Primary osteoarthritis, other specified site

This code signifies the presence of primary osteoarthritis affecting a joint site not specifically categorized elsewhere in the M19.0 series. It indicates degenerative joint disease that is not secondary to another condition and impacts an anatomical location beyond common sites like the hip, knee, or hand.

Use this code when documentation clearly states primary osteoarthritis in a joint such as the ankle, shoulder, elbow, or wrist, and no more specific code (e.g., M16, M17, M18) is available. The medical record should explicitly identify the affected joint and confirm the primary nature of the osteoarthritis.

• Ensure the documentation specifies "primary" osteoarthritis; otherwise, consider codes for secondary osteoarthritis (M19.1-).
• Always attempt to find a more specific site code within the M19.0 series or other M-category codes (e.g., M16 for hip, M17 for knee, M18 for hand) before resorting to this "other specified site" code.
• If laterality is documented (e.g., right ankle), ensure the appropriate 7th character is appended if available for the specific site.