What Causes Burning Sensation In The Knees After A Knee Surgery?

Hello, I recently had knee surgery the end of Feb, 2017..my mri indicated a tear on exterior and interior of my meniscus. ..I am 50 yrs old, this was my 3rd surgery on that knee, last was 20 yrs ago...Everything was going great, had a weekly work out program and was gaining strength. ..then about a month after the surgery while moving around asleep in bed, i felt a pop and a burning feeling. ..woke up that morning and as soon as i put weight on it, it began to swell...I have had a history of gout, so i treated it like I was having an attack..10 days went by and it got worse. I was painful to put weight on it, when i tried to walk, it would give out on me..So i went back to my Orthopedic, we did another MRI, results showed where I once had cartilage, it was now gone...I don t want cortisone shots, or oil....My Dr said its ready to be replaced. ..however we opt to do another scope...My Question is am I wasting my time, should I just get it replace????...