Sternoclavicular Joint Dislocation: Serious concern or not a big deal?

Case

A healthy 8-year-old girl was playing basketball and fell forward onto the anterior aspect of her right shoulder. When she rotates her shoulder in a circular motion, she feels a “popping” sensation in the middle of her chest. Her mother further notes a slight deformity near the center of her chest. She reports no other injuries and is not currently in pain.

Exam

Well-developed young female in no acute distress with full range of motion of her right shoulder. There is a palpable deformity at the right sternoclavicular joint without tenderness. A reproducible pop is evident with circumduction of the right shoulder. Neurovascular exam is normal. Skin is intact.

Clinical image showing a protrusion over the right SCJ. Corresponding AP plain film demonstrating widening of the SCJ

Clinical image showing a protrusion over the right SCJ. Corresponding AP plain film demonstrating widening of the SCJ

Diagnosis

Anterior sternoclavicular joint dislocation

Treatment

Sling for support/comfort, and outpatient orthopedics follow-up.

About Sternoclavicular Joint (SCJ) Dislocations

KaineJ Ortho Figure 3.jpg

The SCJ is the only true articulation of the upper extremity with the axial skeleton. It is a well-supported joint with multiple ligamentous attachments to surrounding structures and thick anterior/posterior sternoclavicular ligaments. Note that the joint closely overlies the vascular and airway structures of the mediastinum.

Injuries to the SCJ are rare, comprising less than 1% of all joint dislocations and only 3% of shoulder girdle injuries. The SCJ can be dislocated anteriorly or posteriorly.  A thorough neurovascular examination of the affected extremity is essential given the clavicle’s proximity to the brachial plexus and important vascular structures. SCJ injuries may include physeal fractures in young patients (the physis doesn’t fuse until the early to middle twenties!). CT is typically favored as the imaging modality of choice over plain radiographs.

Mechanism of injury

  • Direct - force applied to the medial aspect of the clavicle forces it posteriorly (i.e., MVC or when one athlete falls on top of another)
  • Indirect - force applied to the shoulder and is transmitted medially (commonly seen in football pileups or falls on an outstretched arm)
A - A posterior SCJ dislocation caused by a force applied to the posterolateral aspect of the shoulder. B - An anterior SCJ dislocation caused by a force applied to the anterolateral aspect of the shoulder.

A - A posterior SCJ dislocation caused by a force applied to the posterolateral aspect of the shoulder.

B - An anterior SCJ dislocation caused by a force applied to the anterolateral aspect of the shoulder.

Anterior dislocation

  • The more common type of SCJ dislocation.
  • Largely a cosmetic defect, with minimal functional impairment in mild to moderate cases.
  • Most patients can be treated conservatively with a sling, NSAIDs, and ice. This typically results in a favorable outcome with the joint stabilizing in the subluxed position. Patients can be pain free in as little as 2-3 weeks and have full return to unrestricted activity by 3 months (~80% of patients show no functional impairment).
  • Closed reduction can be attempted. However, re-dislocation rates range from 21% - 100%.
  • Rarely is operative reduction indicated and, when performed, has mediocre outcomes.

Posterior dislocation – an orthopedic emergency

  • Less common than anterior SCJ dislocation.
  • 30% of posterior dislocations are associated with life-threatening complications due to mediastinal injury.
  • Extent of injury is best characterized by CT angiogram.
  • Emergent consultation of orthopedic surgery is recommended.
  • Reduction is best performed by orthopedics in the OR with vascular surgery readily available.
  • However, in the event of a pulseless limb, consider emergent reduction in the ER.
Axial CT image showing retropulsion of the medial aspect of the left clavicle behind the manubrium with potential compromise of the mediastinal structures. The corresponding anatomical diagram highlights the structures at risk.

Axial CT image showing retropulsion of the medial aspect of the left clavicle behind the manubrium with potential compromise of the mediastinal structures. The corresponding anatomical diagram highlights the structures at risk.

The most common reduction technique involves placing towels between the patient’s shoulder blades. Then, traction is applied to the affected arm while holding it in abduction (90 degrees) and extension (15 degrees). An assistant may be required to apply manual pressure to the medial aspect of the clavicle to facilitate reduction of an anterior dislocation. Similarly, an assistant may use a towel clip to percutaneously grasp a posteriorly dislocated clavicle and apply forward traction.

The most common reduction technique involves placing towels between the patient’s shoulder blades. Then, traction is applied to the affected arm while holding it in abduction (90 degrees) and extension (15 degrees). An assistant may be required to apply manual pressure to the medial aspect of the clavicle to facilitate reduction of an anterior dislocation. Similarly, an assistant may use a towel clip to percutaneously grasp a posteriorly dislocated clavicle and apply forward traction.

Take Home Points

  • Sternoclavicular joint injuries are rare injuries.
  • In younger patients be careful to look for physeal fracture and displacement.
  • Anterior dislocations can be conservatively managed and have favorable outcomes.
  • Posterior dislocations can be life threatening and require emergent orthopedic consultation.

Faculty Reviewer: Jeffrey P. Feden, M.D.

 

References

Morell DJ, Thyagarajan DS. Sternoclavicular joint dislocation and its management: A review of the literature. World J Orthop 2016 April 18; 7(4): 244-250

Jiang W, Gao Sg, Li Ys, Lei Gh. Bipolar dislocation of the clavicle. Indian J Orthop 2012;46:721-4

Roepke, Clare et al. Chest Pain Bounce-Back: Posterior Sternoclavicular Dislocation Annals of Emergency Medicine, Volume 66 , Issue 5 , 559 - 561

Bjoernsen, LP, Ebinger, A. Shoulder and Humerus Injuries. In: Tintinalli’s Emergency Medicine. 8th ed. New York: McGraw-Hill; 2016

Bengtzen, R, Daya, M. Shoulder. In: Rosen's emergency medicine: concepts and clinical practice 9th edition. Philadelphia, PA: Mosby/Elsevier; 2017

Egol, KA, Koval, KJ, Zuckerman, JD. Acromioclavicular and Sternoclavicular Joint injuries. In: Handbook of Fractures. 5th ed. Philadelphia, PA : Wolters Kluver; 2014

Thurston,M, Jones, J, et al. Sternoclavicular joint dislocation [Internet]. [Accessed August 15, 2017]. Available from: https://radiopaedia.org/articles/sternoclavicular-joint-dislocation

Cadogan, M. Sternoclavicular Joint Dislocation [Internet]. 2014. [Accessed on August 15, 2017]. Available from: https://lifeinthefastlane.com/sternoclavicular-joint-dislocation.

Weatherford, B. Sternoclavicular Dislocation [Internet] [Accessed on August 15, 2017]. Available from: http://www.orthobullets.com/trauma/1009/sternoclavicular-dislocation

AEM Early Access 10: Air Ambulance Delivery and Administration of 4-Factor PCC

Welcome to the tenth episode of AEM Early Access, a FOAMed podcast collaboration between the Academic Emergency Medicine Journal and Brown Emergency Medicine. Each month, we'll give you digital open access to an recent AEM Article or Article in Press, with an author interview podcast and suggested supportive educational materials for EM learners.

Find this podcast series on iTunes here.

        A FOAM Collaboration: Academic Emergency Medicine Journal and Brown EM

        A FOAM Collaboration: Academic Emergency Medicine Journal and Brown EM

DISCUSSING:

Air Ambulance Delivery and Administration of Four-Factor Prothrombin Complex Concentrate is Feasible and Decreases Time to Anticoagulation Reversal. Claire Vines, PharmD, Stephanie J. Tesseneer, PharmD, Robert D. Cox, MD, PhD,
Damon A. Darsey, MD, Kristin Carbrey, PharmD, BCPS and Michael A. Puskarich, MD

(click on title for full text; open access through February 1, 2018)     

LISTEN NOW: INTERVIEW WITH corresponding AUTHOR DR.michael puskarich

Dr. Michael Puskarich

Michael Puskarich, MD

Associate Professor and Research Director

Department of Emergency Medicine

University of Mississippi Medical Center

ARTICLE SUMMARY:

Objectives: The objective was to evaluate the feasibility, safety, and preliminary efficacy of four-factor prothrombin complex concentrate (4-factor PCC) administration by an air ambulance service prior to or during transfer of patients with warfarin-associated major hemorrhage to a tertiary care center for definitive management (interventional arm) compared to patients receiving 4-factor PCC following transfer by air ambulance or ground without 4-factor PCC treatment (conventional arm).

Methods: This was a retrospective chart review of patients presenting to a large academic medical center. All patients presenting to the emergency department (ED) treated with 4-factor PCC from April 1, 2014, through June 30, 2016, were identified. For this study, only transfer patients with an International Normalized Ratio (INR) > 1.5 actively treated with warfarin were included. The primary outcome was the proportion of patients with an INR ≤ 1.5 upon tertiary care hospital arrival, and the secondary efficacy outcome was difference in time to achievement of INR ≤ 1.5. Additional safety and efficacy objectives included difference in thromboembolic complications, length of stay, intensive care unit length of stay, and inpatient mortality between groups.

Results: Of the 72 included patients, a higher proportion of patients in the interventional group had an INR ≤ 1.5 on ED arrival (proportion difference = 0.82, 95% confidence interval = 0.64–0.92, p < 0.0001) and significantly reduced time to observed INR ≤ 1.5 (181 minutes vs. 541 minutes, p = 0.001). No differences were observed in thromboembolic complications or patient-centered outcomes with the exception of mortality, which was significantly higher in patients in the interventional group. This group was also observed to have lower Glasgow Coma Scale score and higher intubation rates prior to transfer and treatment.

Conclusions: Dispatch of an air ambulance carrying 4-factor PCC with administration prior to transfer is feasible and leads to more rapid improvement in INR among patients with warfarin-associated major hemorrhage.

FURTHER READING:

Race against the clock: overcoming challenges in the management of anticoagulant-associated intracerebral hemorrhageJ Neurosurg. 2014 Aug;121 Suppl:1-20. doi: 10.3171/2014.


 

Ultrasound Case of the Month

Case

This is a 56-year old female, with a PMH of breast cancer, who presented to the Emergency Department with shortness of breath and chest pain for one day. Her symptoms are not exertional or positional, and the pain is not pleuritic. There is no personal or family history of coronary artery disease. She denies having a history of similar symptoms in the past. She denies fevers, chills, abdominal pain, nausea, vomiting, or lower extremity edema.

Diagnosis

Saddle pulmonary embolism with evidence of right heart strain and left lower extremity deep vein thrombosis.

Video

Discussion

The above images demonstrate evidence of right heart strain from a saddle pulmonary embolism. A parasternal long axis view was obtained, and we are able to see enlargement of the right ventricle.  In the parasternal long, the probe marker is pointed to the patients right shoulder, and the RV is the ventricle on the top of the screen, as it is the most anterior chamber in the heart and will be closest to the probe. In the parasternal long view, the RV, aortic outflow tract and the LA should all be approximately equal in size.  In a patient with clinical suspicion of PE, a large RV is concerning. In the apical 4 chamber view, the RV/LV ratio should be about 0.6:1 measured across the base of the chambers.  More simply, the RV should be small than the LV. If it is equal in size or larger, this represents RV enlargement.  

Despite the fact that this patient did not report any lower extremity swelling, an ultrasound of the lower extremities was performed in order to find the potential source of the patient’s PE. Starting proximally in the inguinal region, locate the femoral vein at the greater saphenous junction.  You should compress above at and below this junction, and then continue to compress in 1cm increments moving distally as far as you can, but at least until you see the split of the femoral vein and the deep femoral vein.

In the above ultrasound images, the left popliteal vein was non-compressible. We were able to visualize clot within the lumen of the vessel, confirming our diagnosis of a left lower extremity DVT when we were unable to compress the vessel.

While focused bedside echocardiography is less sensitive for peripheral pulmonary embolism, its sensitivity for centrally located PEs or PEs which result in hemodynamic instability is very high.  Roughly 50% of patients with a PE will also have a DVT on US. Diagnosing a DVT early on at the bedside in a patient being evaluated for PE can enable earlier anticoagulation.

Key findings suggestive of PE on echo include

·      McConnell’s sign: RV wall hypokinesis is highly specific for PE (in comparison to other causes of RV strain such as pulmonary hypertension).  This is best seen on the apical four chamber view. There is akinesia of the free wall but normal motion at the apex.  

McConnell’s sign   

·      RV dilation: The ratio of RV to LV diameter is 0.6:1 measured at the base in the apical four chamber view (down close to the valves). Instead of taking a measurement, just eyeball this and make sure the RV doesn’t look bigger than the LV

·      D-sign: This finding is seen in the parasternal short view when the LV takes on the shape of the letter “D”. In cases of right heart strain, the pressures in the RV are elevated which causes the interventricular septum to flatten out appearing like a “D”. In the normal PSS view the LV looks like a doughnut and the RV looks like a crescent. 

D-Sign

Faculty Reviewer: Dr. Kristin Dwyer

 

Additional resources

http://rebelem.com/diagnosis-right-ventricular-strain-transthoracic-echocardiography/

http://blog.5minsono.com/rhs_1/

https://www.ncbi.nlm.nih.gov/pubmed/29174452