2027 ICD-10-CM Diagnosis Code M11.161Familial chondrocalcinosis, right knee

ICD-10-CM Codes›M00–M99›M05-M14›M11

ICD-10-CM M11.161
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M11.161 is a billable ICD-10-CM diagnosis code for familial chondrocalcinosis, right knee. 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. Coders also document this condition as chondrocalcinosis of joint of right knee. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Crystal arthropathies (excluding gout).

Code Identity

ICD-10-CM Code
M11.161
Billable Status
Yes — Valid for Submission
Code Describes
Familial chondrocalcinosis, right knee
Short Description
Familial chondrocalcinosis, right knee
Same as the full description in the CMS dataset.
Parent Code
M11.16
Familial chondrocalcinosis, knee

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM11Other crystal arthropathies
This CodeM11.161Familial chondrocalcinosis, right knee

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Chondrocalcinosis of joint of right knee
  • Chondrocalcinosis of knee joint
  • Degenerative disorder of articular cartilage of right knee
  • Familial calcium pyrophosphate deposition of right knee
  • Familial chondrocalcinosis

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M11.161: its own notes plus those printed at block M00-M25 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

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 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 M11.161, its category, or a range that includes it.

Excludes1 1

These codes carry an Excludes1 note naming M11.161: they are not reported together with it, unless the two conditions are unrelated.

  • E83.5 Disorders of calcium metabolism
    chondrocalcinosis (M11.1-M11.2) names M11.1-M11.2, which includes this code

Excludes2 1

These codes carry an Excludes2 note naming M11.161: its condition is not part of those codes, and both may be reported when the patient has both.

  • M24.1 Other articular cartilage disorders
    chondrocalcinosis (M11.1-, M11.2-) names M11.1-, which includes this code

Clinical ClassificationClinical

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

CCSR MUS034
Crystal arthropathies (excluding gout)
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Gout

Gout is a common type of inflammatory arthritis. It causes pain, swelling, and redness in one or more joints. It usually happens as a flare, which can last for a week or two and then gets better. The flares often begin in your big toe or a lower limb.

The full article covers:

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

Read the full article at MedlinePlus

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

Convert M11.161 to ICD-9-CMHistory

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

ICD-9-CM
712.36 Chondrocalcin NOS-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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About M11.161Overview

What is the ICD-10 code for familial chondrocalcinosis, right knee?

The ICD-10-CM code for familial chondrocalcinosis, right knee is M11.161 (sometimes written as M11161). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M11.161 (Familial chondrocalcinosis, knee) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report familial chondrocalcinosis, right knee on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M11.161 group to?

When familial chondrocalcinosis, right knee 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.

What is the ICD-9 equivalent of M11.161?

Under the General Equivalence Mappings, familial chondrocalcinosis, right knee converts to ICD-9-CM 712.36 (chondrocalcin NOS-l/leg). The mapping is approximate, so confirm the match fits the documentation.