Nat. Rev. Rheumatol. 7, 654–663 (2011); doi:10.1038/nrrheum.2011.129

In the version of this article initially published, the authors omitted to cite the original research papers by Zhang, Y. et al. and Zhang, Q. et al. showing that doublecortin is expressed by articular chondrocytes (Biophys. Res. Commun. 363, 694–700 [2007 ]; Genesis 49, 75–82 [2011]). These two papers have now been included in the HTML and PDF versions of the review.