@cls1 - I do get about 8 weeks of relief from cortisone. Both orthopedic docs said that there is too much risk with knee replacement in my case. I also have drop foot but wear orthotics which help but tend to trip at times going up steps, foot doesn't clear the step and land on knee. It involves weighing out the danger of bone damage if I were to fall with a replacement vs. keeping me the best they can pain free. In my case, it's a balancing act.