It seems that very few TKR problems mention knees buckling. My knees have buckled on me since I was a kid. At 70 I thought I better do something about this because I am going to fall and really hurt myself so I had TKR done Feb of 23. A few weeks after it my right knee buckled and I fell. I told the surgeon and he had no answers except that its healing. All told my knees have buckled on me five times since my surgery and in April I fractured my femur. That surgeon got into a cumbersome brace but it did keep me upright and I have not buckled since may. My femur is healing nicely. My right leg is feeling stronger and I am back at the gym and swimming. My rom is probably 100 but I am petrified to put all my weight on my right leg i.e. going up and esp down stairs, Luckily we have no stairs where I live. I would like to hear from others who have TKR with a history of knees buckling.