M45

Non-billable

Ankylosing spondylitis

Ankylosing spondylitis

This is a header/category code. For billing purposes, use a more specific child code from the list below.

Status

Non-billable / Header

Block

M45-M49

Child Codes

11

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)

  • arthropathy in Reiter's disease (M02.3-)
  • juvenile (ankylosing) spondylitis (M08.1)

Excludes 2

Conditions not included here, but the patient may have both

  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • Behçet's disease (M35.2)

Child Codes (11)

Also Known As / Clinical Terms

UMLS

Frequently Asked Questions

What is ICD-10 code M45?

ICD-10-CM code M45 represents "Ankylosing spondylitis". It 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.

Automate ICD-10 Coding With AI

Send clinical text to the AutoICD API and get back structured ICD-10 codes with confidence scores. Integrates into any EHR or billing system in minutes.

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.