Diffuse idiopathic skeletal hyperostosis

Diffuse idiopathic skeletal hyperostosis (DISH) is a condition characterized by abnormal calcification/bone formation (hyperostosis) of the soft tissues surrounding the joints of the spine, and also of the peripheral or appendicular skeleton. In the spine, there is bone formation along the anterior longitudinal ligament and sometimes the posterior longitudinal ligament, which may lead to partial or complete fusion of adjacent vertebrae. The facet and sacroiliac joints tend to be uninvolved. The thoracic spine is the most common level involved. In the peripheral skeleton, DISH manifests as a calcific enthesopathy, with pathologic bone formation at sites where ligaments and tendons attach to bone.

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