Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Diffuse idiopathic skeletal hyperostosis ?
    ### Response:
    Diffuse idiopathic skeletal hyperostosis (DISH) is a form of degenerative arthritis in which the ligaments (connective tissues that connect bones) around the spine turn into bone. Many people with this condition do not experience any symptoms. When present, the most common features are pain and stiffness of the upper back; however, other symptoms may also develop when bone spurs press on nearby organs or parts of the body.
    