What Is Bone Marrow Aspirate Concentrate (BMAC)?

Bone Marrow Aspirate Concentrate (BMAC) is prepared by aspirating marrow—commonly from the iliac crest—and concentrating it at the point of care before injection into a selected musculoskeletal target. The final product contains plasma, platelets, red and white cells, mononuclear cells, hematopoietic cells, and a small, variable number of stromal progenitor cells.

Not a purified stem-cell dose

Calling BMAC “millions of stem cells” can be misleading unless validated methods characterize the final product. BMAC is not culture-expanded mesenchymal stromal cells, and cell counts, viability, colony-forming assays, platelet concentration, and red-cell content vary by aspiration and device.

Evidence

Studies investigate BMAC for knee osteoarthritis, cartilage lesions, tendon or bone conditions, and surgical augmentation. Some report pain or function improvement, but protocols and comparators vary, and evidence does not establish predictable cartilage regrowth or superiority over less invasive options. FDA states no stem-cell products are approved for orthopedic conditions.

Two procedures, two risk sets

Marrow harvest adds pain, bleeding, infection, anesthesia, and donor-site injury. The target injection adds joint, tendon, nerve, vascular, or other anatomy-specific risks. Imaging guidance and rehabilitation matter as much as the centrifuge brand.

Product questions

Ask about aspiration site and volume, number and size of draws, anticoagulant, processing device, final volume, cell characterization, additives, sterility, same-day handling, imaging guidance, evidence, and regulatory basis.