2026 ICD-10-CM Diagnosis Code M19.90Unspecified osteoarthritis, unspecified site

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

• 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.

• Osteoarthritis, Hip

  noninflammatory degenerative disease of the hip joint which usually appears in late middle or old age. it is characterized by growth or maturational disturbances in the femoral neck and head, as well as acetabular dysplasia. a dominant symptom is pain on weight-bearing or motion.

• Osteoarthritis, Knee

  noninflammatory degenerative disease of the knee joint consisting of three large categories: conditions that block normal synchronous movement, conditions that produce abnormal pathways of motion, and conditions that cause stress concentration resulting in changes to articular cartilage. (crenshaw, campbell's operative orthopaedics, 8th ed, p2019)

• Osteoarthritis, Spine

  a degenerative joint disease involving the spine. it is characterized by progressive deterioration of the spinal articular cartilage (cartilage, articular), usually with hardening of the subchondral bone and outgrowth of bone spurs (osteophyte).

• 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.

Osteoarthritis

Osteoarthritis, sometimes called OA, is a type of arthritis that only affects the joints, usually in the hands, knees, hips, neck, and lower back. It's the most common type of arthritis.

The full article covers:

• What is osteoarthritis?
• What are the symptoms of osteoarthritis?
• What causes osteoarthritis?
• Who is more likely to develop osteoarthritis?
• How is osteoarthritis diagnosed?
• What are the treatments for osteoarthritis?

Read the full article at MedlinePlus

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