Management of glenohumeral synovitis secondary to influenza vaccination

Abstract

Glenohumeral synovitis is a rare complication of vaccination that can lead to shoulder dysfunction and prolonged pain. We report a case of florid glenohumeral synovitis after routine influenza vaccination, which we consider to have occurred because of the unintentional injection of antigenic material into synovial tissues, resulting in an immune-mediated inflammatory reaction. We provide a review of the literature for this condition and describe an invasive management approach, providing, for the first time, an arthroscopic evaluation and histopathological analysis.

Keywords: Adhesive capsulitis; bursitis; glenohumeral synovitis; shoulder; vaccination.

Figure 1.

A normal anteroposterior radiograph of the patient's left shoulder (5 weeks after vaccination).

Figure 2.

(a) A T1 magnetic resonance imaging (MRI) scan of the left shoulder, 7 weeks after vaccination. This demonstrates the subacromial and subdeltoid bursitis, which has been marked with the measurement tool. (b) A T2 MRI scan of the left shoulder, 7 weeks after vaccination. Here, the fluid-filled bursa appears white.

Figure 3.

(a) Glenohumeral synovitis of the rotator interval with a thickened middle glenohumeral ligament. (b) Villous synovitis in the subacromial space. (c) Signs of impingement in the subacromial space with synovitis visible in the background.