Zippy
Went to Sloan Kettering for a 2nd opinion. The outcome is that there is nothing but surgery to do for a recurring PVNS. If it get very bad, they will replace your knee and clean outas much of the growth as possible. The doctor said you can never get it all out so if came back once, it can come back again. Radiation is not recommended because it can turn a benign growth into a cancer. The Yttrium has not been used with very much success and it is only used by one doctor in Boston. If you've had a knee replacement and the growht gets so bad, you have to have the replacement replaced (revision). The worst of all is amputation but the doctor I saw said it is very rare. There are 19 cases at the Mayo Clinic only 2 have had amputation.