Bone Proliferation in Ankylosing Tarsitis Might Involve Mechanical Stress, and Hormonal and Growth Factors

To the Editor: We thank The Journal for the opportunity to address some details in the editorial by Appel and Sieper1 about our recent paper “Bone Lineage Proteins in the Entheses of the Midfoot in Patients with Spondyloarthritis”2. As Appel and Sieper stated1, we reported the lack of inflammatory lesions in our set of tissue samples2. Yet in contrast to their interpretation, our findings did not result from the study of patients in the advanced...