2026 ICD-10-CM Diagnosis Code M25.259Flail joint, unspecified hip

ICD-10-CM Codes›M00–M99›M20-M25›M25

ICD-10-CM M25.259
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M25.259 is a billable ICD-10-CM diagnosis code for flail joint, unspecified hip. 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. Coders also document this condition as flail joint of hip. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M25.259
Billable Status
Yes — Valid for Submission
Code Describes
Flail joint, unspecified hip
Short Description
Flail joint, unspecified hip
Same as the full description in the CMS dataset.
Parent Code
M25.25
Flail joint, hip

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM20-M25Other joint disorders
CategoryM25Other joint disorder, not elsewhere classified
This CodeM25.259Flail joint, unspecified hip

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Flail joint of hip

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

Hip Injuries and Disorders

Your hip is the joint where your femur (thigh bone) meets your pelvis (hip bone). There are two main parts: a ball at the end of the femur, which fits in a socket in the pelvis. Your hip is known as a ball-and-socket joint. This is because you have a ball at the end of your femur, and it fits into a socket in your pelvis.

Read the full article at MedlinePlus

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

Convert M25.259 to ICD-9-CMHistory

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

ICD-9-CM
718.85 Jt derangment NEC-pelvis
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 M25.259Overview

Is M25.259 (Flail joint, hip) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report flail joint, unspecified hip on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M25.259 group to?

When flail joint, unspecified hip 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 M25.259?

Under the General Equivalence Mappings, flail joint, unspecified hip converts to ICD-9-CM 718.85 (jt derangment NEC-pelvis). 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.