What every physician needs to know:
Common disorders of the chest wall may be broadly considered in three categories: chest wall trauma, chest wall masses, and scoliosis.
Chest Wall Trauma
Thoracic trauma includes injuries to the chest wall and the intrathoracic structures. Chest wall trauma is seen in 30 percent of patients who present with significant trauma; most of such cases are due to blunt thoracic trauma. Penetrating thoracic trauma is more likely to be associated with intrathoracic damage than is blunt chest wall trauma.
Flail chest is an unstable chest wall characterized by paradoxical movement of part of the chest during respiration. Flail chest is a clinical diagnosis that occurs in 10-15 percent of major chest trauma. The flail portion of the chest may entail multiple fractures in consecutive ribs, a single rib with multiple fractures, or costochondral separation. Mortality in flail chest may be as high as 50 percent and appears to be increased in the elderly. The likelihood of sustaining a concomitant, major intrathoracic injury is significantly increased in the setting of a flail chest.
Continue Reading
Open pneumothorax is a direct communication between the exterior environment and the pleural space. Injuries that allow air into the pleural space on inspiration and prevent egress of air on expiration create a flap-valve mechanism or sucking chest wound that may result in a tension pneumothorax, mediastinal shift, and rapid clinical decompensation.
Other chest wall trauma may include clavicular, sternal, and scapular fractures.
Trauma in children is a leading cause of death. A child’s chest is more compliant than an adult’s, so chest trauma in a child is more likely to lead to an intrathoracic injury. The most common cause of a rib fracture in a child is an inflicted injury; the finding should raise the question of an abusive situation, particularly in children under age three.
Chest Wall Masses
Chest wall masses, both benign and malignant, are relatively uncommon in clinical practice. The chest wall contains a number of distinct tissues, including skin, fat, muscle, bone, cartilage, lymphatics, blood vessels, and fascia. Each of these component tissues may be the substrate for a benign or malignant primary chest wall mass.
Scoliosis
Angulation of the spine may be anterior-posterior (kyphosis) or lateral (scoliosis) in orientation. Severe kyphoscoliosis produces significant rib distortion and respiratory dysfunction. Kyphoscoliosis is idiopathic in 80 percent and secondary in 20 percent of cases. The degree of respiratory impairment increases with age as the chest becomes progressively less compliant. Three percent of the population has scoliosis, but females are affected more than males in both prevalence and severity. Ten percent of adolescents with scoliosis require treatment.
Classification:
Chest Wall Trauma
Pneumothorax is air in the pleural space. Its development may collapse the lung, compress mediastinal structures, and obstruct venous return to the heart. A small pneumothorax is defined as collapse of less than a third of the lung, while a large pneumothorax involves complete unilateral lung collapse without mediastinal shift. Tension pneumothorax is defined as a completely collapsed lung with contralateral shift of mediastinal structures and decreased venous return to the heart.
Hemothorax is blood in the pleural space. The chest can hold as much as 3L of fluid or blood.
Fractures of the first and second ribs are more serious than lower rib fractures because of the implied additional traumatic force, which overcomes the protection offered by the scapula, clavicle, humerus, and their muscular attachments. Fractures of the lower ribs often damage abdominal organs like the liver or spleen.
Chest Wall Masses
Primary benign chest wall masses include infectious masses, soft-tissue neoplasms (lipoma, fibroma, hemangioma, granuloma, neurofibroma, elastoma, and desmoid tumors), bone and cartilage neoplasms (osteochondroma, chondroma, fibrous dysplasia, and eosinophilic granuloma, also known as Langerhan’s cell histiocytosis).
Primary malignant chest wall masses include soft-tissue malignant neoplasms (liposarcoma, leiomyosarcoma, rhabdomyosarcoma, malignant fibrous histiocytoma, and angiosarcoma) and bone and cartilage malignant neoplasms (solitary plasmacytoma, chondrosarcoma, osteosarcoma, and Ewing sarcoma).
Secondary masses of the chest wall include tumor invasion from contiguous organs and metastasis from distant organs.
Scoliosis
Idiopathic scoliosis is the most common type of scoliosis; however, neuromuscular disease, congenital vertebrae malformations, and other genetic syndromes may also produce clinically significant kyphoscoliosis.
Are you sure your patient has a chest wall disorder? What should you expect to find?
Chest Wall Trauma
Initial evaluation of the trauma patient begins with assessment of vital signs. In the setting of thoracic trauma, abnormal vital signs are more predictive of injury severity than is the mechanism of injury. The most common findings on physical examination in the setting of chest wall trauma include ecchymoses, lacerations, gross deformities or abrasions, abnormal breath sounds, pain on inspiration, and localized tenderness to palpation (suggesting a rib fracture).
Chest wall soft tissue emphysema most likely indicates damage to the lung parenchyma, airway, or esophagus. Intrapulmonary shunting, ventilation-perfusion mismatch, splinting, and hypoventilation as a result of poor pain control may lead to hypoxia. Dyspnea, tachypnea, engorged neck veins, unilateral hyperresonance to percussion, and absence of breath sounds and hypotension are associated with tension pneumothorax. In the setting of flail chest, abnormal or paradoxical chest wall movement, with or without muscle splinting, may be seen. Signs of more complicated and serious traumatic thoracic injury include muffled heart sounds and cardiac ectopy.
Chest Wall Masses
A careful history of any symptoms associated with diagnosis of a chest wall mass should be obtained. Special attention should be placed on the chronicity, size, and mobility of the mass, and on any other associated symptoms, such as pain and dyspnea. Patients often first notice the mass in the setting of coincidental trauma. Erythema, swelling, or focal tenderness of a new chest wall mass may indicate an infectious etiology. Benign chest wall neoplasms are generally mobile and soft, while malignant chest wall lesions tend to be fixed, firm, and large.
Scoliosis
Minor spinal column curves may present with discrepancies in shoulder or scapular height or waistline asymmetry. A forward bend test may reveal asymmetry in the thorax, spine, or pelvis. The test involves the patient’s bending over with feet together, legs straight, and arms hanging freely until the chest is parallel to the floor. When observed from behind the patient, asymmetric elevation of the ribs or scapula is seen in scoliosis. The simultaneous use of a scoliometer further quantifies spinal curvature.
Beware: there are other diseases that can mimic chest wall disorders:
Chest Wall Trauma
Occult pneumothoraces may arise following an initial negative chest x-ray. Other significant life-threatening trauma may occur in conjunction with chest wall trauma. With the exception of tension pneumothorax, management of these additional injuries generally takes precedence over chest wall injuries. Severe intrathoracic injuries include aortic rupture, pericardial tamponade from myocardial injury, tracheobronchial disruption, great vessel trauma, myocardial rupture, and parenchymal lung damage. Discrepancies between physical findings and the history, particularly in children, warrant a broader clinical assessment and evaluation.
Chest Wall Masses
Structures adjacent to the chest wall, such as the breast, lung, mediastinal tissues, and the pleurae, may be the source of a mass, such as via extension of a malignancy or infection. Breast and lung cancer are the most common underlying etiologies. Metastatic lesions from distant malignancies, such as carcinomas and sarcomas, may also present as chest wall masses.
Scoliosis
Differences in leg length may create pelvic and spinal asymmetry, mimicking scoliosis.
How and/or why did the patient develop a chest wall disorder?
Chest Wall Masses
Radiation exposure of the chest wall increases patients’ risk for chest wall malignancies.
Which individuals are at greatest risk of developing a chest wall disorder?
Chest Wall Trauma
Victims of blunt trauma, including patients involved in motor vehicle crashes, assaults, or falls, are at high risk for thoracic and chest wall trauma. Front seat passengers and unrestrained passengers are at higher risk of serious trauma in a motor vehicle accident.
Rib fractures are especially common in the elderly, and children who are in an unsafe home environment or who are victims of abuse are at higher risk for trauma, chest wall injuries, and rib fractures. Children are more likely to have intrathoracic injuries from thoracic trauma as a result of increased chest wall compliance. Positive pressure ventilation also puts patients at increased risk of pneumothorax.
Chest Wall Masses
Infectious masses of the chest wall are associated with intravenous drug use, use of prolonged central venous catheters, and trauma.
The genetic underpinnings of primary chest wall malignancies are complex and beyond the scope of this chapter. Women irradiated for breast cancer are at higher risk for developing radiation-induced chest wall angiosarcomas, with prevalence increasing as breast cancer survival improves.
Scoliosis
Scoliosis may affect females and young patients with immature bones more severely than it affects others.
What laboratory studies should you order to help make the diagnosis, and how should you interpret the results?
Chest Wall Trauma
Arterial blood gases are helpful; abnormal findings include respiratory acidosis in the setting of hypoventilation and metabolic acidosis with systemic hypoperfusion. A CBC may demonstrate decreased hemoglobin or hematocrit in the setting of hemorrhage. Hemoglobin might be high initially and then drop following fluid resuscitation. Thrombocytopenia may place the patient at a higher risk for bleeding.
A basic metabolic panel may be useful in evaluating the patient’s acid-base status. BUN and creatinine should be used to help determine intravascular volume status and kidney function. Elevation in serum troponin may indicate myocardial damage or contusion. The ECG may demonstrate cardiac ischemia or cardiac trauma.
Chest Wall Masses
Laboratory studies are generally not very useful in evaluating chest wall tumors. A notable exception is measurement of monoclonal immunoglobins in evaluating possible solitary plasmacytoma. Alkaline phosphatase may be elevated in osteosarcoma. Elevated ESR may be seen in Ewing’s sarcoma.
What imaging studies will be helpful in making or excluding the diagnosis of a chest wall disorder?
Chest Wall Trauma
The chest x-ray is part of the secondary survey in evaluation of the trauma victim. Interpretation should focus on evaluating for pneumothorax, hemothorax, and rib fractures, and on a general evaluation of the lungs, pleurae, ribs, sternum, clavicle, scapulae, and aortic notch. Particular attention should be paid to evaluation for a widened mediastinum and tracheal deviation. A chest x-ray is a sufficient radiographic screening study for a trauma patient who appears to be well, with no identifiable life-threatening injury. However, chest x-rays may underestimate or miss injuries.
A chest CT scan is more sensitive in detecting thoracic trauma than is a chest x-ray, particularly in distinguishing between chest wall trauma and parenchymal or mediastinal injuries. An echocardiogram may demonstrate fluid in the pleural or pericardial cavities. More recently, portable ultrasound devices have been used to evaluate for pneumothorax by assessing apposition of the visceral and parietal pleurae. Bronchoscopy, esophagoscopy, and angiography are alternative imaging modalities that may be employed in specific situations.
Chest Wall Masses
Chest x-rays usually constitute the initial imaging modality in evaluating a chest wall mass. Previous radiographs are particularly useful in assessing growth of a chest wall mass. Pathologic fractures may be seen when tumors involve the ribs. In fibrous dysplasia, medullary replacement by fibrous tissue creates a radiolucent appearance on an x-ray.
A CT scan and/or MRI is usually necessary to further evaluate chest wall masses. As a general rule, CT is best for visualizing. MRI better defines chest wall soft tissues than CT scan. Malignant lesions often show local invasion into surrounding bone or soft tissue.
Scoliosis
Chest x-rays typically underestimate the magnitude of lung impairment in kyphoscoliosis. Traditional radiographic work-up for scoliosis includes standing, full-length, postero-anterior, and lateral views of the spine. The Cobb angle is calculated from x-rays as the angle between a line drawn parallel to the cephalad end of the most superior vertebrae of the spinal curve and a line drawn parallel to the inferior aspect of the most caudal vertebrae of the curve. Multiple curves and, hence, multiple Cobb angles may be observed in one spine.
Cobb angles are not linearly related to the degree of spinal curvature; a Cobb angle of 50 degrees is associated with more than twice the curvature of a spine with a Cobb angle of 25 degrees. Skeletal maturity (Risser sign) is calculated from the x-rays based on ossification and fusion of the iliac apophysis; a score from 1 to 5 is calculated, with 5 reflecting the greatest level of skeletal maturity.
What non-invasive pulmonary diagnostic studies will be helpful in making or excluding the diagnosis of a chest wall disorder?
Scoliosis
Lung function impairment secondary to severe kyphoscoliosis is associated with decreased total lung capacity and vital capacity. The ventilation-perfusion mismatch that occurs with Cobb angles greater than 65 degrees may result in hypoxemia, with concomitant pulmonary arterial hypertension in some patients.
What diagnostic procedures will be helpful in making or excluding the diagnosis of a chest wall disorder?
Chest Wall Trauma
Needle thoracostomy may be both diagnostic and therapeutic in the setting of tension pneumothorax, although the absence of the rush of air or clinical improvement following the procedure does not exclude the diagnosis of tension pneumothorax. Needle decompression may be technically challenging or impossible in obese patients with significant chest wall soft tissue. Placement of a chest tube in the setting of either pneumothorax or hemothorax may also be diagnostic and therapeutic.
Chest Wall Masses
For lesions larger than 3 cm, whether they are suspected of being benign or malignant, excisional biopsy is performed for diagnosis and treatment. For lesions larger than 3 cm, which carry significant morbidity with resection, a preoperative tissue diagnosis is obtained. Fine needle aspiration (FNA) is useful for smaller, less concerning, chest wall masses; the procedure is relatively technically simple and may be performed in the office during initial patient evaluation. Lack of histology and tissue architecture limits the use of FNA in distinguishing many benign from malignant primary chest wall tumors.
Core needle biopsy and incisional biopsy are more invasive methods that provide tissue for histology. The procedures are performed in such a way that the biopsy track is completely excised at the time of definitive surgery. Patients may tolerate a coreneedle biopsy in the office, thereby expediting the diagnostic process.
What pathology/cytology/genetic studies will be helpful in making or excluding the diagnosis of a chest wall disorder?
Chest Wall Masses
For chest wall tumors, pathology of the tumor and nodal involvement provide a diagnosis, as well as grade, stage, size, and (potentially) prognosis. For a solitary plasmacytoma, flow cytometry may confirm the clonal nature of the cells.
If you decide the patient has a chest wall disorder, how should the patient be managed?
Chest Wall Trauma
In the setting of tension pneumothorax, successful needle decompression relieves the tension component, and should be followed immediately by conventional tube thoracostomy for definitive management. Tube thoracostomy may be all that is required for treatment of traumatic pneumothorax or hemothorax, with chest tube removed when there is no further evidence for air leak or significant fluid drainage. Surgical intervention may be necessary in the setting of ongoing air leak, significant ongoing bleeding, or persistent pneumothorax or hemothorax despite well-placed chest tubes.
Open pneumothorax is temporized by placing a dressing over the chest wound and taping on three sides, effectively creating a one-way valve that relieves tension and prevents influx of air through the chest wall. Following successful chest tube placement into the affected pleural space (at a site distinct from the chest wall wound), the dressing over the chest wall wound can be taped on all sides.
Rib fractures, particularly when multiple, may cause significant pain that impairs respiration. If incentive spirometry is limited by pain, patients may benefit from intravenous and/or epidural analgesia until symptoms improve. Flail chest associated with significant paradoxical chest wall motion can be treated with surgical stabilization of rib fractures (“rib plating”) to restore normal chest wall mechanics.
Chest Wall Masses
Benign chest wall tumors (most commonly chondroma, osteochondroma, or fibrous dysplasia) require excision only if symptomatic. Primary malignant chest wall tumors arise from bone and cartilage (55%) or soft tissue (45%). Their management depends on the type and extent of disease, but typically involves a combination of medical and surgical therapies. Malignant tumors require surgical resection (with exception of plasmacytoma), with removal of involved bone and soft tissue as necessary to achieve clear margins (1-2 cm margins for low-grade, 4 cm for high-grade). Following resection, chest wall reconstruction is critical for adequate respiratory function, wound healing, and cosmesis, and may involve mesh implantation and/or tissue transfer. In addition, most treatment regimens recommend adjuvant chemotherapy and/or radiation.
Scoliosis
Future growth is determined by age and skeletal maturity, as well as menarchal status in girls and the presence of facial hair in boys. In cases of mild kyphoscoliosis, pulmonary rehabilitation and noninvasive positive pressure ventilation may be of use in treating associated respiratory dysfunction.
Cobb angles less than 20 degrees can generally be observed, while Cobb angles between 20 and 40 degrees can either be braced or observed depending on the age of the patient, the expected future growth, and the rate of progression of the angle. Cobb angles greater than 40 degrees can be braced or treated surgically, with most patients with Cobb angles greater than 50 degrees requiring surgical intervention.
Surgical treatment involves segmental posterior fixation of the spinal column. The goal of surgery is to arrest progression of the Cobb angle (with some patients able to correct the Cobb and spinal curvature to a degree).
What is the prognosis for patients managed in the recommended ways?
Chest Wall Trauma
Prognosis and outcome depend on the severity of injury and the extent of concomitant intrathoracic and extrathoracic (e.g., head, abdominal) injuries. Isolated rib fractures almost always heal within six weeks without permanent disability. Multiple rib fractures may be associated with respiratory insufficiency and pneumonia secondary to splinting and underlying pulmonary contusion.
Chest Wall Masses
Benign chest wall tumors rarely recur following wide excision. With respect to malignant chest wall tumors, histologic grade and completeness of surgical resection are independent prognostic factors for disease-free survival. Age, gender, symptoms, and tumor size do not significantly impact survival. Malignant primary chest wall tumors carry a 60-70 percent 5-year survival rate; better outcomes are achieved by multidisciplinary, sub-specialty medical teams.
For a solitary plasmacytoma, local control is achieved in over 90 percent of patients with radiation alone; about 50 percent of patients progress to multiple myeloma within two years and require systemic treatment. Post-treatment surveillance is recommended for two years for patients with sarcomas. Isolated metastatic disease to the lungs may be treated surgically.
Scoliosis
Mild kyphoscoliosis has an excellent prognosis with supportive care only. Adolescents who undergo bracing and use the brace 23 hours a day can expect a 93 percent success rate; patients who wear the brace 8 hours a day can expect a 60 percent success rate.
Surgical patients are successfully fused 95 percent of the time with spinal angle correction in 48-93 percent of cases. Spinal curvature may continue to progress after skeletal maturity, bracing, or surgery, so patients should maintain follow-up with an orthopedic surgeon.
What other considerations exist for patients with chest wall disorders?
Chest Wall Trauma
Trauma patients often have a number of different injuries of varying severity, so it is important that physicians trained in traumatology manage the care of these patients.
Scoliosis
Adolescents with scoliosis may also carry psychosocial burdens.
Copyright © 2017, 2013 Decision Support in Medicine, LLC. All rights reserved.
No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC. The Licensed Content is the property of and copyrighted by DSM.
