M46.91

Billable

Unspecified inflammatory spondylopathy, occipito-atlanto-axial region

HCC Category Mapping

V24HCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.307

ESRDHCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.000

What This Code Means

Inflammation of the spine in the upper neck region where the skull meets the spine that is not further specified.

Coding Tips

•This code applies to the occipito-atlanto-axial region (C0-C2 area); ensure documentation supports this specific anatomical location
•Distinguish from other cervical codes that apply to lower cervical regions

Clinical Significance

Unspecified inflammatory conditions of the occipito-atlanto-axial region require urgent evaluation due to proximity to vital neurological structures. Even when the specific inflammatory condition is unclear, the location demands careful monitoring and anti-inflammatory management.

Documentation Requirements

✓Occipito-atlanto-axial region involvement
✓Evidence of inflammatory process
✓Advanced cervical imaging findings
✓Neurological assessment and monitoring
✓Inflammatory laboratory markers
✓Response to anti-inflammatory therapy
✓Plans for diagnostic specification
✓Cervical stability assessment

Commonly Confused Codes

M46.51 — Infective spondylopathy same region when infectious M46.90 — Site unspecified when location is documented M48.02 — Cervical stenosis when structural rather than inflammatory M43.11 — Spondylolisthesis when instability is primary

Code Hierarchy

└M46Other inflammatory spondylopathies └M46.9Unspecified inflammatory spondylopathy └M46.91Unspecified inflammatory spondylopathy, occipito-atlanto-axial region

└M46.91Unspecified inflammatory spondylopathy, occipito-atlanto-axial region