The Paradox of Bone Formation and Bone Loss in Ankylosing Spondylitis: Evolving New Concepts of Bone Formation and Future Trends in Management

  • Marina N. MagreyEmail author
  • Muhammad A. Khan
Spondyloarthritis (M Khan, Section Editor)
Part of the following topical collections:
  1. Topical Collection on Spondyloarthritis


Purpose of Review

The purpose of the study is to briefly review the molecular mechanisms that leads to structural damage in ankylosing spondylitis (AS), defined as new bone formation resulting in complete or incomplete ankylosis of the spine, and the impact of treatment with biologics to retard this process.

Recent Findings

The understanding of molecular mechanisms leading to new bone formation in AS has significantly improved but is still incomplete. Availability of biologics has greatly enhanced the treatment of patients with AS, but its impact on slowing the structural damage is still a matter of debate, although a few observational studies have shown that long term use of TNF-α blockers may slow radiographic progression. The availability of newer biologics targeting IL-17/1L23 has shown some promising results in slowing radiographic progression in AS.


Although the availability of TNF-inhibitors has greatly enhanced the treatment options for patients with AS, their impact on slowing the structural damage is still not clearly established. However, preliminary results using newer biologics targeting IL-17/1L23 axis are more encouraging but longer follow-up is needed.


Ankylosing spondylitis Axial spondyloarthritis Osteoproliferation Osteoporosis Bone morphogenetic proteins Wnt signaling pathways MicroRNAs TNF-α inhibitors Il-17 inhibitors Syndesmophytes New bone formation 



We would like to thank Dr. Irving Kushner, Dr. Stanley Ballou, and Dr. Maria Antonelli for reviewing the paper and making necessary edits.

Compliance With Ethical Standards

Conflict of Interest

Dr. Magrey reports personal fees from UCB PHARMA and personal fees from Jansenn, outside the submitted work.

Dr. Khan declares no conflicts of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Case Western Reserve University School of MedicineClevelandUSA
  2. 2.MetroHealth Medical CenterClevelandUSA
  3. 3.Division of RheumatologyCase Western Reserve University School of MedicineClevelandUSA

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