Legg-Calvé-Perthes disease produces chronic hip synovitis and elevation of interleukin-6 in the synovial fluid.

Abstract

Legg-Calvé-Perthes disease (LCPD) is a childhood hip disorder of ischemic osteonecrosis of the femoral head. Hip joint synovitis is a common feature of LCPD, but the nature and pathophysiology of the synovitis remain unknown. The purpose of this study was to determine the chronicity of the synovitis and the inflammatory cytokines present in the synovial fluid at an active stage of LCPD. Serial MRI was performed on 28 patients. T2-weighted and gadolinium-enhanced MR images were used to assess synovial effusion and synovial enhancement (hyperemia) over time. A multiple-cytokine assay was used to determine the levels of 27 inflammatory cytokines and related factors present in the synovial fluid from 13 patients. MRI analysis showed fold increases of 5.0 ± 3.3 and 3.1 ± 2.1 in the synovial fluid volume in the affected hip compared to the unaffected hip at the initial and the last follow-up MRI, respectively. The mean duration between the initial and the last MRI was 17.7 ± 8.3 months. The volume of enhanced synovium on the contrast MRI was increased 16.5 ± 8.5 fold and 6.3 ± 5.6 fold in the affected hip compared to the unaffected hip at the initial MRI and the last follow-up MRI, respectively. In the synovial fluid of the affected hips, IL-6 protein levels were significantly increased (LCPD: 509 ± 519 pg/mL, non-LCPD: 19 ± 22 pg/mL; p = 0.0005) on the multi-cytokine assay. Interestingly, IL-1β and TNF-α levels were not elevated. In the active stage of LCPD, chronic hip synovitis and significant elevation of IL-6 are produced in the synovial fluid. Further studies are warranted to investigate the role of IL-6 on the pathophysiology of synovitis in LCPD and how it affects bone healing.

• Authors: Nobuhiro Kamiya, Ryosuke Yamaguchi, Naga Suresh Adapala, Elena Chen, David Neal, Obrien Jack, Alec Thoveson, Paul Gudmundsson, Case Brabham, Olumide Aruwajoye, Hicham Drissi, Harry K W Kim
• Journal: Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research (J Bone Miner Res) Vol. 30 Issue 6 Pg. 1009-13 (Jun 2015) ISSN: 1523-4681 [Electronic] United States
• PMID: 25556551 (Publication Type: Clinical Trial, Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 American Society for Bone and Mineral Research.

Chemical References

• IL1B protein, human
• IL6 protein, human
• Interleukin-1beta
• Interleukin-6
• Tumor Necrosis Factor-alpha

Topics

• Female
• Hip Joint (diagnostic imaging, metabolism)
• Humans
• Interleukin-1beta (metabolism)
• Interleukin-6 (metabolism)
• Legg-Calve-Perthes Disease (diagnostic imaging, metabolism)
• Male
• Radiography
• Synovial Fluid (metabolism)
• Synovitis (diagnostic imaging, metabolism)
• Tumor Necrosis Factor-alpha (metabolism)