M46.81 Other specified inflammatory spondylopathies, occipito-atlanto-axial region

Billable ICD-10-CM code, FY2026.

Risk adjustment (HCC)

• CMS-HCC V22: HCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease
• ESRD V24: HCC 40

MS-DRG index

Defines the logic of DRG(s) 551-552 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 720.89 Other inflammatory spondylopathies (approximate)

Code annotations containing back-references to M46.81

Back-references to M46

• Type 1 Excludes: G55 Nerve root and plexus compressions in diseases classified elsewhere ("nerve root compression (due to) (in) spondylopathies (M46.-, M48.-)")

Diagnosis Index entries for M46.81

• Spondylopathy › inflammatory › specified type NEC › occipito-atlanto-axial region

Nearby codes

• M46.57 Other infective spondylopathies, lumbosacral region
• M46.58 Other infective spondylopathies, sacral and sacrococcygeal region
• M46.59 Other infective spondylopathies, multiple sites in spine
• M46.8 Other specified inflammatory spondylopathies
• M46.80 Other specified inflammatory spondylopathies, site unspecified
• M46.81 Other specified inflammatory spondylopathies, occipito-atlanto-axial region (this code)
• M46.82 Other specified inflammatory spondylopathies, cervical region
• M46.83 Other specified inflammatory spondylopathies, cervicothoracic region
• M46.84 Other specified inflammatory spondylopathies, thoracic region
• M46.85 Other specified inflammatory spondylopathies, thoracolumbar region
• M46.86 Other specified inflammatory spondylopathies, lumbar region