Spondyloarthritis is a group of several related but phenotypically distinct chronic inflammatory diseases, characterized by progressive new bone formation which leads to ankylosis and functional disability. Radiographic images evidence not only erosive changes but also overgrowth of bony structures called syndesmophytes. These inflammation, bone destruction and new bone formation are located in the entheses, which constitutes the primary organ of the disease. As a consequence, the inflammatory process results in excess of bone formation and the impact depends on the location, cell type, cytokines and local microenvironment factors. Several molecules playing a role as immune modulators or regulators of bone homeostasis, mediate the imbalance between bone resorption and formation. In the same way, animal models suggest that joint ankylosis may be independent from the effects of tumor necrosis factor alpha. Therefore, the process of new tissue (bone) formation can be considered as an additional therapeutic target. The Wnt signaling pathway, which is considered the primary regulator of osteoblastogenesis, constitutes a new research field of great interest in the last decade.