2026 ICD-10-CM Diagnosis Code M43.4Other recurrent atlantoaxial dislocation

ICD-10-CM Codes›M00–M99›M40-M43›M43

ICD-10-CM M43.4
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M43.4 is a billable ICD-10-CM diagnosis code for other recurrent atlantoaxial dislocation. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 564 through 566. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M43.4
Billable Status
Yes — Valid for Submission
Code Describes
Other recurrent atlantoaxial dislocation
Short Description
Other recurrent atlantoaxial dislocation
Same as the full description in the CMS dataset.
Parent Code
M43
Other deforming dorsopathies

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM43Other deforming dorsopathies
This CodeM43.4Other recurrent atlantoaxial dislocation

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.

    • Dislocation(articular)
      • recurrent
        • vertebra
          • atlantoaxial
    • Subluxation
      • atlantoaxial, recurrent

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

Patient EducationClinical

Dislocations

Dislocations are joint injuries that force the ends of your bones out of position. The cause is often a fall or a blow, sometimes from playing a contact sport. You can dislocate your ankles, knees, shoulders, hips, elbows and jaw. You can also dislocate your finger and toe joints.

Read the full article at MedlinePlus

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

Convert M43.4 to ICD-9-CMHistory

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

ICD-9-CM
718.38 Recur dislocat-jt NEC
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 M43.4Overview

Is M43.4 (Other deforming dorsopathies) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other recurrent atlantoaxial dislocation on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M43.4 group to?

When other recurrent atlantoaxial dislocation is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 565, 566, with relative weights from 0.7493 to 1.5436 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M43.4?

Under the General Equivalence Mappings, other recurrent atlantoaxial dislocation converts to ICD-9-CM 718.38 (recur dislocat-jt NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.