Cartilage Regeneration: Origins & Research

Origins of Biologic Augmented Microdrilling (BAM)

Dr. Khay Yong Saw and his research team in Kuala Lumpur, Malaysia have been studying stem cell cartilage regeneration for several years. Dr. Saw's protocol involves microdrilling surgery followed by weekly post-operative injections of autologous peripheral blood progenitor cells (PBPC's) and hyaluronic acid (HA).

  • Microdrilling Surgery is an arthroscopic outpatient surgery where small holes are drilled in the bone at the location of cartilage damage. This procedure is a marrow stimulating technique performed to provide an environment for cartilage healing by mobilizing local bone marrow derived stem cells to the site of the cartilage lesion.
  • PBPC's are a blood product containing mesenchymal stem cells, the stem cells capable of differentiating into normal cartilage. PBPC's are obtained by mobilizing stem cells from bone marrow into the peripheral blood.
  • Hyaluronic acid is a building block for cartilage in the knee. It been shown to improve pain when injected into knees of patients with cartilage damage. HA injections have also been used in animal studies to generate better cartilage after microdrilling surgery.

Dr. Saw and his team propose that the microdrilling surgery creates a blood clot scaffold on which injected stem cells can be recruited and enhance normal cartilage regrowth. The significance of this cartilage regeneration protocol is that it is successful in patients with historically difficult-to-treat bone-on-bone cartilage damage. To date, Dr. Saw has treated approximately 400 patients with this technique. He has published both a case series and a randomized clinical trial on this treatment. 

Dr. Broyles Goes to Malaysia

Cartilage Regeneration ResearchSince first learning about Dr. Saw's cartilage treatment, Dr. Broyles has made several trips to Malaysia to study the techniques and protocol used by Dr. Saw's research team. Dr. Saw and Dr. Broyles have operated together at the Kuala Lumpur Sports Medicine Center (pictured), and were interviewed by a Malaysian newspaper during one of his trips. Read the full article.

Knee Cartilage Regeneration Research at the Bone & Joint Clinic

Building off of Dr. Saw's methods and some of his own cartilage regeneration research, Dr. Broyles collaborated with local Hematologist/Oncologist Dr. Patrick Stagg, to design and execute a stem cell cartilage clinical trial at the Bone and Joint Clinic of Baton Rouge.

The main difference between Dr. Broyles’ BAM procedure and Dr. Saw’s treatment is that Dr. Broyles uses fresh Bone Marrow Aspirate Concentrate (BMAC) and Platelet Rich Plasma (PRP) in each post-operative injection in addition to Hyaluronic Acid (HA). The reason for this modification is two-fold – First, in the US, the FDA regulates PBSC’s as a ‘drug’ and mandates that their use in the knee needs to go through their Investigational New Drug application procedure. This process is arduous and expensive. Second, there is growing evidence supporting the use of BMAC and PRP to augment microdrilling and cartilage cell growth.

  • BMAC has a higher percentage of mesenchymal stem cells than mobilized peripheral blood, and the stem cells in bone marrow divide more times before quitting.[1] Also, bone marrow concentrate has been used in numerous animal studies to improve regenerated cartilage compared to microfracture alone.[2], [3]
  • PRP has been shown in multiple studies to promote mesenchymal stem cell differentiation into and proliferation of cartilage cells.[4]  Separately, it has also been shown to improve regenerated cartilage compared to microfracture alone.[5]


Early results of Dr. Broyles’ BAM case series show encouraging imaging, pain and function results. See publications and read our patient testimonials for individual patient results.

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[1]   Lund TC, Tolar J, and Orchard PJ. Granulocyte colony-stimulating factor mobilized CFU-F can be found in the peripheral blood but have limited expansion potential. Haematologica 2008; 93:908-912.

[2]   Fortier LA, Potter HG, Rickey EJ, et al. Concentrated Bone Marrow Aspirate Improves Full-Thickness Cartilage Repair Compared with Microfracture in the Equine Model. Journal of Bone and Joint Surgery 2010; 92:1927-37.

[3]  Saw KY et al. Articular Cartilage Regeneration With Autologous Marrow Aspirate and Hyaluronic Acid: An Experimental Study in a Goat Model. Arthroscopy 2009;25:1391-1400.

[4]  Allan Mishra, M.D., Padmaja Tummala, M.S.,  Aaron King, B.S., M.B.A., Byung Lee, B.S., Mark Kraus, M.D., Victor Tse, M.D., Ph.D., and Christopher R. Jacobs, Ph.D. Buffered Platelet-Rich Plasma Enhances Mesenchymal Stem Cell Proliferation and Chondrogenic Differentiation. Tissue Engineering, 2009, 15(3): 431-435.

[5]   Milano G, Sanna Passino E, Deriu L, Careddu G, Manunta L, Manunta A, Saccomanno MF, Fabbriciani C.  The effect of platelet rich plasma combined with microfractures on the treatment of chondral defects: an experimental study in a sheep model.  Osteoarthritis Cartilage. 2010 Jul;18(7):971-80.