Ultrasonography of the glenohumeral joints - a helpful instrument in differentiation in elderly onset rheumatoid arthritis and polymyalgia rheumatica

In a prospective study, the glenohumeral joints of 51 patients (aged 60 or above) were examined, using ultrasonography. Twenty-two patients were suffe ring from characteristic polymyalgia rheumatica (PMR) symptoms. In contrast , 29 other patients initially had similar complaints, but were diagnosed as having elderly onset rheumatoid arthritis (EORA, rheumatoid factor negativ e) upon development Of typical symptoms. Ultrasound examination revealed gl enohumeral joint inflammation in 40.9% (9/22) of the patients with PMR and 65.5% (19/29) of the patients with EORA. A discrete symmetrical biceps tend on sheath effusion was found in only three patients and unilateral in six p atients with PMR. In contrast, 12 patients with EORA presented a massive ef fusion of the bleeps tendon sheath, in some cases combined with a bilateral subdeltoid bursitis, and an intraarticular (i.a,) effusion/synovitis. To s ummarize our results: an i.a. effusion/synovitis, subdeltoid bursitis and b iceps tendon sheath effusion were Inore frequent in patients with EORA. wit h a predominate symmetry and signs for massive inflammation. The typical ul trasonographic result in patients with PMR was a unilateral inflammation of the glenohumeral joint with predominate discrete biceps tendon sheath effu sion and, in comparison with the EORA group, with signs of a low grade infl ammation. We conclude that the results of our prospective study might be he lpful in the differentiation of PMR and a rheumatoid factor negative subgro up of EORA at the first time of manifestation where clinical overlaps can b e observed. However, ultrasonography of the glenohumeral joints might be a good and helpful instrument of differentiation in both diseases.