The support of the ultrasonography of the shoulder in the diagnosis of polymyalgia rheumatica with normal erythrocyte sedimentation rate

Abstract

Polymyalgia rheumatica (PMR) is a chronic inflammatory syndrome that affects the elderly population and whose diagnosis is mainly based on clinical criteria taking little advantage of the latest innovatory methods of diagnostic imaging, for instance ultrasonography. Although it is generally characterised by increasing of inflammation values as well as pain and stiffness on the shoulder and pelvic girdles, there is a significant percentage of patients with PMR whose erythrocyte sedimentation rate (ESR) is normal; in this case to make a diagnosis is difficult. The purpose of our study is to demonstrate how useful ultrasound investigations on the shoulders joints could be in order to make a diagnosis of PMR, especially for those patients with atypical normal ESR. Our case control study included 23 patients with atypical PMR and 88 patients with standard symptomatic PMR; both groups underwent shoulder ultrasound scans before receiving steroid therapy. As it has been previously shown, the ultrasound method is able to detect distinctive aspects in the joints and tissues of the patients with PMR; so that we could find that 90% of the patients with PMR of both groups suffered from bilateral subdeltoid bursitis. This disorder is seldom found in healthy people and consequently its presence could be considered a useful diagnostic test/check for/of PMR independently from ESR values.