Ankylosing hyperostosis [Forestier], multiple sites in spine

This code represents diffuse idiopathic skeletal hyperostosis (DISH), also known as Forestier's disease, affecting multiple areas of the spinal column. It is characterized by ossification of ligaments and entheses, primarily in the spine, leading to stiffness and reduced range of motion. This non-inflammatory arthropathy involves the formation of flowing osteophytes along the anterolateral aspects of at least four contiguous vertebral bodies.

Assign this code when documentation clearly indicates a diagnosis of ankylosing hyperostosis (DISH) with involvement across several spinal segments. This diagnosis is typically made based on imaging findings (X-rays, CT scans) showing characteristic calcification and ossification patterns. Use this code when the physician explicitly states "Forestier's disease, multiple sites" or "diffuse idiopathic skeletal hyperostosis of the spine, multiple levels."

• Ensure documentation specifies "multiple sites" or "multiple levels" within the spine; otherwise, a more specific code for a single spinal region might be appropriate.
• Differentiate from ankylosing spondylitis (M45.-), which is an inflammatory condition with different diagnostic criteria and treatment. DISH does not involve sacroiliac joint fusion.
• Review imaging reports for confirmation of the characteristic flowing osteophytes and involvement of at least four contiguous vertebral bodies to support the diagnosis.