M45Header code — not billable
Ankylosing spondylitis
- Chapter
- 13. Diseases of the musculoskeletal system and connective tissue
- Category
- M45
- Effective date
- October 1, 2026
Related codes in category M45
M45.0Ankylosing spondylitis of multiple sites in spineYesM45.1Ankylosing spondylitis of occipito-atlanto-axial regionYesM45.2Ankylosing spondylitis of cervical regionYesM45.3Ankylosing spondylitis of cervicothoracic regionYesM45.4Ankylosing spondylitis of thoracic regionYesM45.5Ankylosing spondylitis of thoracolumbar regionYesM45.6Ankylosing spondylitis lumbar regionYesM45.7Ankylosing spondylitis of lumbosacral regionYesM45.8Ankylosing spondylitis sacral and sacrococcygeal regionYesM45.9Ankylosing spondylitis of unspecified sites in spineYesM45.ANon-radiographic axial spondyloarthritisM45.A0Non-radiographic axial spondyloarthritis unsp site in spinYes
Frequently asked questions
What is ICD-10 code M45?
M45 is an ICD-10-CM diagnosis code for Ankylosing spondylitis.
Is M45 a billable code?
No. M45 is a category/header code, not billable on its own — use one of its more specific child codes instead.
What ICD-10-CM chapter is M45 in?
M45 falls under Chapter 13: Diseases of the musculoskeletal system and connective tissue.
When did M45 become effective?
M45 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.
What other codes are related to M45?
M45 belongs to category M45, which includes 12 other codes — see the related codes list on this page.
ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.