2026 ICD-10-CM Diagnosis Code M49.81Spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region

ICD-10-CM Codes›M00–M99›M45-M49›M49

ICD-10-CM M49.81
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M49.81 is a billable ICD-10-CM diagnosis code for spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 551 through 552. The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M49.81
Billable Status
Yes — Valid for Submission
Code Describes
Spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region
Short Description
Spond in diseases classd elswhr, occipt-atlan-ax region
Parent Code
M49.8
Spondylopathy in diseases classified elsewhere

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM45-M49Spondylopathies
CategoryM49Spondylopathies in diseases classified elsewhere
This CodeM49.81Spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region

Code EditsBilling

Medicare Code Editor checks that affect claim validity for M49.81.

Manifestation diagnoses
Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and therefore should not be used as a principal diagnosis.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR MUS011
Spondylopathies/spondyloarthropathy (including infective)
Default principal diagnosis: inpatient No · outpatient No

Patient EducationClinical

Neck Injuries and Disorders

Any part of your neck - muscles, bones, joints, tendons, ligaments, or nerves - can cause neck problems. Neck pain is very common. Pain may also come from your shoulder, jaw, head, or upper arms.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert M49.81 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
720.81 Spondylopathy in oth dis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About M49.81Overview

Is M49.81 (Spondylopathy in diseases classified elsewhere) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M49.81 group to?

On inpatient claims, spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region maps to MS-DRG 551, 552, with relative weights from 0.9613 to 1.6761 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M49.81 be a principal diagnosis?

No. This is a manifestation code: spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.

What is the ICD-9 equivalent of M49.81?

Under the General Equivalence Mappings, spondylopathy in diseases classified elsewhere, occipito-atlanto-axial region converts to ICD-9-CM 720.81 (spondylopathy in oth dis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.