To the Editor:
We appreciate Dr. Rothschild’s comments1 on our paper2. Regarding the diagnosis of rheumatoid arthritis (RA) of this patient, she met the 6 points of the 2010 American College of Rheumatology/European League Against Rheumatism classification criteria for RA (6 points and over are classified as definite RA, and she had joint involvement > 10 and abnormal acute-phase reactants)3. She did not have inflammatory back pain, which is characteristic of spondyloarthritis.
The computed tomography scan and the magnetic resonance imaging demonstrated calcification of the left alar ligament, and showed neither evidence of ossification of the posterior longitudinal ligament nor other abnormalities.
Dr. Rothschild’s comments that more than 20% of Teleoceras had spondyloarthritis (SpA), and that the alar ligament calcification may be caused by SpA and traumatic injuries4, are of great interest. The patient had no history of traumatic injury and therefore we could not obtain this information.