Emergency Radiology

Thrower’s Fracture of the Humerus: A Case Report

CASE REPORT:


A 35-year-old, right-handed male presented to the emergency department with complaint of right upper arm pain. He was a member of an amateur baseball team; just prior to arrival he threw a ball and immediately felt a pop and sharp pain in his right upper arm. Since that time, he had been unable to move his arm due to pain. He reported no prior injury to the arm but did state that over the last several weeks he had been having an ache in that arm. He was otherwise healthy, took no medications, denied weakness, numbness and tingling in his right arm. He was a non-smoker and an occasional drinker. He used no drugs.

Physical exam was non-focal except for the right upper extremity. His right upper arm was swollen and tender to the touch. He had decreased range of motion in his elbow and his shoulder secondary to the pain. He had an obvious deformity of the right bicep region. Distally the patient was neurovascularly intact with normal range of motion and light touch sensation intact in the wrist and hand. He had a 2+ radial pulse and capillary refill was less than 3 seconds.

The patient was given pain medication and sent for an x-ray of his right humerus. The x-ray demonstrated a displaced spiral fracture of the humerus (fig 1). The patient was placed in a coaptation splint and prior to discharge, reexamination revealed no evidence of radial nerve palsy or radial artery injury. The patient followed up with the orthopedic doctor on-call and underwent open reduction and internal fixation of his injury within 1 week (fig 2).

Figure 1. AP and oblique radiographs of the right humerus demonstrating a spiral fracture

Figure 1. AP and oblique radiographs of the right humerus demonstrating a spiral fracture

Figure 2: Right Humerus status post open reduction and internal fixation

Figure 2: Right Humerus status post open reduction and internal fixation

DISCUSSION:

This patient's presentation is consistent with a well described, but rarely observed phenomenon known as a 'Thrower's Fracture.' First reported in 1930 [1], cases have been reportedly related to everything from a baseball [2, 3], to a cricket ball [4], to a dodge ball [5], and hand grenades [6]. As with our patient, many patients who present with this injury are amateur athletes who have likely not developed adequate cortical strength of their bones as compared to professional athletes [7]. The injury is often preceded by several weeks to months of aching in the region of the humerus, which is thought to represent a stress fracture [2, 4, 8]. The complexity of the throwing motion and related transfer of forces, results in significant torque being applied to the humeral shaft, leading to a fracture, most commonly in the mid to distal third of the diaphysis.

These patients can have similar complications to any mid-shaft, spiral humeral fracture including damage to the radial artery and radial nerve [9, 10]. In these cases, given the active nature of these athletes, and if underlying complications have occurred, surgeons may elect to repair this injury surgically [2, 4, 10], though this is not always necessary given the fracture morphology.

Faculty Reviewer: Dr. Kristy McAteer

REFERENCES:

  1. Wilmoth, C., Recurrent fracture of the humerus due to sudden extreme muscular action. Journal of Bone and Joint Surgery, 1930. 12: p. 168-169.

  2. Miller, A., C.C. Dodson, and A.M. Ilyas, Thrower's fracture of the humerus. Orthop Clin North Am, 2014. 45(4): p. 565-9.

  3. Perez, A.Z., C.; Atia, H., Thrower's fracture of the humerus: An otherwise healthy 29-year-old man presented for evaluation of acute onset of severe right arm pain. Emergency Medicine, 2016. 48(5): p. 221-222.

  4. Evans, P.A., et al., Thrower's fracture: a comparison of two presentations of a rare fracture. J Accid Emerg Med, 1995. 12(3): p. 222-4.

  5. Colapinto, M.N., E.H. Schemitsch, and L. Wu, Ball-thrower's fracture of the humerus. CMAJ, 2006. 175(1): p. 31.

  6. Chao, S.L., M. Miller, and S.W. Teng, A mechanism of spiral fracture of the humerus: a report of 129 cases following the throwing of hand grenades. J Trauma, 1971. 11(7): p. 602-5.

  7. Ogawa, K. and A. Yoshida, Throwing fracture of the humeral shaft. An analysis of 90 patients. Am J Sports Med, 1998. 26(2): p. 242-6.

  8. Reed, W.J. and R.W. Mueller, Spiral fracture of the humerus in a ball thrower. Am J Emerg Med, 1998. 16(3): p. 306-8.

  9. Curtin, P., C. Taylor, and J. Rice, Thrower's fracture of the humerus with radial nerve palsy: an unfamiliar softball injury. Br J Sports Med, 2005. 39(11): p. e40.

  10. Bontempo, E. and S.L. Trager, Ball thrower's fracture of the humerus associated with radial nerve palsy. Orthopedics, 1996. 19(6): p. 537-40.

Diving Deep: Pulmonary Barotrauma in a Free Diver

Case

A 24-year-old male presented to the Emergency Department with cough and hemoptysis. The patient had been spearfishing when his symptoms began. The patient had dove to a depth of 50 feet using 11 lbs of weights on his belt, holding his breath along the way. On the way to the surface, he developed chest pain. After getting onto the boat, the patient coughed up approximately 5 tablespoons of bright red blood. After feeling a bit better, he went down again to a depth of 30 feet in order to catch a large fish. After returning to his boat, the patient was still experiencing cough, pleuritic chest pain, and mild shortness of breath.

On arrival to the emergency department, the patient was breathing comfortably on room air. He did not complain of any headache, visual changes, ear pain, nausea, joint or muscle pain, or any other symptoms. On exam, he was comfortable and his lungs were clear to auscultation bilaterally. The patient had no further hemoptysis after arrival to the emergency department. Given the patient’s chest pain and subjective shortness of breath, a chest x-ray was performed.

Chest X-ray notable for patchy, bilateral, midlung predominant airspace disease.

Chest X-ray notable for patchy, bilateral, midlung predominant airspace disease.

The patient was placed on supplemental oxygen and was admitted to the medical ICU for close monitoring overnight. Pulmonology was consulted who recommended supportive care and repeat chest x-ray the following day. A CT scan of the chest was preformed to evaluate for any underlying pulmonary parenchymal disorders.

Single image from chest CT scan showing bilateral patchy airspace disease

Single image from chest CT scan showing bilateral patchy airspace disease

A chest x-ray was completed the following morning in the medical ICU.

Chest X-ray notable for grossly stable, patchy bilateral airspace disease that is midlung predominant.

Chest X-ray notable for grossly stable, patchy bilateral airspace disease that is midlung predominant.

The patient remained hemodynamically stable and without respiratory distress throughout his hospitalization. He was discharged home on hospital day #2.

BACKGROUND PHYSICS

Spearfishing may be done while freediving, snorkeling or SCUBA diving. Our patient and his friends were freediving, or breath-hold diving.  Unlike SCUBA diving, breath-hold divers do not use supplemental air underwater.  Divers face a unique set of underwater hazards in addition to the general aquatic problems; such as drowning, hypothermia, water-borne infectious diseases, and interactions with hazardous marine life.  When diving deep, free divers are exposed to increased pressure, causing a spectrum of injuries to the body.

Pressure contributes either directly or indirectly to the majority of serious diving-related medical problems. As a diver descends underwater, absolute pressure increases much faster than in air. The pressure change with increasing depth is linear, although the greatest relative change in pressure per unit of depth change occurs nearest the surface, where it doubles in the first 33 feet of sea water. The body behaves as a liquid and follows Pascal’s law; pressure applied to any part of a fluid is transmitted equally throughout the fluid. When a diver submerges, the force of the tremendous weight of the water above is exerted over the entire body. The body is relatively unaware of this change in pressure.

Pascal’s Law: pressure applied to any part of a fluid is transmitted equally throughout the fluid.  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/2/27/Pascals-law.svg/2000px-Pascals-law.svg.png

Pascal’s Law: pressure applied to any part of a fluid is transmitted equally throughout the fluid.

Source: https://upload.wikimedia.org/wikipedia/commons/thumb/2/27/Pascals-law.svg/2000px-Pascals-law.svg.png

This is true of the body, however the spaces within the body that contain air, including the lungs, sinuses, intestines, and middle ear follow a different law. The gases in these spaces obey Boyle's law; the pressure of a given quantity of gas at constant temperature varies inversely with its volume. Therefore, as you dive deeper, the volume of air in the middle ear, sinuses, lungs, and gastrointestinal tract is reduced. Inability to maintain gas pressure in these body spaces equal to the surrounding water pressure leads to barotrauma.

Boyle’s Law: the pressure of a given quantity of gas at constant temperature varies inversely with its volume.  Source: https://upload.wikimedia.org/wikipedia/commons/2/25/2314_Boyles_Law.jpg

Boyle’s Law: the pressure of a given quantity of gas at constant temperature varies inversely with its volume.

Source: https://upload.wikimedia.org/wikipedia/commons/2/25/2314_Boyles_Law.jpg

Barotrauma can potentially involve any area with entrapment of gas in a closed space. In addition to sinuses, lungs and the GI tract, the barotrauma can occur to the external auditory canal, includes teeth, the portion of the face under a face mask, and skin trapped under a wrinkle in a dry suit. The tissue damage resulting from such pressure imbalance is commonly referred to as a “squeeze”. 

Given that our patient’s only complains were respiratory in nature; hemoptysis, shortness of breath, cough with deep breathing, we will focus on pulmonary barotrauma. Pressure related injury to lung can occur on the way down or as a diver ascends to the surface.

 

LET’S DIVE DEEPER

Recall from physiology that if you were able to completely exhale, the absolute minimum lung volume remaining is called the residual volume (RV). Lung squeeze occurs when the when the diver descends to a depth at which the total lung volume is reduced to less than the residual volume. At this point, transpulmonic pressure exceeds intraalveolar pressure, causing transudation of fluid or blood from ruptured of pulmonary capillaries. (1) Patients exhibit signs of pulmonary edema and hypoxemia.

Lung Volumes  Source: https://upload.wikimedia.org/wikipedia/commons/8/8c/Vital_Capacity.png

Lung Volumes

Source: https://upload.wikimedia.org/wikipedia/commons/8/8c/Vital_Capacity.png

Despite this presumed mechanism of barotrauma of descent, free divers are able to dive to depths beyond those that should cause mechanical damage to the lungs. Other physiologic mechanisms must play a role, although the exact pathophysiology of this condition remains unclear. When diving deep, the chest cavity itself gets smaller and there is central pooling of blood in the chest from the surrounding tissues. The central pooling of blood in the chest equalizes the pressure gradient when the RV is reached and thereby decreases the effective RV. This mechanism increases the pressure in the pulmonary vascular bed causing rupture of the pulmonary capillaries and intrapulmonary hemorrhage. This is the reason that many free divers cough up blood after deep dive. These mechanisms allow the lungs to be compressed down to about 5% of Total Lung Capacity in highly-trained breath-hold champions. (2) Although there are several  case reports of lung squeeze occurring with shallow diving, typically with repetitive dives with short surface intervals. (3) An individual’s anatomy, physiologic reserves, underlying pathology and the conditions of the day all play a role in the development of pulmonary barotrauma. (2)

RESURFACING

As a diver ascends, the pressure within the alveoli of the lung increase as the pressure around the diver decreases. Remember Boyle’s law? If intrapulmonary gas is trapped behind a closed glottis, as the diver ascends and the surrounding pressure decreases, the volume of the intrapulmonary gas increases. Increased pressure within the lung causes an increase in transalveolar pressure leading to overexpansion injury and alveolar rupture. (4) A situation of rapid ascent to the surface, such as if a diver runs out of air, panics, or drops his weights, is often the cause of pulmonary barotrauma of ascent. Divers who hold a breath as they ascend and those with obstructive airway diseases, such as asthma or chronic obstructive pulmonary disease, are at increased risk. This was likely the case with our patient, he did not exhale and relieve the building pressure as he ascended, causing his pulmonary barotrauma.

Eventually, the intrapulmonary pressure rises so high that air is forced across the pulmonary capillary membrane. The specific clinical manifestations of pulmonary barotrauma depend on the amount of air that escapes the alveoli and location that it travels to. Air can rupture alveoli, causing localized pulmonary injury and alveolar hemorrhage. (4) Pulmonary interstitial air can dissect along bronchi to the mediastinum causing pneumomediastinum, the most common form of pulmonary barotrauma. This air can track superiorly to the neck, resulting in subcutaneous emphysema. Rarely, air may reach the visceral pleura, causing a pneumothorax.

If air enters the pulmonary vasculature, it can travel to the heart and embolize to other parts of the body, causing arterial gas embolism (AGE). Clinical manifestations of cerebral air embolism are sudden and can be life-threatening. Approximately 4% of divers who suffer an AGE die immediately from Total occlusion of the central vascular bed with air. (5,6) AGE patients who make it to the hospital usually present with hemoconcentration due to plasma extravasation from endothelial injury. (7)  The degree of hemoconcentration correlates with the neurologic outcome of the diver. (7) Creatinine kinase is elevated in cases of AGE and correlates with neurologic outcome of the diver. (8) All cases of AGE must be referred for hyperbaric oxygen treatment as rapidly as possible. (9) All suspected AGE patients should be referred for hyperbaric consultation, even if initial neurologic manifestations resolve prior to reaching an ED in order to prevent progression of subtle neurologic deficits that are not immediately detected.

Our patient dove to a depth of 50 feet and reported holding his breath while resurfacing, therefore it is likely that he experienced pulmonary barotrauma of ascent. However, cases of lung squeeze have occurred with free diving to more shallow depths. (3) Regardless, the emergency department management of the spectrum of pulmonary barotrauma is similar.

 

MANAGEMENT OF PULMONARY BAROTRAUMA

First of all, stop the dive! Ensure the safety of the injured diver and help them relax. Help the injured diver exit the water to prevent any strenuous physical activity. When available, have the diver breath 100% oxygen. Avoid exposure to pressures (such as flying or a repeat dive). On arrival to the ED, perform a complete history and physical. Evaluate for any signs of AGE, such as a transient episode of neurologic dysfunction immediately after surfacing.  

A diver with local pulmonary injury without any evidence of AGE does not require recompression and should be treated with supportive care, consisting of rest and supplemental oxygen in severe cases. Most diving-related pneumothoraces are small, therefore treatment may consist simply of supplemental oxygen and close observation. If the diver requires recompression, a chest tube must be placed in order to prevent a tension pneumothorax during depressurization from a hyperbaric chamber. Depending on where you practice, consider transferring the patient to a tertiary care facility if the clinical presentation is worsening, if there are further episodes of hemoptysis, or if the patient requires further testing, such as broncoscopy. To date, I have been unable to find any data that supports the use of steroids, diuretics, or other medications to treat this condition. Patients should rest for at least two weeks before resuming diving and preferably after being cleared fit to dive by a physician with knowledge of dive related injuries.

NEED SOME ADVICE?

Divers Alert Network (DAN) is a not-for-profit diving safety medical organization. DAN's medical staff is on call 24 hours a day, 365 days a year, to handle diving emergencies. They can be reached via DAN.org and through a medical hotline 1-919-684-9111.

TAKE HOME POINTS

  • Pressure contributes to the majority of diving-related medical problems.

  • The spaces within the body that contain air, including the lungs, sinuses, intestines, and middle ear obey Boyle's law; the pressure of a given quantity of gas at constant temperature varies inversely with its volume.

  • As you dive deeper, air in the middle ear, sinuses, lungs, and gastrointestinal tract is reduced in volume. As you resurface, the pressure of the gas decreases and the volume expands.

  • When breath-hold diving to deep depths, divers may experience “lung squeeze”, or transudation of fluid or blood from ruptured pulmonary capillaries causing non-cardiogenic pulmonary edema.

  • On ascent, over distension causes alveolar rupture and may cause air to escape into an extraalveolar locations.

    • Possible presentations are pneumomediastinum, subcutaneous emphysema, pneumothorax, or arterial gas embolization.

  • Treatment usually consists of supportive care, rest, avoiding further exposure to pressures (flying or repeat dives), and supplemental oxygen when needed.

  • Evaluate for any historical clues of physical exam findings suggestive of AGE as these patients require hyperbaric treatment.

  • When in doubt, call the 24-hour Divers Alert Network (DAN) emergency medical hotline at 1-919-684-9111.

Faculty Reviewers: Dr. Kristina McAteer and Dr. Victoria Leytin

Follow the discussion here on Figure 1

SOURCES

  1. Schaefer KE, Allison RD, Dougherty JH, Jr., et al. Pulmonary and circulatory adjustments determining the limits of depths in breathhold diving. Science 1968;162:1020-3.

  2. Lung Squeeze: Coughing your lungs out...or not! 2015. (Accessed July 15, 2018, at https://alertdiver.eu/en_US/articles/lung-squeeze-coughing-your-lungs-out-or-not.)

  3. Raymond LW. Pulmonary barotrauma and related events in divers. Chest 1995;107:1648-52.

  4. Balk M, Goldman JM. Alveolar hemorrhage as a manifestation of pulmonary barotrauma after scuba diving. Ann Emerg Med 1990;19:930-4.

  5. Van Hoesen K., Lang, M. Diving Medicine.  Auerbach’s Wilderness Medicine. 7th ed: Elsevier, Inc.; 2017:1583-618.

  6. Neuman TS, Jacoby I, Bove AA. Fatal pulmonary barotrauma due to obstruction of the central circulation with air. J Emerg Med 1998;16:413-7.

  7. Smith RM, Van Hoesen KB, Neuman TS. Arterial gas embolism and hemoconcentration. J Emerg Med 1994;12:147-53.

  8. Smith RM, Neuman TS. Elevation of serum creatine kinase in divers with arterial gas embolization. N Engl J Med 1994;330:19-24.

  9. Cales RH, Humphreys N, Pilmanis AA, Heilig RW. Cardiac arrest from gas embolism in scuba diving. Ann Emerg Med 1981;10:589-92.

Hiding in Plain Sight: Unexpected Findings on Chest X-Ray

Rich Gorilla CT.jpg

Notice anything unusual about this scan? In a study by Melissa Trafton Drew and Jeremy Wolfe, 83% of radiologists didn't notice the gorilla in the top right portion of this image when scrolling through five chest CT scans looking for lung nodules. (1) This is thought to be due to a phenomenon known as inattention blindness. When engaged in a demanding task, we may fail to perceive an unexpected stimulus that is in plain sight. If you don’t believe me, check this out:

The chest x-ray is one of the most commonly performed imaging tests. As emergency medicine physicians, we order chest x-rays to evaluate patients with a wide variety of complaints. Often times, it is our responsibility to interpret the x-ray and create a management plan before a radiologist has a chance to look at the image. This is true in community hospitals without radiologists available during night or weekend hours, in critically ill patients, or in trauma victims at large academic centers. Several studies have shown a discrepancy between the x-ray readings of emergency medicine physicians verses radiologists. (2,3,4,5) There is wide variability in the rate of misinterpretations reported, depending on the type of imaging, the experience level of the clinician, and the difficulty level of the chest x-ray findings, among other factors.

Chest x-ray interpretation is a vital skill as interpretation errors can have significant consequences.  False negatives may result in missing life-threatening conditions and worse patient outcomes. False positives may result in further testing, longer ED course and unnecessary interventions.  We are taught to be systematic in our approach to reading an image. However, it is not uncommon to zero in on the part of the chest x-ray we are interested in and unintentionally brush over the rest of the picture. This can lead to missed diagnoses and poorer patient outcomes.

With the importance of accurate chest x-ray interpretation skills in mind, let’s take a step back and review the basics:

The ABC's of Reading a Chest X-ray: 

First- check the patient information, the projection (AP or PA), the date it was taken. Review the aspects that affect the quality of the film.

  • Check the alignment (medial ends of clavicle equidistant from spinous process)
  • Check the inspiratory effort (10-11 posterior ribs in each lung field)
  • Exposure (is the image too bright or too dark? The vertebrae should be visible behind the heart)

Remember the pneumonic “RIPE” to evaluate the quality of an image - Rotation, Inspiration, Projection, Exposure. 

https://commons.wikimedia.org/wiki/File:Mediastinal_structures_on_chest_X-ray.svg#/media/File:Mediastinal_structures_on_chest_X-ray,_annotated.jpg

https://commons.wikimedia.org/wiki/File:Mediastinal_structures_on_chest_X-ray.svg#/media/File:Mediastinal_structures_on_chest_X-ray,_annotated.jpg

When ready to review the x-ray, consider the commonly used “A, B, C, D, E, F” system.

A - Airway- trachea, carina, right and left main bronchi

B - Bones and soft tissue- clavicles, ribs- posterior rand anterior, vertebral bodies, and sternum on lateral films. Look for any fractures, dislocations, or lytic lesions.

C - Cardiac- cardiac silhouette and mediastinum. The cardiac silhouette should be less than half of the thoracic cavity. AP films exaggerate heart size, so this rule does not apply. Assess the borders of the heart and the hilar structures

D - Diaphragm- right should be higher than left and you should see a gastric air bubble on the left. Is there any free air under the diaphragm? Evaluate the costophrenic angle and pleura (normally invisible due to thinness).

E - Everything else (lines and tubes, pacemakers, artificial valves)

F - Fields- FINALLY, evaluate the lung fields. Lungs are the area of greatest interest, so it is helpful to keep this at the end to prevent distraction. Divide each lung into three “zones” when reading a chest x-ray. These do not correlate with the lobes. Remember, there are 2 lobes on the left (upper and lower) and 3 on the right (upper, middle and lower). 

https://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/2312_Gross_Anatomy_of_the_Lungs.jpg/1280px-2312_Gross_Anatomy_of_the_Lungs.jpg

https://upload.wikimedia.org/wikipedia/commons/thumb/7/7e/2312_Gross_Anatomy_of_the_Lungs.jpg/1280px-2312_Gross_Anatomy_of_the_Lungs.jpg

There are several things that do not fit perfectly into the A-E categories.

  • Apices
    • Look again at the lung above the clavicles
  • Retrocardiac space
    • Look for consolidation or a mass in this region
  • Below the diaphragm
    • Remember that the lungs extend below the diaphragm posteriorly. Look out for consolidation or lesions on the lateral film.
  • Soft-tissue abnormalities
    • Don’t forget to look for air, foreign bodies, and other soft tissue abnormalities.

Now that we have refreshed your memory, it’s time to practice! Imagine that you are in a small community setting, working the overnight shift. There are no radiologists available until the morning and it is up to you to read the chest x-ray.

Go through the examples below and see what findings you can pick up on these chest x-rays.


Case 1: Find the abnormality.

Case 1 answer: This patient has pneumomediastinum. Air appears as curvilinear lucencies outlining the mediastinum. Note the continuous diaphragm sign- the entire diaphragm is visualized as air in the mediastinum separates the heart and the superior surface of the diaphragm.

Case 2: Find the abnormality

Case 2 answer: This patient has a left shoulder dislocation. The humeral head is displaced from the glenoid of the scapula.

Case 3: Find the abnormality

Case 3 answer: This patient has a right middle lobe collapse. This is easier to visualize on the lateral view, where a triangular opacity overlying the cardiac silhouette can be seen. It can be difficult to see a middle lobe collapse on frontal projections. You may notice that the horizontal fissure is no longer visible or that there is blurring of the right heart border. (6)

For more information, check out https://radiopaedia.org/articles/right-middle-lobe-collapse


Case 4: Find the abnormality 

Case 4 answer: The central line placed in the right neck soft tissue crosses the midline. This line was placed in the carotid artery.
https://pbs.twimg.com/media/CmVRNRzVIAQCaf9.jpg

https://pbs.twimg.com/media/CmVRNRzVIAQCaf9.jpg


Case 5: Find the abnormality

Case 5 answer: Misplaced tooth. Notice the ovoid, radiopaque foreign body in the right mainstem bronchus.

Case 6: Find the abnormality

Case 6 answer: This patient has a left lower lobe pneumonia. There is a positive spine sign on the lateral projection. The spine normally becomes more radiolucent as you progress inferiorly given the increased amount of air containing lung overlying the spine as you travel downwards. Where there is fluid, a mass, or a consolidation in the lower lung fields, the vertebral bodies appear more radiodense.  

For more information, check out http://learningradiology.com/notes/chestnotes/spinesign.htm and https://radiopaedia.org/cases/left-lower-lobe-pneumonia-10


Case 7: Find the abnormality

https://images.radiopaedia.org/images/627328/6743f24a87021f15266d7385963870_big_gallery.jpg

https://images.radiopaedia.org/images/627329/afc5beac8649e5e1fed60df4863281_big_gallery.jpg

Case 7 answer: This patient has Chilaiditi syndrome. In this syndrome, the colon is positioned between the liver and the diaphragm which can appear as free air under the diaphragm. Notice the rugal folds, this helps differentiate bowel containing gas from free air.

For more information, check out: https://radiopaedia.org/articles/chilaiditi-syndrome

Another example of Chilaiditi Syndrome:

https://upload.wikimedia.org/wikipedia/commons/6/6c/Chilaiditi_obvious.jpg

https://upload.wikimedia.org/wikipedia/commons/6/6c/Chilaiditi_obvious.jpg

Here is an example of actual pneumperitonium:

https://upload.wikimedia.org/wikipedia/commons/3/3c/Pneumoperitoneum_modification.jpg

https://upload.wikimedia.org/wikipedia/commons/3/3c/Pneumoperitoneum_modification.jpg


Case 8: Find the abnormality.

https://upload.wikimedia.org/wikipedia/commons/thumb/9/98/Pneumothorax_im_liegen.jpg/689px-Pneumothorax_im_liegen.jpg

Case 8 answer: This patient has a left pneumothorax. This patient is supine at the time of this image (like many of our back-boarded and collared trauma patients). Notice the abnormally deep costophrenic angle on the left. This is known as the deep sulcus sign and is present because air collects in the non-dependent potions of the pleural space (anteriorly and basally when the patient is supine, apex when the patient is upright).

Case 9: Find the abnormality:

http://image.wikifoundry.com/image/1/UyT1bPAhr9Ui2Q1JlkLj_w115368/GW500H488

Case 9 Answer: This x-ray is NORMAL. It looks like this patient has a left pneumothorax on first glance, but the pleural line you think you see is actually a skin fold. (7) Notice that the pulmonary vessels extend to the outer edge of the lung fields.

For more information, check out: http://www.wikiradiography.net/page/Patterns+of+Misdiagnosis+in+Plain+Film+Radiography section 16 on artifacts.


Case 10: Find the Abnormality.

Case 10 Answer: The OGT is malpositioned and is entering the right mainstem bronchus and terminating in the right lung.

Case 11: Find the Abnormality.

https://radiopaedia.org/cases/scapular-fracture-11

Case 11 Answers: There is a comminuted fracture through the body of the right scapula. Fractures of the scapula usually occur in association with injuries to the ipsilateral lung, thoracic cage and shoulder girdle. Presence of a scapula fracture mandates further investigation for associated injuries. (8)

Case 12: Find the abnormality.

Case 12 Answer: This patient has extensive pneumomediastinum extending cranially into the neck. There is extensive soft tissue emphysema about the chest wall. This occurred after a coughing fit (believe it or not). No evidence of pneumonia or pneumothorax is seen, although it is difficult to visualize the lung fields with the overlying subcutaneous emphysema.

Conclusion

Chest x-ray interpretation is a vital skill as errors can lead to missed diagnoses and worse patient outcomes. Adopt a systemic approach to reading a chest x-ray and use it every single time. Use the ABCDEF pneumonic to guide your interpretation and to avoid overlooking an abnormality that are hiding in plain sight.

Faculty Reviewer: Robert Tubbs, MD

References

  1. Drew T, Vo ML, Wolfe JM. The invisible gorilla strikes again: sustained inattentional blindness in expert observers. Psychol Sci 2013;24:1848-53.
  2. Petinaux B, Bhat R, Boniface K, Aristizabal J. Accuracy of radiographic readings in the emergency department. Am J Emerg Med 2011;29:18-25.
  3. Safari S, Baratloo A, Negida AS, Sanei Taheri M, Hashemi B, Hosseini Selkisari S. Comparing the interpretation of traumatic chest x-ray by emergency medicine specialists and radiologists. Arch Trauma Res 2014;3:e22189.
  4. Soudack M, Raviv-Zilka L, Ben-Shlush A, Jacobson JM, Benacon M, Augarten A. Who should be reading chest radiographs in the pediatric emergency department? Pediatr Emerg Care 2012;28:1052-4.
  5. Nitowski LA, O'Connor RE, Reese CLt. The rate of clinically significant plain radiograph misinterpretation by faculty in an emergency medicine residency program. Acad Emerg Med 1996;3:782-9.
  6. Right Middle Lobe Collapse. at https://radiopaedia.org/articles/right-middle-lobe-collapse.)
  7. Patterns of Misdiagnosis in Plain Film Radiography. at http://www.wikiradiography.net/page/Patterns+of+Misdiagnosis+in+Plain+Film+Radiography.)
  8. Baldwin KD, Ohman-Strickland P, Mehta S, Hume E. Scapula fractures: a marker for concomitant injury? A retrospective review of data in the National Trauma Database. J Trauma 2008;65:430-5.