Insufficiency fractures of the sternum: a consequence of thoracic kyphosis?

Sternal stress fracture presenting as acute chest pain

Sternal fractures are rare and are typically caused by major trauma such as motor vehicle collisions. However, sternal insufficiency fractures can occur with minimal to no trauma in patients with exaggerated thoracic kyphosis from multiple thoracic compression fractures, especially in the setting of osteoporosis. We describe a case of a sternal insufficiency fracture that presented as chest pain resembling a myocardial infarction. As sternal insufficiency fractures may vary in clinical presentation, this case demonstrates that radiologists should carefully evaluate the sternum, especially when risk factors are present. Furthermore, awareness and identification of these fractures can prevent unnecessary cardiac workups.

Uncommon cause of chest pain in a postoperative spinal patient

An 84-year-old woman with previous spinal operations including vertebroplasty and lumbar decompressions was admitted electively under the spinal team for right-sided L4/5 decompression for worsening back pain which she undergoes using a posterior approach. Postoperatively, she develops stabbing upper central chest pain and given unremarkable chest X-ray, ECG and cardiac troponin, she undergoes a CT pulmonary angiogram which shows a fracture of the upper part of sternum but no pulmonary embolism. There is no history of recent trauma and this is deemed to be secondary to prolonged spinal surgery in the prone position in a patient with osteopenic bones. To date, we have not come across a case of spontaneous sternal fracture as a complication of spinal surgery at our regional spinal unit. Most cases of sternal fractures are secondary to blunt anterior chest wall trauma with spontaneous fractures and stress fractures being rare.

OCCULT MANUBRIOSTERNAL JOINT INJURY ASSOCIATED WITH FRACTURE OF THE THORACIC SPINE

The authors report the occurrence of an occult manubriosternal joint injury in the initial evaluation on a patient with a thoracic spine fracture (T9). This T9 fracture was diagnosed in a 37-year-old man and was associated with a partial neurological deficit. At the initial evaluation, the radiographs produced did not show the manubriosternal joint injury. During rehabilitation, after surgical stabilization of the thoracic spine fracture, the patient suddenly felt an intense pain accompanied by deformation at the sternal level. From imaging examinations, manubriosternal luxation was diagnosed. Because of recurrence of the luxation and the incapacitating pain, open reduction and fixation of the manubriosternal joint had to be performed. At the 12-month follow-up, the patient presented complete recovery of the neurological lesion, consolidation of the arthrodesis on the T7-T11 vertebral segment and maintenance of the reduction of the manubriosternal joint, which was asymptomatic during daily activities.

Atraumatic sternum fracture

The spine, pelvic bones and long bones of the lower extremities are common sites for insufficiency fractures. Cases of sternum insufficiency fractures have rarely been reported among elderly patients. Insufficiency fractures tend to occur in bones with decreased mechanical strength especially among elderly patients, in postmenopausal women and patients with underlying diseases. We describe a case of spontaneous sternum insufficiency fracture in a healthy man, with no known risk factors to fracture, or previous history of fractures. Sternum insufficiency fracture is a rare cause of chest pain. This case serves to remind the emergency physician to remain vigilant for other non-cardiac, non-pulmonary and non-traumatic causes of chest pain, especially among patients with known risk factors such as osteoporosis, chronic obstructive pulmonary disease, rheumatoid arthritis, systemic lupus erythematosus and patients on long-term steroid treatment. If diagnosed correctly, these patients can be discharged and treated as outpatients as this case emphasises.

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.

Multidetector CT scan in the evaluation of chest pain of nontraumatic musculoskeletal origin

Acute nontraumatic chest pain is a common presenting symptom to the emergency department. Often, it is evaluated by MDCT with PE, aortic dissection, or coronary artery protocols. The parameters used for these MDCT protocols are very similar to those used in protocols for dedicated imaging of the musculoskeletal system. Thus, these studies are not only effective in evaluating for these traditional vascular causes of chest pain, but also in evaluating musculoskeletal causes of chest pain, including those of infectious, rheumatologic, and systemic causes. In essence, every MDCT of the chest is also a musculoskeletal examination of the chest and anyone interpreting these images must be familiar with the MDCT-imaging appearance of common musculoskeletal causes of acute nontraumatic chest pain.

Sternal fractures

Sternal fractures are relatively common and range from simple unicortical cracks to displaced fractures associated with life threatening injuries. This paper describes the relevant anatomy, biomechanics, mechanism of injury, clinical presentation, investigation, treatment and complications and also includes associated and concomitant injuries. A management flow chart including criteria for discharge from the emergency department is presented.

Sternum insufficiency fracture presenting as acute chest pain: a case report and review of the literature

The spine, pelvic bones and long bones of the lower extremities are common sites for insufficiency fractures. Cases of sternum insufficiency fractures have been rarely reported in an elderly patient. Insufficiency fracture tends to occur in bones with decreased mechanical strength. It tends to occur in elderly patients, especially in postmenopausal women, with underlying diseases. We describe a case of sternum insufficiency fracture in a patient with rheumatoid arthritis and systemic lupus erythematosus on long-term corticosteroid therapy diagnosed in an emergency setting. Sternum insufficiency fracture is a rare cause of chest pain. This case serves to remind the emergency physician to remain vigilant for other noncardiac and nontraumatic causes of chest pain. If diagnosed accurately, these patients can be discharged and treated as outpatients.

Traumatic manubriosternal dislocation

Manubriosternal dislocation is an extremely rare occurrence, especially as the result of an indirect compression injury. Manubriosternal dislocations are divided into two types: In a Type I dislocation, the body of the sternum is displaced in a dorsal direction; in Type II dislocation, the body is displaced to the ventral side of the manubrium. A manubriosternal dislocation may be caused by direct or indirect trauma. Direct injury is generally a collision injury occurring in the context of a road accident. Resulting may be in either a Type I or Type II dislocation. Indirect trauma always leads to a Type II dislocation due to a flexion-compression mechanism in the region of the spine. Rheumatic arthritis and obvious kyphosis are predisposing factors in manubriosternal dislocation due to the indirect compression injury. Non-operative treatments after reduction, e.g. correction tape or plaster bandage, symptomatic pain treatment, application of ice, and several weeks without sports, are associated with a not inconsiderable rate of subluxations or reluxations, especially due to insufficient patient compliance. These disorders can lead to chronic pain, periarticular calcification with ankylosis, and progressive deformity. It has not been possible to establish an optimal, standardized operative procedure so far because of the small number of cases. We have achieved very good, postoperative long-term outcomes after plate osteosynthesis of manubriosternal dislocations in two patients.

Pulmonary Rehabilitation for Restrictive Lung Impairment Secondary to Osteoporotic Sternal Fracture: A Case Report

We report a case of a spontaneous sternal fracture secondary to idiopathic osteoporosis in a man in his late forties. His restrictive lung disorder from thoracic kyphoscoliosis was exacerbated by surgery to repair the sternal fracture. Inpatient cardiopulmonary rehabilitation helped this patient regain independence in functional status and ambulation after repair of the fractured sternum.

Insufficiency fractures of the sternum

Insufficiency fractures occur within weakened bones that are unable to withstand the stress of every day normal activities. The spine, pelvis, and lower long-bone extremities are common sites of insufficiency fractures. Spontaneous sternal insufficiency fracture (SIF) has rarely been reported in elderly patients. To recognise a sternal insufficiency fracture is important in selecting the adequate diagnostic procedures.

Association of posterior rib fractures with exaggerated kyphosis and sternal collapse

The ribs, sternum, and vertebrae all play an important role in stabilizing the thorax. Failure of one of these components places additional stress on the other supporting structures. We present a case of a 62-year-old man with multiple myeloma and osteopenia who sustained fractures to all three components.

A case of sternal insufficiency fracture

We report a case of insufficiency fracture of the sternum in a 70-year-old female patient with a review of the literature. She complained of sudden onset chest pain and aggravating dyspnea. She has been managed with corticosteroid due to chronic obstructive pulmonary disease for 15 years. Diagnosis of sternal insufficiency fracture presented with thoracic kyphosis was made on the basis of absence of trauma history, radiologic findings of lateral chest radiograph, bone scintigraphy and chest computed tomography. Thoracic kyphosis and osteoporosis secondary to menopause, corticosteroid therapy and limited mobility due to chronic obstructive pulmonary disease were considered as predisposing factors of the sternal insufficiency fracture in this patient.

Stress fracture of the sternum: an unusual injury?

Stress fracture of the sternum is a rare condition which presents as acute anterior chest pain after repetitive upper-body exercise. Two case reports are presented and it is postulated that this is an often underdiagnosed condition which should be considered in the differential diagnosis of acute chest pain in the athlete. Awareness of the injury together with meticulous clinical examination supported by good quality radiographs or isotope bone scan may lead to an increase in the diagnosis of this injury.

Spontaneous fracture of the sternum simulating myocardial infarction

Spontaneous fractures of the sternum are rare but worth knowing as they may simulate acute cardiac and pulmonary emergencies. A case of an insufficiency sternal fracture mimicking myocardial infarction and subsequent anginal pain is presented. The risk factors of this condition, its clinical features and the diagnostic procedures are discussed. Spontaneous fractures of the sternum should be considered as a diagnostic possibility for unexplained chest pains in the elderly.

Insufficiency stress fractures

Bones weakened by osteopenia have insufficient elastic resistance to withstand even the minimal mechanical stresses of normal daily activity. Repetitive subthreshold injury to these susceptible bones results in insufficiency-type stress fractures. The spine, pelvis, and lower extremities are commonly affected by these fractures. Insufficiency fractures create a diagnostic challenge for clinicians and radiologists alike. The radiographic evidence of the fracture is often so subtle that it escapes detection. Conversely, findings on other studies may be so striking that they suggest metastatic disease. Insufficiency fractures are often subjected to unnecessary biopsies, and they have been treated unwittingly with chemotherapy and radiation therapy. Radiologists are in a key position to prevent these errors. A thorough familiarity with the characteristic appearance and location of these fractures assures the correct diagnosis.

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.

Atraumatic sternal fractures secondary to osteoporosis

We describe two cases of spontaneous sternal fracture with no underlying pathology other than a severe dorsal kyphosis resulting from osteoporosis. Both patients complained of chest pain. Sternal fractures are particularly likely to occur in the elderly when the costal cartilages become ossified and there is an associated thoracic kyphosis. In elderly patients with a kyphosis the lateral thoracic radiograph should include the sternum to ensure recognition of this complication.