Acute brachial neuritis following influenza vaccination.

Brachial neuritis following vaccination is an uncommon but clinically important presentation of severe shoulder and arm pain associated with globally reduced range of movement. It may be confused with the more common diagnoses of rotator cuff pathology, adhesive capsulitis (frozen shoulder), shoulder arthritis or cervical spondylosis. We present a case of acute brachial neuritis, which posed a clinical diagnostic challenge to emergency, acute medical and rheumatology clinicians.