Home › Blog › Ask Dr. C – Episode 1

As promised in yesterday’s blog, I was going to begin highlighting several of the questions I get each week, focusing on those I hear quite a bit from patients. So this is “Episode 1” of that service. Let’s dig in.

Question #1 from Randy-Do you ever recommend not trying stem cell or PRP treatment for knee osteoarthritis & instead recommend knee replacement?

First, the research we have to date for PRP and stem cells to treat knee osteoarthritis shows that they are likely appropriate for different severity levels of arthritis. Before we get there, some definitions. PRP means “Platelet Rich Plasma” which is when the doctor takes your blood platelets and concentrates them. “Stem Cells” in my discussion below is using your own bone marrow aspirate from which the doctor concentrates the stem cell fraction (aka bone marrow concentrate).

For example, most of the research to date on PRP (except for a single study), shows that it tends to work the best in mild to early moderate knee arthritis. That’s consistent with our experience as well. You can get more effects, in our experience, by going very high on the platelet concentration. What I mean by that is that 99% of doctors use bedside machines to make PRP and the highest those generally go is about seven times above baseline blood platelet concentration (7X). When I say “very high” I mean double to triple that concentration so 14X to 20X.

In our experience and based on our published data to date, the outcomes of stem cell procedures are much less dependent on the severity of the knee arthritis. Meaning patients with severe knee arthritis tend to do about the same as patients with mild knee arthritis. We’ve published this data in research papers and we are almost done with yet another publication to better identify if we can pick out those patients who should be told to avoid the procedure due to a high likelihood of failure. That paper will likely be submitted for publication later this year.

Hence, is there a severity level where we would steer the patient clear of a knee stem cell procedure? While we haven’t formally identified anyone based on severity who does more poorly, these are some things that would give me pause:

• Severe malalignment – The most common is a valgus deformity where the leg is significantly side bent.
• Severe extension lag and/or flexion contracture at the hip – This means that the knee can’t fully extend and the hip doesn’t straighten all the way.
• Severe displacement of the bones – The most common issue here is that the femur and tibia are no longer aligned side to side.
• Central sensitization – This means that the patient is so severely pain-sensitive that even small things like a massage cause a significant flare-up in their pain.
• Severe synovitis – This means that the lining of the inside of the joint called the synovium is extremely inflamed.

All of these would cause me to lower my estimate of how likely the procedure is to be effective.

Question #2-My question is regarding PRP booster shots after a successful Stem Cell treatment in one knee & successful PRP treatment in the other knee. At what point should I consider additional PRP injections? Should I get them with slight pain to stay on top of the healing or should I wait until really necessary?

Great question Barb! Let’s say that you had a successful stem cell procedure in your knee, at what point should you pull the trigger on a PRP booster shot? First, let’s review the “booster shot” concept.

On average, successful stem cell procedures in the knee for patients with severe arthritis, last for about 2-7 years. In our experience, some patients can extend that time frame with a high-dose PRP “booster shot”. This is usually a 14-20X (ultra-high dose) PRP injection just at the moment that symptoms begin to return. In my experience, these shots work better than waiting until the symptoms are bad again. Hence, early is better than later.

What does the PRP booster shot do? A stem cell injection for severe knee arthritis doesn’t regrow your cartilage and give you a brand new knee, despite what the Charlatan clinics claim with faked x-rays. The effect of decreased pain and increased function happens for other reasons which likely include:

• Healing damaged bone. These days we are injecting the damaged bone with stem cells as well as the joint. The goal is to heal small areas where wear and tear has damaged the microstructure of the bone. For example, there are now two randomized controlled trials that show that injecting the bone can prolong the results of a bone marrow knee stem cell procedure beyond the above discussed 2-7 years.
• Replacing the worn-out “stem cell reserve”. Arthritic knees have fewer native stem cells than their normal counterparts. By injecting stem cells into the knee, we hope to replace the lost stem cells which help with tissue maintenance needed when wear and tear occurs. Remember that mesenchymal stem cells are the “repairmen” of the body.
• Rebooting the toxic witches’ brew of chemicals within the knee. An arthritic knee has a slew of toxic chemicals that cause more tissue breakdown (catabolism). Our goal is always to move that chemical environment from pro-breakdown to pro-repair.
• Rescuing dying cells. Mesenchymal stem cells have been shown to be able to rescue dying cells. For example, they can give their good batteries (mitochondria) to cells with a dead battery to reboot the electrical system of the dying cells.

So what does a “booster shot” do? We believe it acts as an espresso shot for the stem cells we put into your joint at the initial procedure as well as other repair cells in the joint. It may help those cells to do some of the things I have reviewed above.

The upshot? Thanks for submitting your questions to my first episode of “Ask Dr. C”. As I said, I’ll try to write these long-form answers every week, so please keep leaving your questions in the blog comment section!

Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile