Degenerative changes of the thoracic spine do exist in patients with diffuse idiopathic skeletal hyperostosis: a detailed thoracic spine CT analysis

BackgroundDegenerative intervertebral disease (DID) is an exclusion criterion in the Resnick and Niwayama radiographic classification for diffuse idiopathic skeletal hyperostosis (DISH). However, although DID was previously described in DISH, no systematic computed tomography (CT) analysis has been reported so far.PurposeTo assess for the presence and prevalence of such changes on CT examinations of the thoracic spine of individuals with DISH.Material and MethodsIntervertebral space (D1–L1) on chest CT examinations of DISH patients was retrospectively evaluated for the presence of DID. Parameters evaluated were disc space height, disc protrusion, subchondral cysts/sclerosis, Schmorl nodes, vacuum phenomenon, and posterior elements including costovertebral and facet joints. Parameters were compared with two age- and gender-matched control groups of individuals whose entire spine CT lacked evidence of DISH (Control 1 individuals < 2 flowing osteophytes, Control 2 individuals < 4 and ≥ 2 flowing osteophytes)...