Alphabetic Index FY2027

M45

Ankylosing spondylitis

FY2027Chapter 13: Diseases of the musculoskeletal system and connective tissue/M45–M49 Spondylopathies

Non-billable headerNot valid on its own. Use one of the more specific codes under it.

M45 is a non-billable ICD-10-CM code category for ankylosing spondylitis. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are 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. Its coding notes include 2 Excludes1 entries and 11 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

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

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

This code
  • Behçet's disease (M35.2)
Also from chapter/block level (10 notes)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • 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)

Inclusion terms

Conditions classified to this code.

This code
  • Rheumatoid arthritis of spine

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 13 Diseases of the musculoskeletal system and connective tissue
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

More specific codes under M45 11