M45
Non-billableAnkylosing spondylitis
Ankylosing spondylitis
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Inclusion Terms
Alternative clinical terms for this condition
- Rheumatoid arthritis of spine
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •arthropathic psoriasisL40.5
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •compartment syndrome (traumatic)A-)T79
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •Behçet's diseaseM35.2
Child Codes (11)
M45.0Ankylosing spondylitis of multiple sites in spine
M45.1Ankylosing spondylitis of occipito-atlanto-axial region
M45.2Ankylosing spondylitis of cervical region
M45.3Ankylosing spondylitis of cervicothoracic region
M45.4Ankylosing spondylitis of thoracic region
M45.5Ankylosing spondylitis of thoracolumbar region
M45.6Ankylosing spondylitis lumbar region
M45.7Ankylosing spondylitis of lumbosacral region
M45.8Ankylosing spondylitis sacral and sacrococcygeal region
M45.9Ankylosing spondylitis of unspecified sites in spine
M45.ANon-radiographic axial spondyloarthritis
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(51)
UMLS
- AS - Ankylosing spondylitisC0038013
- Ankylosing SpondylarthritidesC0038013
- Ankylosing SpondylarthritisC0038013
- Ankylosing SpondylitisC0038013
- Ankylosing SpondyloarthritidesC0038013
- Ankylosing SpondyloarthritisC0038013
- Ankylosing spondylitisC0038013
- Ankylosing spondylitis (disorder)C0038013
- Ankylosing spondylosisC0038013
- BECHTEREW DISC0038013
- BECHTEREWS DISC0038013
- Bechterew DiseaseC0038013
- Bechterew diseaseC0038013
- Bechterew's DiseaseC0038013
- Bechterew's diseaseC0038013
- Bechterews DiseaseC0038013
- Bekhterev's diseaseC0038013
- Idiopathic ankylosing spondylitisC0038013
- MARIE STRUEMPELL DISC0038013
- Marie Struempell DiseaseC0038013
- Marie Strümpell spondylitisC0038013
- Marie-Struempell DiseaseC0038013
- Marie-Struempell diseaseC0038013
- Marie-Strumpell spondylitisC0038013
- Rheumatoid SpondylitisC0038013
- Rheumatoid arthritis of spineC0038013
- Rheumatoid spondylitisC0038013
- SpAC0038013
- Spondylarthritides, AnkylosingC0038013
- Spondylarthritis AnkylopoieticaC0038013
- Spondylarthritis ankylopoieticaC0038013
- Spondylarthritis, AnkylosingC0038013
- Spondylitis AnkylopoieticaC0038013
- Spondylitis ankylopoieticaC0038013
- Spondylitis ankylosingC0038013
- Spondylitis, AnkylosingC0038013
- Spondylitis, RheumatoidC0038013
- Spondyloarthritides, AnkylosingC0038013
- Spondyloarthritis AnkylopoieticaC0038013
- Spondyloarthritis ankylopoieticaC0038013
- Spondyloarthritis, AnkylosingC0038013
- ankylosing spondylitisC0038013
- arthritis rheumatoid spineC0038013
- bechterew diseaseC0038013
- bechterew's diseaseC0038013
- marie strumpell diseaseC0038013
- marie-strumpell diseaseC0038013
- rheumatoid spondylitisC0038013
- spine rheumatoid arthritisC0038013
- spondylarthritis ankylopoieticaC0038013
- spondylitis ankylosingC0038013
Frequently Asked Questions
What is the ICD-10 code for ankylosing spondylitis?
The ICD-10-CM code for ankylosing spondylitis is M45. The full clinical description is "Ankylosing spondylitis". M45 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code M45 mean?
ICD-10-CM code M45 represents “Ankylosing spondylitis”. It is classified under Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue and is a non-billable header code. Use a more specific child code for billing purposes.
Is M45 a billable code?
No, M45 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 11 child codes under M45.
What chapter is M45 in?
M45 is in Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (codes M00-M99).
What codes cannot be used with M45?
M45 has Excludes1 notes indicating codes that cannot be used together with it, including: arthropathy in Reiter's disease (M02.3-); juvenile (ankylosing) spondylitis (M08.1).
What are the subcategories under M45?
M45 has 11 child codes, including: M45.0 (Ankylosing spondylitis of multiple sites in spine), M45.1 (Ankylosing spondylitis of occipito-atlanto-axial region), M45.2 (Ankylosing spondylitis of cervical region), M45.3 (Ankylosing spondylitis of cervicothoracic region), and 7 more.
What are the UMLS CUIs for M45?
M45 is linked to 1 UMLS Concept Unique Identifier: C0038013. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does M45 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like ankylosing spondylitis affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of M45?
M45 maps to the ICD-11 code: FA92.0Z (Axial spondyloarthritis, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.