I've just completed imaging after my third round of pentosan...

I've just completed imaging after my third round of pentosan injections so its time for an update.

To recap, 56 yo male, I sought pentosan treatment for arthritis of the lower spine. I had a great response and my OA disappeared, for about 9 months. So I had a second course of treatment at the 12 month mark. At the 2 year mark I was still feeling great, no OA pain, but I went ahead with a third treatment anyway, as a preventative measure. You can read all about this in my earlier posts in this thread.

I got MRIs before the start of treatment, after the 2nd treatment, and after the third treatment. I timed the post treatment MRIs to ~56 days after treatment, consistent with PAR's trials showing greatest effect. As related above, they showed really quite remarkable resolution of bone marrow oedema (bone bruising), which is thought to be a large part of arthritic pain.

So on to the latest results, after the third treatment. The boring version is that things are stable. There were dramatic changes from before treatment to after the 2nd treatment, but the 3rd set of images look pretty similar to the 2nd. This is good - no change and preserving the effects of the second course out another year. And I feel great - I'm writing this just home from 2 hours hard training, jujitsu, kickboxing drills and a grappling session. So I remain very mobile through my spine.

So I wanted to show another feature of my imaging that I haven't talked about before. I have (or perhaps had, see below) facet joint osteoarthritis. The facet joints are where the spiny parts of the vertebrae rest on each other. The facets have a layer of cartilage, which in my case of severe, stage 4, OA of the L4/L5 and L3/L4 facet joints, especially on my right side, had worn away. No cartilage.

Here's a picture pointing out the relevant facet joints so you can see what I'm talking about:



Now take a look at the images for L4/L5. Remember dark is more dense tissue like bone, light is less dense like water, nerves or cartilage:



Look at the right facet joint, before treatment, indicated by the arrow. There is no cartilage here. It's basically bone on bone. It's a very degenerated joint. But, after treatment, and continuing to today, there is dramatic restoration to a much healthier joint structure, indicated by the bright line. This is joint space widening, which I believe is a structural marker PAR will use to show DMOAD.

The question is, what is filling the space in the joint? It can't be just fluid, these are load bearing joints and fluid alone won't hold them apart. It has to be some form of hydrogel, like a crosslinked hyaluronic acid, or polyglycoside. Or, dare I say it, cartilage? I never hoped for that but its consistent with the imaging.

To show that its not a fluke, the same story repeats going up a vertebrae to L3/L4:



This level was perhaps not quite as bad as L4/L5, but it was still pretty gnarly to start with. Possibly some cartilage, possibly not. MRI doesn't have the resolution to see. But a dramatic improvement seen after two treatments, and still holding up today. Either regrowth or at least expansion of cartilage.

Obviously I'm delighted with the results. The functional improvement follows the imaging and I'm really happy with the outcome. But the structural changes are amazing to see. Would I say my disease has been modified? Absolutely. Really looking forward to Paradigm taking this out to everyone suffering from this disease.