TNFSF11 and rheumatoid arthritis: The present study examined the effects of Bis (etidronate, alendronate and risedronate) alone and in combination therapy with statins on bone mineral density (BMD) and on four markers of bone metabolism, namely N-terminal telopeptide of type I collagen (NTX), tartrate-resistant acid phosphate-5b (TRACP-5b), C-terminal propeptide of type I procollagen (PICP) and RANKL in patients with RA.