The sternoclavicular joint is composed of the proximal
end of the clavicle and the manubrium of the sternum. Sternoclavicular joint
injuries are uncommon shoulder injuries. In young patients, the injury is usually
a physeal injury. Medial clavicle physeal fracture occurs in a patient less
than 25 years old. Th epiphysis ossifies at the age of 18 and closes between
20-25 years of age. Anterior dislocation is more common than posterior
dislocation. The AP x-ray is difficult to interpret, and we get what is called
the Serendipity view X-ray, which is 40° cephalic tilt view with the beam
focused on the manubrium, then you compare both clavicles. The serendipity view
allows for identification of the anterior or posterior translation. In practice
clinically, the anterior dislocation will be obvious. The posterior dislocation
will not be obvious. The patient will have pain, order a CT scan. A CT scan is
the best study to evaluate acute, traumatic injuries of the sternoclavicular
joint. It will help determine what type of injury or dislocation (anterior or
posterior). A Ct scan will show if the injury is a physeal injury or if it is a
true dislocation. It shows the status of the mediastinal structures. Anterior
dislocation is common. The patient will have pain, a bump, or swelling that is
increased by abduction of the arm. Anterior dislocation is unstable if you
reduce it, but it is benign. If it is acute, try to reduce it, otherwise accept
the deformity. Observe the patient and treat the patient symptomatically. The
anterior sternoclavicular dislocation is rarely symptomatic when left
unreduced. Most of the time the patient will do very well, and it will not
affect function or range of motion (resuming of unrestricted activity in 3
months). If the injury is chronic and symptomatic, then you will do surgery.
The type of surgery that is done is a resection of the medial part of the
clavicle. Resect less than 15 mm of the medical clavicle. Do soft tissue
stabilization of the residual medial clavicle with costoclavicular ligament
reconstruction. Reconstruction of the sternoclavicular joint utilizing tendon
graft (allograft or autograft can be used). The hamstring tendon technique is popular,
and the figure eight technique is commonly used because it provides great
stability. The posterior sternoclavicular dislocation is less common and is a
true orthopaedic emergency. 1/3 of the posterior dislocations may have
compressive effect by exhibiting pressure on the great vessels, esophagus of
the trachea. It may cause dyspnea, tachypnea, dysphagia, or paresthesia and it
needs reduction. It has minimal, visible clinical findings. Sometimes the
affected shoulder is shortened with forward thrust. The posterior
sternoclavicular dislocation will be stable after reduction. You will have
general anesthesia with thoracic surgeon backup. With a posterior
sternoclavicular dislocation start with closed reduction with the hand or with
a towel clip and lift the clavicle up. When you do closed reduction, the
initial position for the extremity is the same for anterior and posterior
dislocation. You will have general anesthesia and you will do abduction and
extension of the shoulder. For the posterior dislocation, you will do abduction
and extension. There will be a bump underneath the medial scapula. You will
manipulate the medial clavicle with a towel clamp or with the fingers, lifting
the clavicle up and reducing the joint. The posterior dislocation is usually
stable, so give the patient a sling for 3-4 weeks. For the anterior
dislocation, you will do direct pressure. If the reduction is stable, you will
use a figure 8 strap or sling, and do therapy at 3-4 weeks. If posterior
dislocation is unstable or irreducible, you will do reduction or excision of
the medial clavicle plus stabilization of the soft tissue. If it is chronic,
recurrent, or symptomatic, you will do excision of the medial clavicle plus
soft tissue stabilization. Do not try to do closed reduction in late or chronic
cases, because there are mediastinal adhesions that may cause problems inside
the chest.
