2027 ICD-10-CM Diagnosis Code M42.9Spinal osteochondrosis, unspecified

ICD-10-CM Codes›M00–M99›M40-M43›M42

ICD-10-CM M42.9
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M42.9 is a billable ICD-10-CM diagnosis code for spinal osteochondrosis, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 553 through 554. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Scoliosis and other postural dorsopathic deformities.

Code Identity

ICD-10-CM Code
M42.9
Billable Status
Yes — Valid for Submission
Code Describes
Spinal osteochondrosis, unspecified
Short Description
Spinal osteochondrosis, unspecified
Same as the full description in the CMS dataset.
Parent Code
M42
Spinal osteochondrosis

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM40-M43Deforming dorsopathies
CategoryM42Spinal osteochondrosis
This CodeM42.9Spinal osteochondrosis, unspecified

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M42.9: its own notes plus those printed at Chapter 13. A note printed at a category, block or chapter applies to every code under it.

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 M42.9, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming M42.9: they are not reported together with it, unless the two conditions are unrelated.

  • M40.0 Postural kyphosis
    osteochondrosis of spine (M42.-) names M42.-, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming M42.9: its condition is not part of those codes, and both may be reported when the patient has both.

  • M93 Other osteochondropathies
    osteochondrosis of spine (M42.-) names M42.-, which includes this code

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 MUS022
Scoliosis and other postural dorsopathic deformities
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Spinal Osteochondrosis

    a bone disorder involving ossification centers (epiphyses) of the vertebral column.

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 M42.9 to ICD-9-CMHistory

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

ICD-9-CM
732.9 Osteochondropathy 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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M42.9Overview

What is the ICD-10 code for spinal osteochondrosis, unspecified?

The ICD-10-CM code for spinal osteochondrosis, unspecified is M42.9 (sometimes written as M429). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M42.9 (Spinal osteochondrosis) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report spinal osteochondrosis, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M42.9 group to?

When spinal osteochondrosis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 554, 553, with relative weights from 0.8328 to 1.2492 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M42.9?

Under the General Equivalence Mappings, spinal osteochondrosis, unspecified converts to ICD-9-CM 732.9 (osteochondropathy NOS). The mapping is approximate, so confirm the match fits the documentation.