Over the last couple of decades, I am sure that every time I have had the honor to teach or lecture at a symposium, I have always received much more knowledge, skills, insight or motivation than I have ever imparted. This was the case two weeks ago, when I had the honor of speaking and participating in live cases in Seoul, South Korea at the International Stem Cell Conference. More than 500 surgeons from South Korea attended; most were either plastic or orthopedic surgeons.
I had never been to South Korea before and was excited to have the opportunity to see and experience that country’s medical system. Interestingly, there was only one lecture dealing with a podiatric condition (mine), but what made the conference so good is that I got to listen to lectures dealing with the surgical techniques and science of harvesting autologous stem cells, their biologic activity and augmentation with autologous fat grafts.
I also got to hear the collateral intellectual chatter about what is happening on this front or that front with bone marrow aspirate concentrate (BMAC, Harvest Technologies). Trying to be as inconspicuous as a bird-masked reveler at a Mardi Gras festival, I spoke little but listened intently as I heard various captivating side discussions of the absolute miracles of this new medical technology.
Cardiac trials with BMAC are currently underway in the United States. There are also anecdotal cases in other countries with mind-blowing results with application of these autologous pleuripotential stem cells into hypoxic cardiomyopathic cells that are introduced through a stent. This results in the growing of new cardiac tissue.
Revascularization of distal extremities is occurring in patients with severe peripheral arterial disease (PAD), some of whom have previously failed peripheral bypass surgeries and were headed to certain below knee or above knee amputation.1 Avascular necrosis of the femoral head is successfully and routinely being treated with this technology and in a minimally invasive way.
Podiatric surgery is just now starting to get its proverbial big toe wet in this wonderful pool of miraculous bioscience. However, I will go out on a revascularized limb (pun intended) and say that within the next decade, all serious podiatric surgeons will be fully immersed in this primordial goo of bioengineering. They will have to be because patients are going to demand it.
While I have almost a decade of experience with autologous platelet concentrate (a.k.a. platelet rich plasma or PRP), I obviously have limited experience with BMAC in podiatric surgery due to it being such a new technology. However, I have seen incredible initial results with the treatment of osteochondral lesions of the talus with this technology. I look forward to more research in this area by our profession because we will be able in the near future to offer our patients results that are currently “out of reach.”
Think of BMAC as PRP on steroids. I am a huge proponent of the use of autologous platelet concentrate (APC) in the treatment of tendinopathy and plantar fasciopathy, which I have described previously.2 However, there is a whole different “animal” contained in this new concoction.
Remember that with PRP, there are many masqueraders out there hiding behind a mask of cacophonous bioscience babble. A couple of these have even infiltrated our ranks with claims of absolute nonsense. By definition, these new technologies cannot even be called PRP because they are nothing more than spun blood.
You need to look at the real science and what the patient is getting. What platelet yield and what coefficient of variance is there in the product you are going to deliver? You need to have a yield of at least a minimum of about 1 million platelets/µL. Be sure to look at the work of Kevy and Jacobson, who have compared the different systems out there for both PRP and bone marrow aspirate.3
Despite what the well coiffed, hot looking rep tells you over the free lunch, check out the facts about what systems deliver what and then make your decision. I can assure you that it will be an easy decision.
All bone formation (as well as tissue formation, which needs regenerative technology) is dependent on the recruitment of endothelial progenitor cells (EPC), hematopoietic stem cells (HSC), mesenchymal stem cells (MSC) and their supporting accessory cells to the defect site, total nucleated cells.
Iliac crest autograft is often considered the gold standard for bone grafting. The iliac crest contains bone marrow, which is a rich source of the regenerative cells needed for angiogenesis and optimal bone formation and healing. Iliac crest autograft includes:
Endothelial progenitor cells. The EPCs stimulate angiogenesis, release BMP-2, BMP-6 and upregulate the production of BMP-2.
Hematopoietic stem cells. The HSCs orchestrate bone formation and directly convert to stromal MSCs (CD34).
Mesenchymal stem cells. The MSCs convert to osteoblasts in support of new bone formation.
Platelets. Platelets mediate cell-to-cell adhesion through the release of various adhesion and growth factors such as SDF-1.
Lymphocytes. The lymphocytes support the migration and proliferation of EPCs.
Granulocytes. Granulocytes release vascular endothelial growth factors in support of angiogenesis.
Iliac crest autograft is a rich source of regenerative cells for bone formation. The harvesting of autograft, however, is not always practical, is traumatic, can be time consuming and is associated with significant morbidity in as many as 30 percent of the cases.4
The cellular compositions of autograft and concentrated nucleated cells from bone marrow aspirate are virtually equivalent and transplanting these concentrated regenerative cells in a scaffold mimics autograft.
It is now possible for the surgeon to conduct a marrow aspiration and concentrate the total nucleated cell load quickly (four to six times the baseline) in a minimally invasive fashion. This virtually eliminates graft harvest morbidity but provides the benefits associated with stem cells. Also remember that tibial marrow and calcaneal marrow do not measure up to iliac crest marrow, so have your orthopedic partners get this for you. You need the best for these dramatic miracles.
Bone marrow aspirate concentrate makes it possible to eliminate the need for autograft by efficiently concentrating and recovering regenerative cells while retaining their cellular viability and proliferative potential. The technology also concentrates all the key cells in their natural ratios, which is a very important factor. Finally, BMAC ensures cellular viability by retaining the cells in a natural microenvironment.
The surgeon can adjust cell dose/volume in less than 15 minutes in the OR. This produces a consistent and reliable nucleated cell load to aid in fusion or tissue regeneration.
I encourage everyone out there to start looking at this technology for those special cases in which this could be beneficial. Remember that you should reserve BMAC for those situations in which you really need biologic Superman. Also remember that PRP or APC are just your normal everyday superheroes successfully warding off enemies like “Tendinopathy Man.”
Editor’s note: Dr. Barrett is a member of the speaker’s bureau of Harvest Technologies, Inc.
1. Tateishi-Yuyama E, Matsubara H, Murohara T, et al. Therapeutic angiogenesis for patients with limb ischaemia by autologous transplantation of bone-marrow cells: a pilot study and a randomised controlled trial. Lancet. 2002; 360(9331):427-435.
2. Barrett SL, Erredge SE. Growth factors for chronic plantar fasciitis? Podiatry Today. 2004; 17(11):36-42.
3. Kevy S, Jacobson M. Comparison for methods of point of care preparation of autologous platelet gel. J Extra Corpor Technol. 2004; 36(1):28-35.
4. Acharya NK, Mahajan CV, Kumar RJ, Varma HK, Menon VK. Can iliac crest reconstruction reduce donor site morbidity? A study using degradable hydroxyapatite-bioactive glass ceramic composite. J Spinal Disord Tech. 2010; 23(4):266-271.