A simple point worth considering: There is likely to be more research into osteoarthritis treatment in the next 5 years than there was in the last 15.
Money, that's why.
Multinational companies spend their research and development funds on areas most likely to produce a return on their investment. Easy problems are solved first, then more difficult problems are addressed in order of their market size. The good news for sufferers of osteoarthritis is that the large baby boomer population is reaching retirement age. The number of people with knee osteoarthritis is rising exponentially and with it potential profits for the company that comes up with a minimally invasive treatment that is effective for the majority of patients.
Stem cell research is one area showing a lot of promise in the treatment of many diseases. On top of the first human arthritis stem cell research in the UK, another study is looking at the ability of stem cells to repair meniscal tears - a common sporting injury that often leads to early onset osteoarthritis. Both of these studies are of limited size and both involve the surgical implantation of cells but they represent important steps on the path to the goal treatment of a simple injection that has major benefits (for more on this study, click here.)
Every year you are able to delay a knee replacement gives researchers more time to develop new treatments. This is why I am a big advocate of (essentially risk-free) delaying tactics such as weight loss, quads exercises, and unloader knee braces.