ICD-10 Code M02.359 – Reiter’s disease, unspecified hip (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code M02.359 – Reiter’s disease, unspecified hip
What it is
This code identifies Reiter’s disease, also called reactive arthritis, affecting the hip without a more specific side or detail documented. Use it when the hip joint is involved and the record does not specify laterality or another qualifier.
Clinical signs
Clinical features vary; refer to documentation. Typical findings may include inflammatory joint pain, swelling, stiffness, and reduced hip range of motion, usually in a reactive arthritis pattern after an infection.
When to use this code
Use M02.359 when the provider documents Reiter’s disease or reactive arthritis in the hip and does not identify the right or left hip. It may also fit when the chart confirms hip involvement but remains nonspecific. Check documentation if another joint or a different cause is recorded.
Do not use for
Do not use this code for hip pain without a documented diagnosis of Reiter’s disease. Do not use it when the record specifies a different joint, a different laterality, or another inflammatory arthropathy.
Coding tip
If the note does not clearly state the hip side, unspecified hip is appropriate; otherwise, code the documented laterality.