Tendon

Surgery

Rheumatology

Environmental health

Ankylosing spondylitis

Enthesis

Population

Internal medicine

Hormone

Growth hormone

Medicine

The Journal of Rheumatology

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 stage of what we have called “ankylosing tarsitis”, but for reasons that were already mentioned in the paper. Figure 1 does not represent the population included in the study; it illustrates only the most advanced stage of ankylosing tarsitis2. In fact, there were only 3 … Address correspondence to Dr. R. Burgos-Vargas, Rheumatology Department, Hospital General de México, Dr. Balmis 148, México DF 06720, México. E-mail: r.burgos.vargas{at}gmail.com

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