I was in so much pain that I was rendered unable to walk 5 km. Coming from being able to do sprint triathlons, this was unimaginable!! Dr Wong in Halifax said that he would never perform a total knee replacement to a 45 year old woman. I am therefore on the wait list for Platelet Rich Blood Replacement, however, in the mean time he suggested durolane injection x3. I had a total of one injection which was three times strength and the results were amazing!! Withing one week I could sleep paing free, after two I could bike 30 km and after a month I could run 4 km!! I can have these injections every 6 months and they have no side affects!! I can't tell you how much these injections have given me a qualitiy of life!!