2026 ICD-10-CM Diagnosis Code M19.179Post-traumatic osteoarthritis, unspecified ankle and foot

ICD-10-CM Codes›M00–M99›M15-M19›M19

ICD-10-CM M19.179
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M19.179 is a billable ICD-10-CM diagnosis code for post-traumatic osteoarthritis, unspecified ankle and foot. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 553 through 554. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Osteoarthritis.

Code Identity

ICD-10-CM Code
M19.179
Billable Status
Yes — Valid for Submission
Code Describes
Post-traumatic osteoarthritis, unspecified ankle and foot
Short Description
Post-traumatic osteoarthritis, unspecified ankle and foot
Same as the full description in the CMS dataset.
Parent Code
M19.17
Post-traumatic osteoarthritis, ankle and foot

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM15-M19Osteoarthritis
CategoryM19Other and unspecified osteoarthritis
This CodeM19.179Post-traumatic osteoarthritis, unspecified ankle and foot

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Osteoarthritis of ankle secondary to trauma
  • Osteoarthritis of first metatarsophalangeal joint
  • Osteoarthritis of first metatarsophalangeal joint secondary to trauma
  • Osteoarthritis of midfoot
  • Osteoarthritis of midfoot secondary to trauma
  • Osteoarthritis of subtalar joint
  • Osteoarthritis of subtalar joint secondary to trauma
  • Osteoarthritis of talonavicular joint
  • Osteoarthritis of toe joint
  • Secondary osteoarthritis of ankle
  • Secondary osteoarthritis of first metatarsophalangeal joint
  • Secondary osteoarthritis of midfoot
  • Secondary osteoarthritis of subtalar joint
  • Secondary talonavicular osteoarthritis
  • Talonavicular osteoarthritis secondary to trauma
  • Traumatic arthropathy of 1st metatarsophalangeal joint
  • Traumatic arthropathy of talonavicular joint

Clinical ClassificationClinical

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

CCSR MUS006
Osteoarthritis
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Osteoarthritis

Osteoarthritis, sometimes called OA, is a type of arthritis that only affects the joints, usually in the hands, knees, hips, neck, and lower back. It's the most common type of arthritis.

The full article covers:

  • What is osteoarthritis?
  • What are the symptoms of osteoarthritis?
  • What causes osteoarthritis?
  • Who is more likely to develop osteoarthritis?
  • How is osteoarthritis diagnosed?
  • What are the treatments for osteoarthritis?

Read the full article at MedlinePlus

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

Convert M19.179 to ICD-9-CMHistory

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

ICD-9-CM
715.27 Loc 2nd osteoarthr-ankle
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 M19.179Overview

Is M19.179 (Post-traumatic osteoarthritis, ankle and foot) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report post-traumatic osteoarthritis, unspecified ankle and foot on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M19.179 group to?

When post-traumatic osteoarthritis, unspecified ankle and foot is the principal diagnosis on an inpatient stay, it groups to MS-DRG 553, 554, with relative weights from 0.8301 to 1.2963 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M19.179?

Under the General Equivalence Mappings, post-traumatic osteoarthritis, unspecified ankle and foot converts to ICD-9-CM 715.27 (loc 2nd osteoarthr-ankle). 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.