2026 ICD-10-CM Diagnosis Code M43.8X1Other specified deforming dorsopathies, occipito-atlanto-axial region

ICD-10-CM Codes›M00–M99›M40-M43›M43

ICD-10-CM M43.8X1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M43.8X1 is a billable ICD-10-CM diagnosis code for other specified deforming dorsopathies, 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
M43.8X1
Billable Status
Yes — Valid for Submission
Code Describes
Other specified deforming dorsopathies, occipito-atlanto-axial region
Short Description
Oth deforming dorsopathies, occipito-atlanto-axial region
Parent Code
M43.8X
Other specified deforming dorsopathies

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM43Other deforming dorsopathies
This CodeM43.8X1Other specified deforming dorsopathies, 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

Patient EducationClinical

Spine Injuries and Disorders

Your backbone, or spine, is made up of 26 bone discs called vertebrae. The vertebrae protect your spinal cord and allow you to stand and bend. A number of problems can change the structure of the spine or damage the vertebrae and surrounding tissue. They include:

Read the full article at MedlinePlus

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

Convert M43.8X1 to ICD-9-CMHistory

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

ICD-9-CM
737.8 Curvature of spine NEC
Approximate The match is approximate rather than exact.
ICD-9-CM
737.9 Curvature of spine NOS
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 M43.8X1Overview

What is the ICD-10 code for other specified deforming dorsopathies, occipito-atlanto-axial region?

The ICD-10-CM code for other specified deforming dorsopathies, occipito-atlanto-axial region is M43.8X1 (sometimes written as M438X1). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Is M43.8X1 (Other specified deforming dorsopathies) a billable code?

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

What MS-DRG does M43.8X1 group to?

When other specified deforming dorsopathies, 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 M43.8X1?

Under the General Equivalence Mappings, other specified deforming dorsopathies, occipito-atlanto-axial region converts to ICD-9-CM 737.8 (curvature of spine NEC) and 737.9 (curvature of spine NOS). The mapping is approximate, so confirm the match fits the documentation.