2027 ICD-10-CM Diagnosis Code M24.273Disorder of ligament, unspecified ankle

ICD-10-CM Codes›M00–M99›M20-M25›M24

ICD-10-CM M24.273
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

M24.273 is a billable ICD-10-CM diagnosis code for disorder of ligament, unspecified ankle. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 557 through 558. Coders also document this condition as disorder of ligament of ankle joint. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M24.273
Billable Status
Yes — Valid for Submission
Code Describes
Disorder of ligament, unspecified ankle
Short Description
Disorder of ligament, unspecified ankle
Same as the full description in the CMS dataset.
Parent Code
M24.27
Disorder of ligament, ankle and foot

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM20-M25Other joint disorders
CategoryM24Other specific joint derangements
This CodeM24.273Disorder of ligament, unspecified ankle

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Disorder of ligament of ankle joint
  • Lesion of ligaments of the ankle region
  • Ligamentous laxity of ankle region

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to M24.273: its own notes plus those printed at M24.2, M24, block M00-M25, block M20-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

Excludes1

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

From M24.2 Disorder of ligament applies to 24 codes
  • familial ligamentous laxity (M35.7)
From M24 Other specific joint derangements applies to 205 codes
  • current injury - see injury of joint by body region

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 M24.2 Disorder of ligament applies to 24 codes
From M24 Other specific joint derangements applies to 205 codes
From Block M20-M25 Other joint disorders applies to 719 codes
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 M24.273, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming M24.273: they are not reported together with it, unless the two conditions are unrelated.

  • M25.3 Other instability of joint
    instability of joint secondary to old ligament injury (M24.2-) names M24.2-, which includes this code
  • M35.7 Hypermobility syndrome
    ligamentous laxity, NOS (M24.2-) names M24.2-, which includes this code

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

Ankle Injuries and Disorders

Your ankle bone and the ends of your two lower leg bones make up the ankle joint. Your ligaments, which connect bones to one another, stabilize and support it. Your muscles and tendons move it.

Read the full article at MedlinePlus

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

Convert M24.273 to ICD-9-CMHistory

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

ICD-9-CM
728.4 Laxity of ligament
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 M24.273Overview

What is the ICD-10 code for disorder of ligament, unspecified ankle?

The ICD-10-CM code for disorder of ligament, unspecified ankle is M24.273 (sometimes written as M24273). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is M24.273 (Disorder of ligament, ankle and foot) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report disorder of ligament, unspecified ankle on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does M24.273 group to?

When disorder of ligament, unspecified ankle is the principal diagnosis on an inpatient stay, it groups to MS-DRG 557, 558, with relative weights from 0.8873 to 1.4883 depending on complications. Higher weights mean higher Medicare reimbursement.

Can M24.273 be reported with M35.7?

Not as a rule. The Excludes1 note at M24.2, which applies to M24.273, lists "familial ligamentous laxity (M35.7)". 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).

What is the ICD-9 equivalent of M24.273?

Under the General Equivalence Mappings, disorder of ligament, unspecified ankle converts to ICD-9-CM 728.4 (laxity of ligament). The mapping is approximate, so confirm the match fits the documentation.