ICD-10-CM · Chapter 13 · M00-M99
M45 Ankylosing spondylitis
Includes
- Rheumatoid arthritis of spine
Excludes 1 (cannot be coded together)
- arthropathy in Reiter's disease (M02.3-)
- juvenile (ankylosing) spondylitis (M08.1)
Excludes 2 (not included here)
- Behçet's disease (M35.2)
Subcodes
Subcodes are listed below for reference. Detail pages are not available for chapters 11–22.
| Code | Description | Billable |
|---|---|---|
| M45..0 | Ankylosing spondylitis of multiple sites in spine | Yes |
| M45..1 | Ankylosing spondylitis of occipito-atlanto-axial region | Yes |
| M45..2 | Ankylosing spondylitis of cervical region | Yes |
| M45..3 | Ankylosing spondylitis of cervicothoracic region | Yes |
| M45..4 | Ankylosing spondylitis of thoracic region | Yes |
| M45..5 | Ankylosing spondylitis of thoracolumbar region | Yes |
| M45..6 | Ankylosing spondylitis lumbar region | Yes |
| M45..7 | Ankylosing spondylitis of lumbosacral region | Yes |
| M45..8 | Ankylosing spondylitis sacral and sacrococcygeal region | Yes |
| M45..9 | Ankylosing spondylitis of unspecified sites in spine | Yes |
| M45..A | Non-radiographic axial spondyloarthritis | No |
| M45..A0 | Non-radiographic axial spondyloarthritis of unspecified sites in spine | Yes |
| M45..A1 | Non-radiographic axial spondyloarthritis of occipito-atlanto-axial region | Yes |
| M45..A2 | Non-radiographic axial spondyloarthritis of cervical region | Yes |
| M45..A3 | Non-radiographic axial spondyloarthritis of cervicothoracic region | Yes |
| M45..A4 | Non-radiographic axial spondyloarthritis of thoracic region | Yes |
| M45..A5 | Non-radiographic axial spondyloarthritis of thoracolumbar region | Yes |
| M45..A6 | Non-radiographic axial spondyloarthritis of lumbar region | Yes |
| M45..A7 | Non-radiographic axial spondyloarthritis of lumbosacral region | Yes |
| M45..A8 | Non-radiographic axial spondyloarthritis of sacral and sacrococcygeal region | Yes |
| M45..AB | Non-radiographic axial spondyloarthritis of multiple sites in spine | Yes |
Plain-language term for this code
The following entry in the US Medical Glossary corresponds to ICD-10-CM category M45:
- Ankylosing Spondylitis — Espondilitis Anquilosante
Last reviewed: September 2026