Villonodular synovitis (pigmented), multiple sites

This code represents pigmented villonodular synovitis (PVNS) affecting multiple joints or sites throughout the body. PVNS is a rare, benign proliferative disorder of the synovial membrane, characterized by villous and nodular growths that contain hemosiderin deposits, giving them a brownish color. It can lead to joint pain, swelling, and destructive changes if left untreated.

Use this code when documentation explicitly states pigmented villonodular synovitis is present in more than one anatomical location. This diagnosis is typically confirmed through imaging (MRI) and often biopsy. The physician's notes should clearly indicate the multi-site involvement.

• Ensure the documentation specifies "multiple sites" or lists several affected joints to support this code.
• Do not use this code for localized PVNS; instead, use the appropriate site-specific code from the M12.2- category.
• Confirm the "pigmented" aspect of the synovitis is documented, as non-pigmented villonodular synovitis is a distinct condition.