2026 ICD-10-CM Diagnosis Code M23.011Cystic meniscus, anterior horn of medial meniscus, right knee

ICD-10-CM Codes›M00–M99›M20-M25›M23

ICD-10-CM M23.011
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M23.011 is a billable ICD-10-CM diagnosis code for cystic meniscus, anterior horn of medial meniscus, right knee. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 562 through 563. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M23.011
Billable Status
Yes — Valid for Submission
Code Describes
Cystic meniscus, anterior horn of medial meniscus, right knee
Short Description
Cystic meniscus, anterior horn of medial meniscus, r knee
Parent Code
M23.01
Cystic meniscus, anterior horn of medial meniscus

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM20-M25Other joint disorders
CategoryM23Internal derangement of knee
This CodeM23.011Cystic meniscus, anterior horn of medial meniscus, right knee

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral cyst of meniscus of knees
  • Cyst of anterior horn of left medial meniscus
  • Cyst of anterior horn of medial meniscus of bilateral knees
  • Cyst of anterior horn of medial meniscus of knee
  • Cyst of anterior horn of right medial meniscus
  • Cyst of medial meniscus
  • Cyst of medial meniscus of left knee
  • Cyst of medial meniscus of right knee
  • Cyst of meniscus of left knee
  • Cyst of meniscus of right knee
  • Mass of bilateral knee joints

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 M23.011 to ICD-9-CMHistory

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

ICD-9-CM
717.1 Derang ant med meniscus
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 M23.011Overview

Is M23.011 (Cystic meniscus, anterior horn of medial meniscus) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report cystic meniscus, anterior horn of medial meniscus, right knee on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M23.011 group to?

When cystic meniscus, anterior horn of medial meniscus, right knee is the principal diagnosis on an inpatient stay, it groups to MS-DRG 562, 563, with relative weights from 0.8955 to 1.4248 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M23.011?

Under the General Equivalence Mappings, cystic meniscus, anterior horn of medial meniscus, right knee converts to ICD-9-CM 717.1 (derang ant med meniscus). 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.