A 17-year-old boy presented to the pediatric emergency department complaining of a right shoulder injury and right clavicular pain for two hours. The pain started after he checked another player into the boards while playing hockey. He had no head injury, loss of consciousness, or other trauma. He took 600 mg of ibuprofen with no relief, so he came to the ED.
He had no past medical or surgical problems, and reported his pain as 4/10 over the clavicle region. His review of system was otherwise negative. The patient's vitals were within normal limits. He had tenderness over the medial side of the right clavicle and no visible deformity or crepitus. He had intact distal neurovascularity over the right upper extremity and normal breath sounds bilaterally. All other systems were normal.
An x-ray of the right clavicle was negative for acute fracture. (Image 1.) The right clavicle appeared inferiorly displaced relative to the left. The patient was reevaluated, and was still complaining of pain despite receiving morphine. We ordered a CT without intravenous contrast of the sternoclavicular joint (SCJ), which revealed the diagnosis. (Images 2 and 3.)
Incidence of Dislocations
The cause of acute clavicular pain is mostly traumatic. It includes clavicle fracture, SCJ injury and dislocation, and mediastinal injuries. Sometimes muscles such as sternocleidomastoid and trapezium can be strained as well. Ligament injuries, although uncommon, can present after acute clavicle injury. Shoulder dislocation and acromioclavicular joint sprain can also cause acute clavicular pain.
Referred pain from a pneumothorax and acute coronary syndrome should also be considered for unresolved acute clavicular pain. Suspicion for post-traumatic medial clavicle was high for clavicle fracture and possible SCJ joint injury in this patient. His diagnosis was a right clavicle fracture and posterior dislocation of the sternoclavicular joint.
Sternoclavicular joint dislocations account for less than one percent of musculoskeletal fractures and dislocations. (Skeletal Radiol. 2016;45:1123.) Anterior dislocations are the most common and simple to treat. (Skeletal Radiol. 2016;45:1123; J Trauma Acute Care Surg. 2016;80:289.) Posterior dislocations are rare and can be life-threatening because they can cause injury to the lungs and mediastinum and compromise vascular structures with complications that can include pneumothorax, pneumomediastinum, thoracic outlet syndrome, tracheoesophageal fistula, esophageal rupture, venous thrombosis, spinal cord injury, and even death. (Pediatr Emerg Care. 2017;33:519.)
There is a 25-50 percent risk of injury to the mediastinum in posterior SCJ injuries with risk of hemorrhage and death. (Skeletal Radiol. 2016;45:1123.) Posterior SCJ injury is missed a quarter of the time on presentation. (Orthopedics. 2012;35:e108.) Twenty-five percent of posterior SCJ dislocations have been complicated by hemorrhage and death. (Orthopedics. 2012;35:e108; Am J Sports Med. 2014;42:2517.)
Possible fracture and mediastinal injury need to be considered with posterior SCJ dislocations. This diagnosis should also be considered in patients under age 25 because the medial clavicle epiphysis ossifies by 18 and may not fuse completely until 25-27. (Pediatr Emerg Care. 2017;33:519; J Pediatr Orthop. 2014;34:369; Eur Radiol. 1998;8:1116.)
SCJ injuries occur after indirect high-velocity trauma or a direct blow to the clavicle or from direct or indirect impact to the lateral aspect of the shoulder with force transmission medially, more commonly in skeletally immature patients. (J Trauma Acute Care Surg. 2016;80:289; J Pediatr Orthop. 2014;34:369.) A 20-year retrospective study that looked at SCJ injuries in level I trauma centers found that SCJ injuries were the most common in falls (32%), followed by sports (26%) and traffic injuries (13%). (J Trauma Acute Care Surg. 2016;80:289.)
Sports injury was the most common mechanism (76%). One study found that posterior SCJ dislocation and medial clavicular physeal fracture occur with equal prevalence and are missed with equal prevalence in patients under 25. (J Pediatr Orthop. 2014;34:369.)
Pain over the SCJ, localized swelling, and ecchymosis or reduced range of motion of the ipsilateral shoulder are universally reported. Vessel compression can be associated with burning and numbness. Symptoms of dysphagia and dyspnea can represent compression of the esophagus and trachea. (Am J Sports Med. 2014;42:2517.)
Given the significant risk for complications and possible death, it is important to coordinate with orthopedics and general surgery to manage fracture, displacement, and potential vascular injury involved in posterior SCJ injuries. (Orthopedics. 2012;35:e108.)
Radiographs are not always diagnostic, and AP views will not demonstrate posterior displacement and clavicle projections may have subtle or absent signs not clearly obvious on x-ray. (Pediatr Emerg Care. 2017;33:519.) A case study about a 15-year-old girl who presented with left shoulder pain after a blow to her shoulder in a basketball game had a normal x-ray, and a CT showed posterior SCJ dislocation but not fracture. An MRI confirmed medial clavicle physis fracture. CT is a good study, but consider an MRI if there is additional concern for further injury. (Skeletal Radiol. 2016;45:1123.)
Another case study used ultrasound to diagnose a posterior displacement of the medial clavicular metaphysis in a 19-year-old woman who presented after an initial ED visit two days earlier, during which she had a normal x-ray and was sent home with a sling. A CT on the second visit confirmed posterior displacement of the medial end of the left clavicle with a Salter-Harris type 1 facture and no injuries to mediastinal structures. (Pediatr Emerg Care. 2017;33:519.) Consider CT or MRI for a more definitive diagnosis of injury if there is high suspicion and radiographs are negative.
Treating patients with posterior SCJ injuries can be done with a closed reduction within 24 hours if there is no evidence of mediastinal compression or vessel injury. (J Pediatr Orthop. 2014;34:369.)
A meta-analysis of 140 patients showed similar success. (Am J Sports Med. 2014;42:2517.) Ninety-two percent of treatments with closed reduction and 95 percent with open reduction had similar outcomes defined as pain-free range of motion without recurrence. Closed reduction was successful if done in less than 48 hours. Final decisions are at the discretion of the orthopedic or vascular surgeon.
Our patient had an acute fracture involving the medial part of the right clavicle at the level of the clavicular head. The small clavicular head demonstrated comminuted fracture and was mildly displaced cephalad from the sternum when compared with the left clavicular head at the sternoclavicular joint. The lateral clavicular shaft fracture fragment was displaced more inferiorly and deep to the clavicular head and the sternum, located within the superior mediastinum, adjacent to the takeoff of the great vessels off the aortic arch.
CT angiography showed nodular contrast enhancement suspicious for possible venous extravasation at the brachiocephalic SVC junction without any convincing evidence for aortic injury. The trauma team was consulted, and the patient was taken to the operating room for open reduction internal fixation of the right clavicle and open reduction primary repair of the sternoclavicular joint dislocation.
The patient was discharged with a shoulder sling immobilizer and non-weight-bearing right upper extremity. He followed up with physical therapy and rehabilitation, and had complete recovery without any complications.