Other specified crystal arthropathies, right knee

This code signifies a diagnosis of an inflammatory joint condition affecting the right knee, caused by the deposition of crystals other than uric acid (gout) or calcium pyrophosphate dihydrate (CPPD). These crystal deposits lead to pain, swelling, and tenderness in the joint.

Use this code when documentation specifies a crystal arthropathy of the right knee that is not identified as gout or CPPD. This typically involves microscopic identification of non-gouty, non-CPPD crystals in synovial fluid or tissue biopsy from the right knee.

• Ensure the documentation explicitly states "right knee" and specifies a crystal arthropathy other than gout or CPPD.
• Do not use this code for unspecified crystal arthropathies; instead, refer to M11.9.
• Always review pathology reports for definitive crystal identification to support this diagnosis.