However, in contrast to ankylosing spondylitis, there is relative sparing of the sacroiliac joints and the absence of bamboo spine, annular ossification,
syndesmophyte, or erosion in ochronotic spine disease.
While relationship between ASDAS and
syndesmophyte formation is proven, the association with BASDAI is weaker.
Poddubnyy et al., "High level of functional dickkopf-1 predicts protection from
syndesmophyte formation in patients with ankylosing spondylitis," Annals of the Rheumatic Diseases, vol.
AS patients with no
syndesmophyte formation show significantly higher functional DKK-1 levels, suggesting that blunted Wnt signaling suppresses new bone formation and consequently
syndesmophyte growth and spinal ankylosis.
However, paradoxically, in PsA, patients may also display periarticular periostitis, and in AS and to a lesser extent PsA, prominent
syndesmophyte formation in the spine, leading to bridging ankylosis in its most severe form.
Imaging modalities other than radiographs and MRI should also be evaluated in the future, such as low-dose CT that shows promise for studies of
syndesmophyte development and growth (95).
Paravertebral ossifications in SAPHO may simulate
syndesmophyte in AS.
Regular use of NSAIDs has been shown to prevent
syndesmophyte formation.
These were identified as male sex, age, low body mass index (BMI), osteoporosis, disease duration, degree of
syndesmophyte formation, peripheral joint involvement, increased spinal motion restriction, and increased occiput-to-wall distance.
Among them, CRP is the most important because CRP levels in serum can predict persistent inflammation, subsequent
syndesmophyte formation, and treatment response to anti-TNF[alpha] drugs in AS patients [18,57-59].
Anteroposterior pelvis radiographs showed grade III bilateral sacroiliitis, and lateral lumbar radiographs revealed a decrease in lordosis, squaring of the vertebral bodies, and
syndesmophyte formation.
Anterior and posterior
syndesmophyte bridging with calcification of the spinal ligaments was observed on his thoracic spine radiographs.
