial infarction: case report and review of the literature. Tohoku J Exp Med. 2007;211(1):89-93.
4. Wong JJ, Drew B, Stern P. Sternal insufficiency fracture related to steroid-induced osteoporosis: A case report. J Can Chiropr Assoc. 2013;57(1):42-48.
5. Crestanello JA, Samuels LE, Kaufman MS, Thomas MP, Talucci R. Sternal fracture with mediastinal hematoma: delayed cardiopulmonary sequelae. J Trauma. 1999;47(1):161-164.
6. Lahham S, Patane J, Lane N. Ultrasound of Sternal Fracture. West J Emerg Med. 2015;16(7):1057-1058.
7. Mavridis IN. Imaging techniques in the assessment of sternal fracture patients. Eur J Radiol. 2013;82(1):200.
8. Perez MR, Rodriguez RM, Baumann BM, et al. Sternal fracture in the age of pan-scan. Injury. 2015;46(7):1324-1327.
9. Brink M, Deunk J, Dekker HM, et al. Criteria for the selective use of chest computed tomography in blunt trauma patients. Eur Radiol. 2010;20(4):818-828.
10. Rodriguez RM, Anglin D, Langdorf MI, et al. NEXUS chest: validation of a decision instrument for selective chest imaging in blunt trauma. JAMA Surg. 2013;148(10):940-946.
11. Latzin P, Griese M, Hermanns V, Kammer B. Sternal fracture with fatal outcome in cystic fibrosis. Thorax. 2005;60(7):616.
12. Reuling EM, Jakma TS, Schnater JM, Westerweel PE. Spontaneous sternal fracture due to multiple myeloma requiring extensive surgical repair. BMJ Case Rep. 2015.