Ankylosing hyperostosis, sacral and sacrococcygeal region

This code represents a non-inflammatory ossification of ligaments and entheses, specifically affecting the sacral and sacrococcygeal regions. It is characterized by the formation of new bone, often bridging vertebral bodies, without significant involvement of the sacroiliac joints or apophyseal joints, distinguishing it from ankylosing spondylitis.

Use this code for patients diagnosed with diffuse idiopathic skeletal hyperostosis (DISH) where the primary or most significant manifestation is in the sacral or sacrococcygeal spine. Documentation should clearly indicate the presence of hyperostosis or ossification in these specific spinal segments, often identified through imaging studies like X-rays or CT scans.

• Differentiate from ankylosing spondylitis (M45.-) which involves inflammatory changes and sacroiliac joint fusion.
• Ensure documentation specifies the sacral and sacrococcygeal region; other spinal regions of DISH have different codes.
• This code is typically a primary diagnosis when the sacral/sacrococcygeal involvement is the reason for the encounter or the most significant finding.