2026 ICD-10-CM Diagnosis Code M46.41Discitis, unspecified, occipito-atlanto-axial region

ICD-10-CM Codes›M00–M99›M45-M49›M46

ICD-10-CM M46.41
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M46.41 is a billable ICD-10-CM diagnosis code for discitis, unspecified, 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. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M46.41
Billable Status
Yes — Valid for Submission
Code Describes
Discitis, unspecified, occipito-atlanto-axial region
Short Description
Discitis, unspecified, occipito-atlanto-axial region
Same as the full description in the CMS dataset.
Parent Code
M46.4
Discitis, unspecified

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM45-M49Spondylopathies
CategoryM46Other inflammatory spondylopathies
This CodeM46.41Discitis, unspecified, occipito-atlanto-axial region

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Discitis, diskitis
      • occipito-atlanto-axial region

Clinical ClassificationClinical

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

CCSR MUS011
Spondylopathies/spondyloarthropathy (including infective)
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Discitis

    inflammation of an intervertebral disc or disk space which may lead to disk erosion. until recently, discitis has been defined as a nonbacterial inflammation and has been attributed to aseptic processes (e.g., chemical reaction to an injected substance). however, recent studies provide evidence that infection may be the initial cause, but perhaps not the promoter, of most cases of discitis. discitis has been diagnosed in patients following discography, myelography, lumbar puncture, paravertebral injection, and obstetrical epidural anesthesia. discitis following chemonucleolysis (especially with chymopapain) is attributed to chemical reaction by some and to introduction of microorganisms by others.

  • Intervertebral Disc

    any of the 23 plates of fibrocartilage found between the bodies of adjacent vertebrae.

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 M46.41 to ICD-9-CMHistory

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

ICD-9-CM
722.91 Disc dis NEC/NOS-cerv
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 M46.41Overview

Is M46.41 (Discitis, unspecified) a billable code?

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

What MS-DRG does M46.41 group to?

When discitis, unspecified, occipito-atlanto-axial region is the principal diagnosis on an inpatient stay, it groups to MS-DRG 551, 552, with relative weights from 0.9613 to 1.6761 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M46.41?

Under the General Equivalence Mappings, discitis, unspecified, occipito-atlanto-axial region converts to ICD-9-CM 722.91 (disc dis NEC/NOS-cerv). 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.