TNFSF11 and rheumatoid arthritis: In this sense, the RANKL/OPG relationship plays an essential role in regulating bone homeostasis in RA, and changes in this relationship may be a protective mechanism against accelerated bone loss in RA [47,51,52,53,55,56,57,58,59,60,61,62,63,64,65,66,67,68,69].