Interleukin-1-induced glenohumeral synovitis and shoulder pain in rotator cuff diseases

• Published in: Journal of orthopaedic research Vol. 20; no. 6; pp. 1365 - 1371
• Main Authors: Gotoh, Masafumi, Hamada, Kazutoshi, Yamakawa, Hideyuki, Yanagisawa, Kazuhiro, Nakamura, Masato, Yamazaki, Hitoshi, Inoue, Akio, Fukuda, Hiroaki
• Format: Journal Article
• Language: English
• Published: Hoboken Elsevier Ltd 01.11.2002; Wiley Subscription Services, Inc., A Wiley Company; Blackwell Publishing Ltd
• Subjects: Adult; Aged; Female; Gene Expression; Humans; Interleukin-1 - genetics; Male; Middle Aged; Pain - immunology; Pain - pathology; Pain - physiopathology; RNA, Messenger - analysis; Rotator Cuff - immunology; Rotator Cuff - pathology; Rotator Cuff - physiopathology; Shoulder Joint - immunology; Shoulder Joint - pathology; Shoulder Joint - physiopathology; Synovitis - immunology; Synovitis - pathology; Synovitis - physiopathology
• ISSN: 0736-0266; 1554-527X
• DOI: 10.1016/S0736-0266(02)00063-3

Synovitis of the subacromial bursa has been identified as a main source of shoulder pain in rotator cuff diseases. Little interest, however, has been paid into the synovitis of glenohumeral joint. The mRNA expression levels of interleukin-1β (IL-1β) and interleukin-1 receptor antagonists produced in the synovitis reflect the magnitude of inflammation. The present study was undertaken to determine the relationship between mRNA expression levels of IL-1β and its receptor antagonists (secreted interleukin-1 receptor antagonist (IL-1ra) and intracellular IL-1ra) in the synovium of the glenohumeral joint and shoulder pain in rotator cuff diseases, analyzing the synovial specimens by reverse transcriptase polymerase chain reaction. Thirty-five patients with rotator cuff diseases were candidates. Based on the presence of cuff perforation, they were divided into two categories: 16 with non-perforating tears and 19 with perforating tears. The degree of shoulder pain was evaluated by use of a visual analogue scale. The pain degree of non-perforating tears was significantly greater than that of perforating tears ( P<0.01). In contrast, the expression levels of the cytokine-mRNAs were constitutively greater in perforating tears than in non-perforating tears ( P<0.01, respectively). The expression levels of the cytokine-mRNAs were inversely correlated with the degree of pain (IL-1β: r=0.930; secreted IL-1ra: r=0.861; intracellular IL-1ra: r=0.932, P<0.001 respectively). These results suggest that the expression levels of the cytokine-mRNAs in the synovium of the glenohumeral joint contribute less to the generation of shoulder pain in rotator cuff diseases.