Dr John Mackenzie MBChB , Dip MSM, FACEM . Staff Specialist Emergency Medicine, Consultant Hyperbaric Medicine Specialist, at Prince of Wales Hospital. Known for cycling endlessly for no apparent reason. 20 years of developing virtual learning for clinicians at all levels.
Dr James Miers
Dr James Miers BSc BMBS (Hons) FACEM, Staff Specialist in Emergency Medicine, Prince of Wales Hospital, Sydney. Passion for gypsy jazz and chess. Lead author of Lead author of Emergency Procedures App.
Acromioclavicular joint (AC) injuries are associated with damage to the joint and surrounding structures.
The acromioclavicular joint, together with the sternoclavicular joint, connects the upper limb to the skeleton.
The support of the acromioclavicular joint is provided by the ligament and muscle surrounding the joint. The capsule surrounding the acromioclavicular joint is strengthened by the acromioclavicular ligaments. The joints are acromioclavicular ligaments that provide horizontal stability.
The coracoclavicular ligaments consist of two parts, the lateral trapezoid, and the medial conoid, and connect the distal lower clavicle to the coracoid process of the scapula. The coracoclavicular ligament is the main stabilizing ligament of the upper limb.
Acromioclavicular joint injuries occur at all ages, but are most common in the 20-40 year age group, 5x times more common in men than women. It is a common contact sports injury in young male athletes (1).
There are two main mechanisms of acromioclavicular joint injury; direct and indirect (2). A direct blow or fall to the shoulder results in a superior force on the acromion with restricted clavicular movement in the joint, the acromion is forcibly pushed down and medially relative to the clavicle. It can occur indirectly as a result of a fall on the hand or elbow, causing the humerus to be pushed into the acromion, resulting in lower-grade injuries that typically protect the coracoclavicular ligament.
Imaging can be used to classify acromioclavicular injuries and is the most widely used Rockwood classification.
References and Further Reading
Dyan V. Flores, Paola Kuenzer Goes, Catalina Mejía Gómez et-al. Imaging of the Acromioclavicular Joint: Anatomy, Function, Pathologic Features, and Treatment. (2020) RadioGraphics. 40 (5): 1355-1382.
Vanhoenacker F, Maas M, Gielen JL. Imaging of Orthopedic Sports Injuries. (2006)
Tintinalli’s Emergency Medicine, A Comprehensive Study Guide 9th edition. ( 2019)
A 35-year-old male presented to fast track complaining of bilateral severe shoulder pain for one-day duration. He reports waking up like that, and not being able to move his shoulders much due to the pain.
He denied any recent falls, injuries, or direct trauma to his shoulders. He also denied any fever, rashes, skin changes, headaches, numbness or weakness. No further findings found upon review of systems. Past medical history revealed a history of epilepsy. Otherwise, he’s not on any medications and denies any known allergies.
Physical examination showed slim male, with flattened anterior shoulders and normal inspection of the skin overlying his shoulders. He had internally rotated upper extremities, flexed elbows, and arms held in adduction. Upon attempts on any passive or active test of the range of motion, he experienced reluctance and pain on external rotation or abduction of his shoulders. Bilateral Shoulder X-rays were obtained.
You need to evaluate each case separately. The cases like this patient, with associated fractures, can complicate your management, and hence consulting orthopedic services would be advised, as surgical interventions should be evaluated.
If closed reduction fails, usually open reduction is pondered by subspecialty, especially in cases with extensive damage to the humeral head.
In cases with no associated fractures, the approach is the reduction of the dislocation. Most of them would require procedural sedation and analgesia.
Consider discussing options of procedural sedation and analgesia, with or without intraarticular blocks with your attending, for better and successful procedures, and minimal pain for your patient. The most convenient procedure options should also be discussed with patients, and consent should be taken.
Patients would require pre and post-reduction neurovascular examination and X-rays.
Make sure your patient is examined again after the procedure, assessing the stability of the joint for regained full range of motion.
Shoulder immobilization and follow up care plans with orthopedics services should be arranged.
Don’t forget, patients with known epilepsy, non-adherence or uncontrolled seizures have to be evaluated as well, and referred to appropriate neurology evaluation.
Bilateral shoulder dislocations are rare and of these, bilateral posterior shoulder dislocations are more prevalent than bilateral anterior shoulder dislocations.
Bilateral fracture-dislocation is even rarer, with a few cases reported in the literature.
In the rare case of an asymmetrical bilateral dislocation, attention may be distracted to the more evident lesion, which is the anterior dislocation. This may lead to delayed diagnosis, especially in an unconscious patient in a post-ictal state.
In the present case, open reduction and internal fixation was performed.
References and Further Reading
Roberts & Hedges Clinical Procedures in Emergency Medicine (6th ed) 2014. Philadelphia. Elsevier Saunders Inc. – Chapter 49
Tintinalli’s Emergency Medicine: A Comprehensive Study Guide (7th ed) 2011. New York. McGraw Hill Companies Inc. – Chapter 268
Rosen’s Emergency Medicine: Concepts and Clinical Practice (8th ed) 2014. Philadelphia. Elsevier Saunders Inc. – Chapter 53
Sharma A, Jindal S, Narula MS, Garg S, Sethi A. Bilateral Asymmetrical Fracture Dislocation of Shoulder with Rare Combination of Injuries after Epileptic Seizure: A Case Report. Malays Orthop J. 2017;11(1):74–76. doi:10.5704/MOJ.1703.011 – https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5393121/
Credit and acknowledgment for Dr. Eelaf Elhassan for sharing the case.