2026 ICD-10-CM Diagnosis Code M13.859Other specified arthritis, unspecified hip

ICD-10-CM Codes›M00–M99›M05-M14›M13

ICD-10-CM M13.859
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M13.859 is a billable ICD-10-CM diagnosis code for other specified arthritis, 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 allergic arthritis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified joint disorders.

Code Identity

ICD-10-CM Code
M13.859
Billable Status
Yes — Valid for Submission
Code Describes
Other specified arthritis, unspecified hip
Short Description
Other specified arthritis, unspecified hip
Same as the full description in the CMS dataset.
Parent Code
M13.85
Other specified arthritis, hip

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM13Other arthritis
This CodeM13.859Other specified arthritis, unspecified hip

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Allergic arthritis
  • Allergic arthritis of the pelvic region and thigh
  • Arthritis of hip
  • Arthropathy associated with a hypersensitivity reaction
  • Climacteric arthritis
  • Climacteric arthritis of the pelvic region and thigh
  • Inflammation of hip joint

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

Clinical InformationClinical

  • Allergic Arthritis

    arthritis occurring after the ingestion of allergenic substance(s).

  • Climacteric Arthritis

    arthritis that occurs during menopause.

Patient EducationClinical

Arthritis

If you feel pain and stiffness in your body or have trouble moving around, you might have arthritis. Any disorder that affects the joints is often called arthritis. Joints are places where two bones meet, such as your elbow or knee.

The full article covers:

  • What is arthritis?
  • What are the types of arthritis?
  • What are the symptoms of arthritis?
  • Who is more likely to get arthritis?
  • How is arthritis diagnosed?
  • What are the treatments for arthritis?

Read the full article at MedlinePlus

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

Convert M13.859 to ICD-9-CMHistory

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

ICD-9-CM
716.25 Allerg arthritis-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 M13.859Overview

Is M13.859 (Other specified arthritis, hip) a billable code?

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

What MS-DRG does M13.859 group to?

When other specified arthritis, 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 M13.859?

Under the General Equivalence Mappings, other specified arthritis, unspecified hip converts to ICD-9-CM 716.25 (allerg arthritis-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.