With the advent of seat belts that cross the chest, sternoclavicular syndrome is being seen with greater frequency by clinicians. The joint is often traumatized during acceleration/deceleration injuries and blunt trauma to the chest.
With severe trauma, the joint may sublux or dislocate in association with fractures of adjacent structures. Overuse or misuse also can result in acute inflammation of the sternoclavicular joint, which can be debilitating.
Because the sternoclavicular joint is a true joint, it is susceptible to the development of arthritis, including osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, Reiter syndrome, infection, and psoriatic arthritis.
The joint also is subject to invasion by tumor from either primary malignancies, including thymoma, or metastatic disease.
Pain emanating from the sternoclavicular joint often mimics the pain of cardiac origin.
What are the Symptoms of Sternoclavicular Syndrome
On physical examination, obvious physical deformity may be present and the patient vigorously attempts to splint the joint by keeping the shoulders stiffly in neutral position. Pain is reproduced with active protraction or retraction of the shoulder and full elevation of the arm.
Shrugging of the shoulder also may reproduce the pain. The sternoclavicular joint may be tender to palpation and feel hot and swollen if acutely inflamed. The patient also may report a clicking sensation with movement of the joint.
How is Sternoclavicular Syndrome diagnosed?
Plain radiographs are indicated in all patients who have pain thought to emanate from the sternoclavicular joint to rule out occult bony pathological processes, including tumor.
Based on the patient’s clinical presentation, additional tests, including complete blood cell count, prostate-specific antigen level, erythrocyte sedimentation rate, and antinuclear antibody testing, may be indicated.
Computed tomography (CT), ultrasound imaging, and magnetic resonance imaging (MRI) of the joint is indicated if joint instability, tumor, or infection is suspected and to clarify the diagnosis.
Injection of the sternoclavicular joint with a local anesthetic, steroid, or both serves as a diagnostic and therapeutic maneuver.
As mentioned earlier, the pain of sternoclavicular syndrome is often mistaken for pain of cardiac origin and can lead to visits to the emergency department and unnecessary cardiac workups.
If trauma has occurred, sternoclavicular syndrome may coexist with fractured ribs or fractures of the sternum itself, which can be missed on plain radiographs and may require radionucleotide bone scanning for proper identification.
Tietze syndrome, which is painful enlargement of the upper costochondral cartilage associated with viral infections, can be confused with sternoclavicular syndrome.
Neuropathic pain involving the chest wall also may be confused or coexist with sternoclavicular syndrome. Examples of such neuropathic pain include diabetic polyneuropathies and acute herpes zoster involving the thoracic nerves.
The possibility of diseases of the structures of the mediastinum is ever present and these diseases sometimes can be difficult to diagnose. Pathological processes that inflame the pleura, such as pulmonary embolus, infection, and Bornholm disease, also should be considered.
Initial treatment of the pain and functional disability associated with sternoclavicular syndrome should include a combination of nonsteroidal antiinflammatory drugs (NSAIDs) or cyclooxygenase-2 (COX-2) inhibitors. Local application of heat and cold also may be beneficial. The use of an elastic clavicle splint may help provide symptomatic relief and help protect the sternoclavicular joints from additional trauma.
For patients who do not respond to these treatment modalities, injection of the sternoclavicular joint using a local anesthetic and steroid may be a reasonable next step. Ultrasound guidance may improve the accuracy of needle placement and decrease the incidence of needle-related complications.
Because of the many pathological processes that may mimic the pain of sternoclavicular syndrome, the clinician must be careful to rule out underlying cardiac disease and diseases of the lung and structures of the mediastinum.
Failure to do so could lead to disastrous results. The major complication of this injection technique is pneumothorax if the needle is placed too laterally or deeply and invades the pleural space. Infection, although rare, can occur if strict aseptic technique is not followed. The possibility of trauma to the contents of the mediastinum remains an ever-present possibility. This complication can be greatly decreased if the clinician pays close attention to accurate needle placement.
Patients with pain emanating from the sternoclavicular joint often attribute their pain symptoms to a heart attack. Reassurance is required, although it should be remembered that this musculoskeletal pain syndrome and coronary artery disease can coexist.
Tietze syndrome, which is painful enlargement of the upper costochondral cartilage associated with viral infections, can be confused with sternoclavicular syndrome, although both respond to the injection technique described.
The use of physical modalities, including local heat and gentle range-of-motion exercises, should be introduced several days after the patient undergoes this injection technique for sternoclavicular joint pain.
Vigorous exercises should be avoided because they would exacerbate the patient’s symptoms. Simple analgesics and NSAIDs may be used concurrently with this injection technique. Laboratory evaluation for collagen-vascular disease is indicated in patients with sternoclavicular joint pain in whom other joints are involved.