Erratum to: Curr Rheumatol Rep (2012) 14:409–414

DOI 10.1007/s11926-012-0274-2

The original version of this article, published in Current Rheumatology Reports, Volume 14, Issue 5, October 2012, inadvertently omitted the word “or” from both the left and the right panels of Fig. 2. The figure provided is now correct.

figure a