2027 ICD-10-CM Diagnosis Code M43.3Recurrent atlantoaxial dislocation with myelopathy

ICD-10-CM Codes›M00–M99›M40-M43›M43

ICD-10-CM M43.3
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M43.3 is a billable ICD-10-CM diagnosis code for recurrent atlantoaxial dislocation with myelopathy. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 564 through 566. Coders also document this condition as recurrent atlantoaxial subluxation with myelopathy. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Spondylopathies/spondyloarthropathy (including infective).

Code Identity

ICD-10-CM Code
M43.3
Billable Status
Yes — Valid for Submission
Code Describes
Recurrent atlantoaxial dislocation with myelopathy
Short Description
Recurrent atlantoaxial dislocation with myelopathy
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 CodeM43.3Recurrent atlantoaxial dislocation with myelopathy

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Recurrent atlantoaxial subluxation with myelopathy
  • Subluxation of atlantoaxial joint

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M43.3: its own notes plus those printed at M43 and Chapter 13. A note printed at a category, block or chapter applies to every code under it.

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From M43 Other deforming dorsopathies applies to 50 codes
  • congenital spondylolysis and spondylolisthesis (Q76.2)
  • hemivertebra (Q76.3-Q76.4)
  • Klippel-Feil syndrome (Q76.1)
  • lumbarization and sacralization (Q76.4)
  • platyspondylisis (Q76.4)
  • spina bifida occulta (Q76.0)
  • spinal curvature in osteoporosis (M80.-)
  • spinal curvature in Paget's disease of bone [osteitis deformans] (M88.-)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Notes

General instructions on how these codes are used.

From Chapter 13 (M00-M99) Diseases of the musculoskeletal system and connective tissue applies to 6,687 codes
  • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name M43.3, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming M43.3: they are not reported together with it, unless the two conditions are unrelated.

Excludes2 1

These codes carry an Excludes2 note naming M43.3: its condition is not part of those codes, and both may be reported when the patient has both.

  • M24.4 Recurrent dislocation of joint
    recurrent vertebral dislocation (M43.3-, M43.4, M43.5-)

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

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 M43.3 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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M43.3Overview

What is the ICD-10 code for recurrent atlantoaxial dislocation with myelopathy?

The ICD-10-CM code for recurrent atlantoaxial dislocation with myelopathy is M43.3 (sometimes written as M433). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M43.3 (Other deforming dorsopathies) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report recurrent atlantoaxial dislocation with myelopathy on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M43.3 group to?

When recurrent atlantoaxial dislocation with myelopathy is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 566, 565, with relative weights from 0.7374 to 1.4909 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M43.3 be reported with Q76.2?

Not as a rule. The Excludes1 note at M43, which applies to M43.3, lists "congenital spondylolysis and spondylolisthesis (Q76.2)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

What is the ICD-9 equivalent of M43.3?

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