ICD10

ICD-10 Code M19.9: Osteoarthritis, unspecified site

M19.9 is an ICD-10 diagnosis entry used to group records related to Osteoarthritis, unspecified site. You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen. ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the musculoskeletal system and connective tissue (M00-M99).

Reviewed by HealthAssure Clinical TeamUpdated 21 May 2026

What is this code?

ICD-10 entries help standardize how diagnoses are organized for coding, reporting, analytics, and documentation. This code sits within the broader ICD-10 area for Diseases of the musculoskeletal system and connective tissue (M00-M99).

When is it used?

  • May be used when a clinician documents osteoarthritis, unspecified site in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code may act more like a grouping or parent code, so a more specific child code may be used in final documentation when available.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.
  • This entry may represent a broader category rather than the most specific billable code.

Code hierarchy

chapter
13Diseases of the musculoskeletal system and connective tissue (M00-M99)
block
M00-M25Arthropathies
block
M15-M19Osteoarthritis
category
M19Other and unspecified osteoarthritis
currentM19

Where you may see this code

You may see this entry in coding references, medical records, or claims workflows when a broader diagnosis category is being reviewed before a more specific code is chosen.

Related specialists

Orthopedic SpecialistRheumatologist

Coding guidelines

Compatibility

Legacy code aligns to an official FY 2026 category. Frontend should resolve to the official category page and surface the billable child codes.
Legacy codes
M19.9
Replacement codes
M19.90 — Unspecified osteoarthritis, unspecified siteM19.91 — Primary osteoarthritis, unspecified siteM19.92 — Post-traumatic osteoarthritis, unspecified siteM19.93 — Secondary osteoarthritis, unspecified site

Common synonyms

Osteoarthritis, unspecified siteOsteoarthritis

Frequently asked questions

Code details

CodeM19.9
SystemICD10
Display nameOsteoarthritis, unspecified site
ChapterDiseases of the musculoskeletal system and connective tissue (M00-M99)
BlockOsteoarthritis

Flags

BillableNo
Valid clinical useNo

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.