ICD-10 Code M02.86 – Other reactive arthropathies, knee (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M02.86 – Other reactive arthropathies, knee
What it is
M02.86 identifies a reactive arthropathy affecting the knee. Use it when the knee joint inflammation is linked to a reactive, postinfectious pattern and the record specifies the knee.
Clinical signs
Typical findings include knee pain, swelling, stiffness, and reduced range of motion. Clinical features vary; refer to documentation for the underlying trigger and whether the presentation is acute or persistent.
When to use this code
Use this code when the provider documents other reactive arthropathy involving the knee and does not assign a more specific reactive arthritis code. It is appropriate when the knee is the named joint in the diagnosis. Check documentation if the note only says arthritis, joint pain, or postinfectious arthritis without confirming the knee.
Do not use for
Do not use this code for osteoarthritis, rheumatoid arthritis, septic arthritis, or nonspecific knee pain. If the record does not clearly support a reactive arthropathy diagnosis, check documentation.
Coding tip
Verify that the knee is explicitly documented as the affected joint before assigning M02.86.