2026 ICD-10-CM Diagnosis Code M08.90Juvenile arthritis, unspecified, unspecified site

ICD-10-CM CodesM00–M99M05-M14M08

ICD-10-CM M08.90
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

M08.90 is a billable ICD-10-CM diagnosis code for juvenile arthritis, unspecified, unspecified site. 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 Juvenile arthritis.

Code Identity

ICD-10-CM Code
M08.90
Billable Status
Yes — Valid for Submission
Code Describes
Juvenile arthritis, unspecified, unspecified site
Short Description
Juvenile arthritis, unspecified, unspecified site
Same as the full description in the CMS dataset.
Parent Code
Juvenile arthritis, unspecified

Code Classification

ChapterM00–M99Diseases of the musculoskeletal system and connective tissue
SectionM05-M14Inflammatory polyarthropathies
CategoryM08Juvenile arthritis
This CodeM08.90Juvenile arthritis, unspecified, unspecified site

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Acute arthritis
  • Acute arthropathy
  • Arthritis
  • Arthritis co-occurrent and due to Crohn's disease
  • Arthritis of finger of right hand
  • Arthritis of left sacroiliac joint
  • Arthritis of right sacroiliac joint
  • Arthritis of right sternoclavicular joint
  • Arthritis of temporomandibular joint as part of polyarthritis
  • Arthropathy
  • Asymmetrical arthritis
  • Bilateral arthritis of sacroiliac joint
  • Bilateral arthropathy of sacroiliac joints
  • Bilateral sacroiliitis
  • Chronic arthritis
  • Cricoarytenoid joint arthritis
  • Disorder of left sacroiliac joint
  • Disorder of right sacroiliac joint
  • Exacerbation of osteoarthritis
  • Extraintestinal Crohn's
  • Generalized arthritis
  • Human leukocyte antigen B27 negative arthropathy
  • Immune dysregulation, inflammatory bowel disease, arthritis, recurrent infection syndrome
  • Inflammation of joint
  • Juvenile arthritis in Crohn disease
  • Juvenile arthritis in ulcerative colitis
  • Juvenile arthritis of inflammatory bowel disease
  • Large joint arthritis
  • Lower limb joint arthritis
  • Pain due to arthritis
  • Sacroiliitis of left sacroiliac joint
  • Sacroiliitis of right sacroiliac joint
  • Small joint arthritis
  • Subacute arthritis
  • Subacute arthropathy
  • Symmetrical arthritis
  • Thoracic arthritis

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Arthritis, arthritic(acute) (chronic) (nonpyogenic) (subacute)
      • juvenile

Clinical ClassificationClinical

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

CCSR MUS004
Juvenile arthritis
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Arthritis

    acute or chronic inflammation of joints.
  • Arthritis, Experimental

    arthritis that is induced in experimental animals. immunological methods and infectious agents can be used to develop experimental arthritis models. these methods include injections of stimulators of the immune response, such as an adjuvant (adjuvants, immunologic) or collagen.
  • Arthritis, Gouty

    arthritis, especially of the great toe, as a result of gout. acute gouty arthritis often is precipitated by trauma, infection, surgery, etc. the initial attacks are usually monoarticular but later attacks are often polyarticular. acute and chronic gouty arthritis are associated with accumulation of monosodium urate in and around affected joints.
  • Arthritis, Infectious

    arthritis caused by bacteria; rickettsia; mycoplasma; viruses; fungi; or parasites.
  • Arthritis, Juvenile

    arthritis in children, with onset before 16 years of age. the terms juvenile rheumatoid arthritis (jra) and juvenile idiopathic arthritis (jia) refer to classification systems for chronic arthritis in children. only one subtype of juvenile arthritis (polyarticular-onset, rheumatoid factor-positive) clinically resembles adult rheumatoid arthritis and is considered its childhood equivalent.
  • Arthritis, Psoriatic

    a type of inflammatory arthritis associated with psoriasis, often involving the axial joints and the peripheral terminal interphalangeal joints. it is characterized by the presence of hla-b27-associated spondylarthropathy, and the absence of rheumatoid factor.
  • Arthritis, Reactive

    an aseptic, inflammatory arthritis developing secondary to a primary extra-articular infection, most typically of the gastrointestinal tract or urogenital system. the initiating trigger pathogens are usually shigella; salmonella; yersinia; campylobacter; or chlamydia trachomatis. reactive arthritis is strongly associated with hla-b27 antigen.
  • Arthritis, Rheumatoid

    a chronic systemic disease, primarily of the joints, marked by inflammatory changes in the synovial membranes and articular structures, widespread fibrinoid degeneration of the collagen fibers in mesenchymal tissues, and by atrophy and rarefaction of bony structures. etiology is unknown, but autoimmune mechanisms have been implicated.
  • Arthritis-Encephalitis Virus, Caprine

    a species of lentivirus, subgenus ovine-caprine lentiviruses (lentiviruses, ovine-caprine), closely related to visna-maedi virus and causing acute encephalomyelitis; chronic arthritis; pneumonia; mastitis; and glomerulonephritis in goats. it is transmitted mainly in the colostrum and milk.
  • Crystal Arthropathies

    joint disorders that are characterized by accumulation of microcrystals in and around the joint including in the synovial fluid. they are classified according to the chemical nature of the crystals such as calcium pyrophosphate; basic calcium phosphates; and monosodium urate (see uric acid).
  • Lyme Disease

    an infectious disease caused by a spirochete, borrelia burgdorferi, which is transmitted chiefly by ixodes dammini (see ixodes) and pacificus ticks in the united states and ixodes ricinis (see ixodes) in europe. it is a disease with early and late cutaneous manifestations plus involvement of the nervous system, heart, eye, and joints in variable combinations. the disease was formerly known as lyme arthritis and first discovered at old lyme, connecticut.
  • Osteoarthritis

    a progressive, degenerative joint disease, the most common form of arthritis, especially in older persons. the disease is thought to result not from the aging process but from biochemical changes and biomechanical stresses affecting articular cartilage. in the foreign literature it is often called osteoarthrosis deformans.
  • Rheumatic Fever

    a febrile disease occurring as a delayed sequela of infections with streptococcus pyogenes. it is characterized by multiple focal inflammatory lesions of the connective tissue structures, such as the heart, blood vessels, and joints (polyarthritis) and brain, and by the presence of aschoff bodies in the myocardium and skin.
  • Spondylarthritis

    inflammation of the joints of the spine, the intervertebral articulations.
  • Joints

    also known as articulations, these are points of connection between the ends of certain separate bones, or where the borders of other bones are juxtaposed.
  • Spine

    the spinal or vertebral column.

Patient EducationClinical

Juvenile Arthritis

Juvenile arthritis (JA) is arthritis that happens in children. It causes joint inflammation (swelling), pain, stiffness, and loss of motion. Joints are places where two bones meet, such as your elbow or knee. It can affect any joint, but it is more common in the knees, hands, and feet.

The full article covers:

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

Read the full article at MedlinePlus

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

Convert M08.90 to ICD-9-CMHistory

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

ICD-9-CM
714.30 Juv rheum arthritis NOS
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 M08.90Overview

Is M08.90 (Juvenile arthritis, unspecified) a billable code?

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

What MS-DRG does M08.90 group to?

When juvenile arthritis, unspecified, unspecified site 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 M08.90?

Under the General Equivalence Mappings, juvenile arthritis, unspecified, unspecified site converts to ICD-9-CM 714.30 (juv rheum arthritis NOS). 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.