M45.A0

Non-radiographic axial spondyloarthritis of unspecified sites in spine

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

BillableComplete code, valid to report

M45.A0 (also written M45A0) is a billable ICD-10-CM diagnosis code for non-radiographic axial spondyloarthritis of unspecified sites in spine. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 20 codes in category M45 (Ankylosing spondylitis). The Alphabetic Index lists it under 1 entry. Its coding notes include 2 Excludes1 entries and 11 Excludes2 entries.

Excludes1

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

Inherited from M45 Ankylosing spondylitis
  • 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.

Inherited from M45 Ankylosing spondylitis
  • 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)

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

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 1 entry