What are Stem Cells or Bone Marrow Aspirate Concentrate (BMAC)?

Stem cells are immature precursor cells that are very helpful in promoting tissue healing and regeneration. Stem cells, also known as Mesenchymal Stem Cells or Medicinal Signaling Cells (MSCs), are most abundant in bone marrow and adipose tissue (fat). These cells have the ability to differentiate into many types of tissue (cartilage, muscle, tendon, etc.). Additionally, stem cells can act as helper cells that actively drive the body’s natural healing process. Placing high concentrations of these stem cells in an anatomic area of injury is the therapeutic goal of this treatment strategy.


Bone Marrow Aspirate Concentrate (BMAC)

How are BMAC or stem cells obtained?

Stem cells derived from bone marrow are obtained by inserting a large-bore needle into the intramedullary space of the iliac crest (hip bone). This procedure is typically done under anesthesia and is a simple needle puncture. The aspirated blood is then centrifuged to concentrate the growth factors and healing agents. This preparation, called bone marrow aspirate concentrate (BMAC), can be used effectively in a myriad of clinical circumstances.

Who should consider BMAC as a treatment option?

Best candidates for the use of BMAC treatment are patients with the following conditions:

  • Tendinopathy (tennis elbow, golfer’s elbow, patellar tendinopathy, jumper’s knee)
  • Ligament injuries
  • BMAC can also be used an adjunct to cartilage repair procedures (osteochondral allograft, osteochondral autograft, chondroplasty).
  • BMAC is also sometimes used as a supplement therapy for patients with osteoarthritis.

Studies Supporting BMAC – Bone Marrow Aspirate Concentrate:

Knee cartilage injury, arthritis, joint inflammation:

Rodriguez-Fontan et al. Phys Med Rehab (PMR) 2018. 10(12):1353-1359.


Pascarella et al. Am J Sports Med. 2011 39(9):1975-83. Thornton et al. Am J Sports Med. 2005 33(10):1558-1564. 

Rotator Cuff and Meniscus Repair:

Kim et al. J Orthop Surg Res. 2018. 3;13(1).Koch et al. Int J Mol Sci. 2019. 5;20(5).

For more information about bone marrow aspirate concentrate (BMAC) and how orthopedic conditions can be treated with innovative regenerative biologic medicine, please contact the office of Riley J. Williams, MD, orthopedic knee surgeon serving Manhattan, Brooklyn, New York City, NY and surrounding areas.  


HSS Sports Medicine Institute West Side
610 W 58th Street
New York, NY 10019

HSS Brooklyn
148 39th Street, 7th Floor
Brooklyn, NY 11232

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Fax: 212-774-2895