2026 ICD-10-CM Diagnosis Code M25.361Other instability, right knee

ICD-10-CM Codes›M00–M99›M20-M25›M25

ICD-10-CM M25.361
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M25.361 is a billable ICD-10-CM diagnosis code for other instability, right knee. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 564 through 566. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M25.361
Billable Status
Yes — Valid for Submission
Code Describes
Other instability, right knee
Short Description
Other instability, right knee
Same as the full description in the CMS dataset.
Parent Code
M25.36
Other instability, knee

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM20-M25Other joint disorders
CategoryM25Other joint disorder, not elsewhere classified
This CodeM25.361Other instability, right knee

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral instability of joints of knees
  • Bilateral instability of patellofemoral joints
  • Instability of joint of left knee
  • Instability of joint of right knee
  • Instability of left patellofemoral joint
  • Instability of right patellofemoral joint
  • Patellar instability

Clinical ClassificationClinical

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

CCSR MUS007
Other specified joint disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Knee Injuries and Disorders

Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt or diseased, you have knee problems. Knee problems can cause pain and difficulty walking.

Read the full article at MedlinePlus

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

Convert M25.361 to ICD-9-CMHistory

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

ICD-9-CM
718.86 Jt derangement NEC-l/leg
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 M25.361Overview

Is M25.361 (Other instability, knee) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other instability, right knee on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M25.361 group to?

When other instability, right knee is the principal diagnosis on an inpatient stay, it groups to MS-DRG 564, 565, 566, with relative weights from 0.7493 to 1.5436 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M25.361?

Under the General Equivalence Mappings, other instability, right knee converts to ICD-9-CM 718.86 (jt derangement NEC-l/leg). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.