I re-read your message. So please confirm, you did NOT have the knee replacement surgery?
The Iovera is meant to last a minimum of 3 months. However, I have talked to several people that said theirs lasted quite a bit longer.
The feeling of a 'wooden leg' after the treatment is designed to sharply minimize the pain you would have felt right after surgery (if you had not had the Iovera) & also thru the painful rehab process.
I still have extreme tightness (like a tourniquet or band) around my knee cap.
Await your reply!