2026 ICD-10-CM Diagnosis Code M05.871Other rheumatoid arthritis with rheumatoid factor of right ankle and foot

ICD-10-CM Codes›M00–M99›M05-M14›M05

ICD-10-CM M05.871
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M05.871 is a billable ICD-10-CM diagnosis code for other rheumatoid arthritis with rheumatoid factor of right ankle and foot. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 545 through 547. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Rheumatoid arthritis and related disease.

This medical diagnosis code is frequently used in Orthopedics medical specialties to designate conditions such rheumatoid arthritis.

Code Identity

ICD-10-CM Code
M05.871
Billable Status
Yes — Valid for Submission
Code Describes
Other rheumatoid arthritis with rheumatoid factor of right ankle and foot
Short Description
Oth rheumatoid arthritis w rheumatoid factor of right ank/ft
Parent Code
M05.87
Other rheumatoid arthritis with rheumatoid factor of ankle and foot

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM05Rheumatoid arthritis with rheumatoid factor
This CodeM05.871Other rheumatoid arthritis with rheumatoid factor of right ankle and foot

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Bilateral rheumatoid arthritis of feet
  • Bilateral seropositive rheumatoid arthritis of ankle joints
  • Bilateral seropositive rheumatoid arthritis of feet
  • Left ankle seropositive rheumatoid arthritis
  • Left foot seropositive rheumatoid arthritis
  • Rheumatoid arthritis of ankle
  • Rheumatoid arthritis of bilateral ankles
  • Rheumatoid arthritis of left ankle
  • Rheumatoid arthritis of left foot
  • Rheumatoid arthritis of right ankle
  • Rheumatoid arthritis of right foot
  • Right ankle seropositive rheumatoid arthritis
  • Right foot seropositive rheumatoid arthritis

Clinical ClassificationClinical

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

CCSR MUS003
Rheumatoid arthritis and related disease
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a form of arthritis that causes pain, swelling, and stiffness in your joints. RA is an autoimmune disease. Although it is most common in the wrist and fingers, this disease can cause your immune system to attack any joint tissue. The inflammation (swelling) that comes with RA can also affect other body parts.

The full article covers:

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

Read the full article at MedlinePlus

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

Convert M05.871 to ICD-9-CMHistory

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

ICD-9-CM
714.0 Rheumatoid arthritis
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 M05.871Overview

Is M05.871 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report other rheumatoid arthritis with rheumatoid factor of right ankle and foot on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does M05.871 group to?

When other rheumatoid arthritis with rheumatoid factor of right ankle and foot is the principal diagnosis on an inpatient stay, it groups to MS-DRG 545, 546, 547, with relative weights from 0.8362 to 2.4817 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of M05.871?

Under the General Equivalence Mappings, other rheumatoid arthritis with rheumatoid factor of right ankle and foot converts to ICD-9-CM 714.0 (rheumatoid arthritis). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.