2026 ICD-10-CM Diagnosis Code M12.859Other specific arthropathies, not elsewhere classified, unspecified hip

ICD-10-CM Codes›M00–M99›M05-M14›M12

ICD-10-CM M12.859
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M12.859 is a billable ICD-10-CM diagnosis code for other specific arthropathies, not elsewhere classified, unspecified hip. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 553 through 554. Coders also document this condition as transient arthropathy of the pelvic region and thigh. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M12.859
Billable Status
Yes — Valid for Submission
Code Describes
Other specific arthropathies, not elsewhere classified, unspecified hip
Short Description
Oth specific arthropathies, NEC, unsp hip
Parent Code
M12.85
Other specific arthropathies, not elsewhere classified, hip

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM12Other and unspecified arthropathy
This CodeM12.859Other specific arthropathies, not elsewhere classified, unspecified hip

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Transient arthropathy of the pelvic region and thigh

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 M12.859 to ICD-9-CMHistory

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

ICD-9-CM
716.45 Trans arthropathy-pelvis
Approximate The match is approximate rather than exact.
ICD-9-CM
716.85 Arthropathy 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 M12.859Overview

Is M12.859 (Other specific arthropathies, not elsewhere classified, hip) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other specific arthropathies, not elsewhere classified, unspecified hip on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M12.859 group to?

When other specific arthropathies, not elsewhere classified, unspecified hip is the principal diagnosis on an inpatient stay, it groups to MS-DRG 553, 554, with relative weights from 0.8301 to 1.2963 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M12.859?

Under the General Equivalence Mappings, other specific arthropathies, not elsewhere classified, unspecified hip converts to ICD-9-CM 716.45 (trans arthropathy-pelvis) and 716.85 (arthropathy 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.