Villonodular synovitis (pigmented), left ankle and foot

This code signifies a benign, proliferative synovial lesion characterized by villous and nodular growth, often with hemosiderin deposition (pigmented), affecting the left ankle and foot. It represents a localized form of tenosynovial giant cell tumor, which can cause pain, swelling, and limited joint movement.

Use this code when documentation explicitly states a diagnosis of pigmented villonodular synovitis (PVNS) or giant cell tumor of the tendon sheath (GCTTS) specifically located in the left ankle or foot. Supporting documentation includes pathology reports confirming PVNS/GCTTS, imaging findings consistent with the condition, and physician notes detailing the anatomical site.

• Ensure the laterality (left) and anatomical site (ankle and foot) are clearly documented to support this specific code.
• Distinguish from other inflammatory or neoplastic synovial conditions; a definitive diagnosis, often via biopsy, is crucial.
• Do not use for diffuse PVNS, which has different coding assignments.