Localized vs Diffuse Villonogular Sinovitis

Pigmented villinogular sinovitis is caused by an over expression of the c s f on gene. Over expression leads to clusters of abarent cells creating focal areas of soft tissue hyper plasia in the senovial cells lining the joints. Diffuse p v n s most commonly seen in the knee, then the hip, then the ankle. Localized pevans is seen in a painless, swollen and tender joint with limited mobility.