About 4 1/2 yrs. ago, I had a partial knee replacement done due to bone on bone. I developed a blood clot after surgery and had a pulmonary embolism. Luckily, I was still in the hospital and was rescusitated by medical personnel. I started having more pain in the same knee about a year ago and had to stop my walking routine. I went to riding a bike, but last February, my knee hurt so much I had to stop that also. My hip also began to hurt and was keeping me awake, so I went to see another orthodpedic surgeon who said my partial knee was not stable and he would replace it with a total knee replacement. I am scheduled for surgery in about 6 weeks. Now, I am having second thoughts. My pain in my hip and knee seems to much less and I am now able to ride my bike again. Also, I am terrified of having another pulmonary embolism. I still have chronic pain (actually in both knees) from the osteoarthritis, but I am wondering if I should postpone the surgery for now. I also have atrial fibrillation and am afraid of all the surgery risks.  I have lasting effects from the first PE and I'm not sure what the risk of another would be - even if I would be put on blood thinners after surgery.   I would, however, like to be able to walk again for exercise. I just don't know what to do.  Are my concerns legitimate - or am I just scared?