Sometimes it is good to get away on vacation, which is why I didn’t have a new post for the Blog last week. Not only did I get a break from the routine, but the god for post topics smiled on me and a paper entitled “Autologous bone marrow concentrate intradiscal injection for the treatment of degenerative disc disease with three-year follow-up” was published in International Orthopedics just as I was returning to work. So, I didn’t have to think too hard about what to write about for this week’s post.
I need to point out that I am a co-author on the paper, but I left my previous employer 11 months ago when I joined Greyledge Technologies last September. So, my views are not independent, nor am I suggesting to a physician that they consider using BMC to treat degenerative disc disease, since I try not to tell docs how to practice medicine. Consequently, I will stick to the main points on the data shown in the paper and conclusions published therein; conclusions endorsed by the lead author and PI on the clinical investigation, Dr. Kenneth Pettine.
By way of background, I participated in drafting the BMC-treatment of degenerative disc disease clinical study that subsequently was approved by an IRB and initiated by Dr. Pettine and his clinical research staff back in 2013. My ex-employer donated the bone marrow aspirate processing device kits. A small aliquot of concentrated bone marrow (BMC) was obtained at the time of treatment and shipped to my ex-employer’s research laboratory for nucleated cell analysis; specifically, to provide an estimate of the number of what are popularly referred to as MSCs (mesenchymal stem cells) and to perform flow cytometric analysis to assess levels of several types or sub-types of stem cells, including CD34+ cells, a large share of which are hemopoietic stem cells (HSCs).
The focus of the pilot clinical study was to assess the safety and feasibility of injecting a patient’s own BMC into a pathologic lumbar disc. While that seems like a risky procedure, various types of fluids had been injected into discs over the years, but not BMC. I remember discussing with Dr. Pettine the potential downsides of this type of procedure. However, he pointed out that his proposed protocol essentially was a variation on a commonly employed procedure known as provocative discography.
One of the known adverse events associated with injecting discs reported in the literature is that the patient has a low, but non-zero chance of ending up with an infected disc. However, an advantage of injecting BMC is that it is loaded with anti-microbial cells (macrophages, granulocytes and their precursors), which would be able to attack any inadvertently introduced microbial contamination. This anti-microbial property of BMC isn’t mimicked by other fluids that are being injected, like fibrin-containing preparations. So, Dr. Pettine was comfortable that the BMC injection itself wouldn’t be as risky as injecting other fluids into the disc.
There was a total of 26 patients enrolled in the study, with 13 patients being treated at a single lumbar disc and 13 patients being treated at two adjacent lumbar discs, giving a total of 39 discs treated. Dr. Pettine believed it was important to include 2-level disc patients, citing the frequency of 2-level patients appearing in his waiting room. I, on the other hand, was concerned that these patients would have twice the opportunity to drop out. As I will discuss in the next post, there is good reason sometimes not to listen to a PhD in clinical matters.