@article {Geusens1856, author = {P Geusens and D Vosse and D van der Heijde and J Vanhoof and A van Tubergen and J Raus and S van der Linden}, title = {High prevalence of thoracic vertebral deformities and discal wedging in ankylosing spondylitis patients with hyperkyphosis.}, volume = {28}, number = {8}, pages = {1856--1861}, year = {2001}, publisher = {The Journal of Rheumatology}, abstract = {OBJECTIVE: To study the prevalence of deformities of vertebrae and intervertebral discs in patients with ankylosing spondylitis (AS) in relation to fixed hyperkyphosis of the spine. METHODS: Altogether 50 patients (15 women, 35 men) with AS were studied. Hyperkyphosis was measured by the occiput to wall distance (OWD). Anterior (Ha), mid- (Hm), and posterior height (Hp) of the vertebrae and intervertebral discs were measured on lateral radiographs of the thoracic (Th5-Th12) and lumbar spine (L1-L5). Vertebral shapes were analyzed according to McCloskey, et al. Wedging of discs was calculated as Ha/Hp. Hyperkyphosis was defined as OWD \> 1 cm. RESULTS: In the thoracic spine, the prevalence of vertebral deformities was higher in patients with hyperkyphosis (n = 38) compared to patients without hyperkyphosis (n = 12) (45\% vs 8\%; p = 0.01). The prevalence of thoracic vertebral deformities in patients with hyperkyphosis differed little between men and women (39\% vs 58\%; p \> 0.10) and among patients above and below the age of 45 years (50\% vs 33\%; p \> 0.10). Patients with one or more deformed thoracic vertebrae had a higher mean OWD than patients without deformed vertebrae (12 +/- 7 vs 7 +/- 6 cm; p \< 0.01). The total sum of deformities of the thoracic vertebrae and discs explained 43\% of the variance of the age adjusted OWD (p \< 0.001). Deformities of lumbar vertebrae and discs did not contribute to hyperkyphosis. CONCLUSION: In patients with AS and hyperkyphosis, deformities of the thoracic vertebrae occur frequently and, together with wedging of the thoracic discs, contribute significantly to fixed hyperkyphosis of the spine.}, issn = {0315-162X}, URL = {https://www.jrheum.org/content/28/8/1856}, eprint = {https://www.jrheum.org/content/28/8/1856.full.pdf}, journal = {The Journal of Rheumatology} }