SGEM#288: Crazy Game of POCUS to Diagnose Shoulder Dislocations

Date: March 27th, 2020 Reference: Secko et al. Musculoskeletal Ultrasonography to Diagnose Dislocated Shoulders: A ProspectiveCohort. Ann Emerg Med Feb 2020 Guest Skeptic: Dr. Tony Zitek is an Emergency Medicine physician in Miami, Florida. He is an Assistant Professor of Emergency Medicine for Florida International University and Nova Southeastern University, and Tony is the Research Director for the Emergency Medicine residency program at Kendall Regional Medical Center. DISCLAIMER: THIS IS NOT AN EPISODE ON COVID19 Here are five websites to get up-to-date information about COVID19: Centre for Disease Control and Prevention Health Canada Public Health Ontario World Health Organization Food and Drug Administration Case: An 18-year-old, previously healthy male presents to the emergency department after sustaining an injury to his right shoulder after colliding with another player during a football game.  On examination, there is a loss of the normal rounded appearance of the shoulder.  You suspect the patient may have a shoulder dislocation.  He has no history of shoulder dislocations in the past.  Will you order an x-ray or perform a point-of-care ultrasound to confirm the diagnosis? Background: Despite shoulder dislocations being a very common injury presenting to the ED, it has only been covered once on SGEM#121. This episode tried to answer whether it was better for the shoulder to be immobilized in an external or internal rotation post-reduction. We still don’t know if one position is superior to another. Emergency physicians frequently perform pre- and post-reduction x-rays for patients with shoulder dislocations.  However, some prior studies suggest that the routine performance of these x-rays may not be necessary, especially in patients with recurrent dislocations who have not sustained any direct trauma [1-2]. Point-of-care ultrasound (POCUS) has previously been studied for the use of the diagnosis of shoulder dislocations with most prior data suggesting that POCUS is highly sensitive and specific for the diagnosis of shoulder dislocations [3-4]. As with other applications of POCUS, the use of ultrasound for shoulder dislocations has the potential to reduce the time to diagnosis, reduce radiation exposure, and lower cost.  However, prior studies about the use of POCUS for shoulder dislocations have used a variety of scanning techniques and some have utilized as few as 2 sonographers [4].  One study found only a 54% sensitivity for identifying persistent dislocation after a reduction attempt [5]. Clinical Question: What is the diagnostic accuracy of point-of-care ultrasound for the diagnosis of shoulder dislocations as compared with x-ray? Reference: Secko et al. Musculoskeletal Ultrasonography to Diagnose Dislocated Shoulders: A Prospective Cohort. Ann Emerg Med Feb 2020 Population: Adult patients with suspected shoulder dislocations who presented to one of two EDs when a study investigator was present. Exclusion: Patients with multiple traumatic injuries, decreased level of consciousness, or hemodynamic instability. Intervention: Pre- and post-reduction POCUS utilizing a posterior approach in which they traced the scapular spine towards the glenohumeral joint. The POCUS technique they used is basically as follows --- the sonographer palpates the spine of the scapula, and then places the ultrasound probe directly over the scapular spine. The study protocol allowed the sonographer to choose either a linear or curvilinear probe. The sonographer then follows the scapular spine laterally until the glenoid and humerus are identified. Using this technique, the glenoid and humeral head both look like hyperechoic semicircles. They should be very close to each other, and if not, that indicates a shoulder dislocation. After assessing for dislocation, the sonographer can assess for fracture by fanning the probe from a cephalic...