Background Through the clinical experience of the ultrasound examination of the shoulder lesions in untreated patients with polymyalgia rheumatica (PMR) and elderly-onset rheumatoid arthritis mimicking PMR (polymyalgic-EORA), we noted that there seems to be differences not in the kind or the frequency but in the degree of synovial inflammation between the two diseases.
Objectives To compare the severity of the shoulder syonvitis between PMR and polymyalgic-EORA using semi-quantitative ultrasound evaluation.
Methods We analyzed consecutive records of 14 PMR patients and 14 polymyalgic-EORA patients in our hospital between 2010 and 2012, in whom adequate grey-scale (GS) and power Doppler (PD) ultrasound images of both shoulders before treatment-start were available. The severity of tenosynovitis of the long-head of the biceps (LHB), bursitis of shoulder including subdeltoid, subacrominal and subcoracoid bursitis, and joint synovitis of grenohumeral joint (GHJ) were subjectively graded and scored for GS and PD on a four-point scale: 0 = absent, 1 = mild, 2 = moderate or 3 = severe.
Results There was a tendency that shoulder synovitis in PMR was milder than that in polymyalgic-EORA. There were statistically significant differences in the PD-grade of LHB, GS-grade of bursitis and GS-grade of GHJ by chi-square test. There was also a significant difference in GS-score of bursitis (1.18±1.28 vs 0.36±0.56, p=0.004), PD-score of bursitis (1.00±1.22 vs 0.36±0.73, p=0.021) and the sum of the 3 GS- and 3 PD-scores (6.43±5.45 vs 4.29±2.51, p=0.046) (mean ± SD, polymyalgic-EORA vs PMR) by Welch's t-test.
Conclusions Sonographic semi-quantitative assessment revealed that shoulder synovitis in PMR tends to be milder than that in elderly-onset RA mimicking PMR.
Disclosure of Interest None declared