Clinical Interventions in Aging (Sep 2012)
Changes in microarchitectural characteristics at the tibial epiphysis induced by collagen-induced rheumatoid arthritis over time
Abstract
Joo Hyung Lee,1 Keyoung Jin Chun,2 Han Sung Kim,3 Sang Ho Kim,4 Kwon-Yong Lee,1,6 Dae Jun Kim,5,6 Dohyung Lim,1,61Department of Mechanical Engineering, Sejong University, Seoul, Republic of Korea; 2Gerontechnology R & D Group, Korea Institute of Industrial Technology, Cheonan, Chungnam, Republic of Korea; 3Department of Biomedical Engineering, Yonsei University, Wonju, Gangwon, Republic of Korea; 4Department of Bioengineering and Department of Surgery, National University of Singapore, Singapore; 5Department of Advanced Material Engineering, 6Bioengineering Research Center, Sejong University, Seoul, Republic of KoreaBackground: Little is known about the time course of changes in the microarchitecture of the tibial epiphysis with rheumatoid arthritis (RA), although such information would be valuable in predicting risk of fracture. Therefore, we used in vivo microcomputed tomography (µ-CT) to assess patterns of microarchitectural alterations in the tibial epiphysis using collagen-induced RA in an animal model.Methods: Bovine type II collagen was injected intradermally into the tails of rats for induction of RA. The tibial joints were scanned by in vivo µ-CT at 0, 4, and 8 weeks following injection. Microarchitectural parameters were measured to evaluate alteration patterns of bone microarchitecture at the tibial epiphysis.Results: The microarchitectural alterations in an RA group were significantly different from those in a control group from 0 to 4 weeks and from 4 to 8 weeks following injection (P < 0.05). The distribution of trabecular bone thickness and trabecular bone separation from 0 weeks to 8 weeks differed significantly (P < 0.05).Conclusion: These results indicate that the patterns of microarchitectural alterations at the tibial epiphysis are strongly affected by collagen-induced progression of RA and entail a severe risk of fracture at the tibial epiphysis. This study represents a valuable first approach to tracking periodic and continuous changes in the microarchitectural characteristics of the tibial epiphysis with collagen-induced RA.Keywords: collagen-induced rheumatoid arthritis, in vivo microcomputed tomography, periodic microarchitecture alteration pattern, trabecular bone thickness, trabecular bone separation
