That Duke study is very positive.  Within the next 10 years we should be real improvement in cartilage regeneration as a viable alternative to knee replacement so long as the patient is not "bone on bone" already.

Now to report on my progress to date with TissueGene-C (TG-C):

I go in for my 18-month review of the TissueGene-C injection next week.  Overall I am very pleased with the results.  My ability to use my left knee has increased since my last exam six months ago.  I can perform some exercises involving the knee that I could not half a year ago and that I was no way able to do before I received the injection.  I haven't had to go in for any hyaluronic acid injections in the knee for the past 8 months and feel no need to do so now.  I used to have to get them every 6 months.

My biggest problem has been discovering that I have numerous bone spurs in the left knee joint that really limit doing anything "extreme" with the knee.  I attribute these spurs to the microfracture procedure performed on the knee about 4.5 years ago.  I knew within months after that procedure that I had developed a bone spur on the lateral side of the knee.  But it was not until the most recent X-ray of my left knee that we saw the other bone spurs in the joint.  When I first was examined to see whether I qualified for the TissueGene-C study 18 months ago, one couldn't see squat regarding lateral side of this knee--it looked like a cloud bank blotting everything out.  I assume that was the second-class cartilage that had been created by the microfracture procedure.  But a year later, we got a much clearer X-ray--which was additional proof to me that the TissueGene-C substance had done a lot to replace the weak second-class cartilage with real articular cartilage.  But that clearer image also disclosed the bone spurs lurking there.

Unfortunately the Korean product can't resolve bone spurs.  I may have them for life.  I've been doing a lot more swimming as a cardiovascular workout and very little cycling over the past 6 months.  But cartilage wise, that knee is much improved.

The latest press release by the U.S. company handling the FDA study is at http://www.tissuegene.com/news/releases.html.  They seem to be making slow but steady progress toward getting FDA approval for single-injection use of the product.  My understanding is that they want that ASAP to get some initial return on investment while they forge ahead with testing of multiple-injection trials that will likely begin sometime later this year.  Enrollment in the Phase II study is now closed.  Your best bet is to wait till they announce the Phase III study and volunteer, though I assume 1/3 of the participants in that may receive a placebo, just as was done for the Phase II.  But maybe not.

I'll have to check through this KneeGeeks site to see if there are any good approaches to removing bone spurs, but the little I've heard thus far does not make me optimistic.     But that's a secondary concern compared to my knee arthritis over the past decade.  So overall, I'm in a good frame of mind.