2027 ICD-10-CM Diagnosis Code M19.09Primary osteoarthritis, other specified site

ICD-10-CM Codes›M00–M99›M15-M19›M19

ICD-10-CM M19.09
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M19.09 is a billable ICD-10-CM diagnosis code for primary osteoarthritis, other specified site. 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 Osteoarthritis.

Code Identity

ICD-10-CM Code
M19.09
Billable Status
Yes — Valid for Submission
Code Describes
Primary osteoarthritis, other specified site
Short Description
Primary osteoarthritis, other specified site
Same as the full description in the CMS dataset.
Parent Code
M19.0
Primary osteoarthritis of other joints

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM15-M19Osteoarthritis
CategoryM19Other and unspecified osteoarthritis
This CodeM19.09Primary osteoarthritis, other specified site

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M19.09: its own notes plus those printed at M19, block M00-M25, block M15-M19, and Chapter 13. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Block M00-M25 applies to 2,249 codes
  • Disorders affecting predominantly peripheral (limb) joints

Excludes1

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

From M19 Other and unspecified osteoarthritis applies to 52 codes

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 M19 Other and unspecified osteoarthritis applies to 52 codes
  • arthrosis of spine (M47.-)
  • hallux rigidus (M20.2)
  • osteoarthritis of spine (M47.-)
From Block M15-M19 Osteoarthritis applies to 98 codes
  • osteoarthritis of spine (M47.-)
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 M19.09, its category, or a range that includes it.

Excludes1 5

These codes carry an Excludes1 note naming M19.09: they are not reported together with it, unless the two conditions are unrelated.

  • M12 Other and unspecified arthropathy
    arthrosis (M15-M19) names M15-M19, which includes this code
  • M13 Other arthritis
    arthrosis (M15-M19) names M15-M19, which includes this code
  • M13 Other arthritis
    osteoarthritis (M15-M19) names M15-M19, which includes this code
  • M13.8 Other specified arthritis
    osteoarthritis (M15-M19) names M15-M19, which includes this code
  • M15 Polyosteoarthritis
    bilateral involvement of single joint (M16-M19) names M16-M19, 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 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.

Code History & ChangesHistory

Replacement M19.09 replaces the following previously assigned code(s):

  • M19.91 - Primary osteoarthritis, unspecified site
FY 2021AddedAdded to the ICD-10-CM code setEffective October 1, 2020.
FY 2022–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M19.09Overview

What is the ICD-10 code for primary osteoarthritis, other specified site?

The ICD-10-CM code for primary osteoarthritis, other specified site is M19.09 (sometimes written as M1909). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M19.09 (Primary osteoarthritis of other joints) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report primary osteoarthritis, other specified site on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M19.09 group to?

When primary osteoarthritis, other specified site 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.

Can M19.09 be reported with a code from M15?

Not as a rule. The Excludes1 note at M19, which applies to M19.09, lists "polyarthritis (M15.-)". 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).