@lindamaegirl, I'd rather rely on bone markers.
You are right about Dexa numbers getting skewed by arthritis. But the skew often raises the scores of arthritic patients because it includes the calcium of osteophytes. Scores are lower in patients with RA because inflammatory arthritis does destroy bone.
REMS may turn out to be a better instrument, but I wish the company would pay out for the clinical trials and get recovery from insurance coverage rather than financing at the expense of osteoporosis patients.