Better Quantification of Syndesmophyte Growth in Axial Spondyloarthritis
Purpose of review
We review new insights to syndesmophyte growth in axial spondyloarthritis revealed by computed tomography (CT).
CT allows full reliable quantitation of syndesmophytes. About 70% of patients had detectable growth in syndesmophyte volume or height in 1 year. Syndesmophyte growth is not uniform, but can be highly heterogeneous even within the same disc space of the same patient. Syndesmophytes are not randomly distributed around the vertebral rim but have preferred locations (posterolateral and anterolateral) which vary along the spine. The frequency of syndesmophyte involvement also varies along the spine. It is highest at the thoracolumbar junction and higher in the thoracic than lumbar spine.
CT syndesmophyte quantitation is a promising tool for studies of medications or biomarkers and their relations with syndesmophyte progression. The localization and growth patterns of syndesmophytes suggest importance for local factors such as mechanical stress.
KeywordsAxial spondyloarthritis Ankylosing spondylitis Computed tomography Syndesmophytes
This work was supported by the Intramural Research Program, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health.
Compliance with Ethical Standards
Conflict of Interest
The authors declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
Written informed consent was obtained for all our studies under IRB-approved protocols.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
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