Shoulder

A 38-year-old female presents to the ED with right shoulder pain after a fall directly onto that shoulder. She noticed immediate pain and difficulty moving the arm associated with mild tingling in her right fingers. The radiographs above were obtained in the ED (Image 1. AP and lateral radiographs of the right shoulder, author’s own images).

 

Anterior shoulder dislocation. You can see the humeral head inferior to the glenoid on the AP view and anterior to the scapula/glenoid on the lateral/scapular-Y view (Figure 2).

Figure 2: AP and lateral radiographs of the right shoulder. Notice the location of the humeral head in relation to the glenoid (green annotation). Author’s own images.

When ordering a shoulder x-ray, typically two views are obtained, an AP and a lateral view. The lateral view can vary, but the scapular-Y is the most useful for diagnosing shoulder dislocations (Figure 3). Additionally, a 3rd view called an axillary view (Figure 4) can be crucial to diagnosing subtle dislocations that may not be obvious on an AP or scapular-Y. [1]

  • Pitfall: Be careful with the scapular-Y view when evaluating for a shoulder dislocation. If the view is not a true/perfect lateral, the humeral head can look falsely located or dislocated. A true lateral scapular-Y view (Figure 4) will show the scapula as a line. Notice the lateral view in Figure 1 which shows some of the body of the scapula, making it an inadequate lateral view (though there is still a clear dislocation).

Figure 3: Axillary view of the glenohumeral joint with the joint in proper anatomic alignment with annotations of the anatomy (green). Case courtesy of Assoc Prof Frank Gaillard, Radiopaedia.org, rID: 7505, annotations by the author.

Scapular Y

Figure 4: True lateral scapular-Y with the glenohumeral (shoulder) joint normally aligned. Case courtesy of Assoc Prof Craig Hacking, Radiopaedia.org, rID: 37498.

  • Pearl: In addition to standard x-ray, bedside ultrasound is a valuable tool to assess for glenohumeral alignment. Using a posterior approach, the joint can be evaluated in real-time and compared to the other side to assess for initial status and post-reduction status (Figure 5).
ultrasound

Figure 5: Ultrasound views off the glenohumeral joint from the posterior approach showing normal alignment and an anterior/posterior dislocation. Courtesy of EmDocs.

Anterior shoulder dislocations are associated with a variety of other bony and soft tissue injuries as well as potential neurovascular complications. The most common injury is a Hill-Sachs lesion (humeral head indentation) and the most common nerve injury is an axillary nerve neuropraxia. While rare, Bankart lesions (glenoid chip fracture), greater tuberosity fractures, brachial plexus injuries, rotator cuff injuries, and axillary artery injuries can also occur [2].

  • Pearl: The axillary nerve innervates the skin over the deltoid, making quick evaluation easy by doing a sensory exam.

Management in the ED includes expedited reduction with neurovascular status checked before and after. There are numerous techniques for analgesia/sedation and reduction techniques. For analgesia, the patient’s presentation will dictate the necessary medications. For many patients, no or minimal analgesia can be used depending on the reduction technique. For others, intra-articular injection of lidocaine may be sufficient. For patients in extreme pain or who are unable to participate in reduction techniques, full procedural sedation may be required.

For reduction techniques, everyone has their favorite method. Generally speaking, 1-2 attempts with one method are enough to determine if that method will not work. Most methods have about the same success rates based on the literature and if one doesn’t work, trying another one is usually successful.  Traditional teaching is to get a post-reduction x-ray to confirm placement, though many recent articles have not shown benefit to this when the provider is sure of clinical reduction [3].

  • Pearl: For an in-depth review of many of the techniques, this article has extensive information with photos [4].

Orthopedics typically does not need to be consulted in the ED if the reduction is successful and there is no neurovascular compromise. If the reduction is unsuccessful despite numerous attempts and/or with sedation, a CT scan may be warranted for cross-sectional imaging of the joint to evaluate for mechanical blocks. Additionally, orthopedics may be consulted for an operative reduction under anesthesia if the reduction is unable to be completed in the ED. Follow-up with orthopedics DOES need to be established as patients will be followed and potentially offered operative repair depending on the situation

 

Resources & References:

Check out ALiEM’s Paucis Verbis cards to brush up on other can’t-miss orthopedic injuries, and SplintER Series or EMrad for more cases. For further reading about shoulder dislocations, check out WikiSM.

  1. Pak T, Kim AM. Anterior Glenohumeral Joint Dislocation. [Updated 2022 May 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK557862/
  2. Cutts S, Prempeh M, Drew S. Anterior shoulder dislocation. Ann R Coll Surg Engl. 2009;91(1):2-7. PMID: 19126329
  3. Hendey GW. Managing Anterior Shoulder Dislocation. Ann Emerg Med. 2016;67(1):76-80. PMID: 26277437
  4. Alkaduhimi H, van der Linde JA, Flipsen M, van Deurzen DF, van den Bekerom MP. A systematic and technical guide on how to reduce a shoulder dislocation. Turk J Emerg Med. 2016;16(4):155-168. PMID: 27995208.
R. Conner Dixon, MD

R. Conner Dixon, MD

Clinical Instructor
Sports Medicine Fellow
Department of Emergency Medicine
Georgetown University/Medstar Washington Hospital Center
R. Conner Dixon, MD

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Mark Hopkins, MD

Mark Hopkins, MD

Loma Linda University Health
Mark Hopkins, MD

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Alexander J. Tomesch, MD

Alexander J. Tomesch, MD

Primary Care Sports Medicine Fellow
Department of Orthopedic and Sports Medicine
University of Arizona - Tucson
Alexander J. Tomesch, MD

@DocTomesch

Emergency Medicine/Sports Medicine physician, Husband, Father, Sports Enthusiast, Craft Beer Lover. Views are my own.
Alexander J. Tomesch, MD

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