Injection Technique for Sternalis Syndrome

Indications and Clinical Considerations

Sternalis syndrome is a constellation of symptoms consisting of midline anterior chest wall pain that can radiate to the retrosternal area and the medial aspect of the arm ( Fig. 111.1 ). Sternalis syndrome can mimic the pain of myocardial infarction and is frequently misdiagnosed as such. Sternalis syndrome is a myofascial pain syndrome characterized by trigger points in the midsternal area. In contradistinction to costosternal syndrome, the pain of sternalis syndrome is not exacerbated by movement of the chest wall and shoulder.

Physical examination reveals myofascial trigger points at the midline over the sternum. Occasionally, there is a coexistent trigger point in the pectoralis muscle or sternal head of the sternocleidomastoid muscle. Pain is reproduced with palpation of these trigger points rather than movement of the chest wall and shoulders. A positive “jump sign” is present when these trigger points are stimulated. Trigger points at the lateral border of the scapula may also be present and amenable to injection therapy.

Plain radiographs are indicated for all patients with suspected sternalis syndrome to rule out occult bony disease, including metastatic lesions. On the basis of the patient’s clinical presentation, additional testing may be indicated, including complete blood cell count, prostate-specific antigen, sedimentation rate, and antinuclear antibody testing. Computed tomography and magnetic resonance imaging of the chest are indicated if a retrosternal mass such as a thymoma is suspected and to identify other causes of the patient’s pain symptomatology ( Fig. 111.2 ). Electromyography is indicated in patients with sternalis syndrome to help rule out cervical radiculopathy or plexopathy, which may be considered because of the referred arm pain. The injection technique presented later serves as both a diagnostic and a therapeutic maneuver.