Overview
BMAC therapy harvests stem cells and growth factors from the patient's own bone marrow. The aspirate is concentrated and injected into damaged joints or tissues, providing a rich source of mesenchymal stem cells.
In-Depth: BMAC
Bone marrow aspirate concentrate (BMAC) is an autologous regenerative treatment, meaning it uses the patient's own biological material. The procedure involves extracting a small amount of bone marrow — typically from the posterior iliac crest (the back of the hip bone) — using a specialized needle under local anesthesia. The bone marrow aspirate is then placed in a centrifuge to concentrate the mesenchymal stem cells (MSCs), hematopoietic stem cells, growth factors, and other regenerative components into a much smaller volume. This concentrated product is then injected directly into the damaged joint, tendon, or tissue, usually under ultrasound or fluoroscopic guidance to ensure precise placement.
BMAC is considered one of the more evidence-supported stem cell treatments in orthopedic medicine. Bone marrow is a rich source of mesenchymal stem cells, which have the ability to differentiate into cartilage, bone, and other connective tissue cells under the right conditions. In addition to MSCs, bone marrow concentrate contains platelets, growth factors, and anti-inflammatory cytokines that work together to create a regenerative environment at the treatment site. The theory is that this combination of cells and signaling molecules can reduce inflammation, slow tissue degeneration, and potentially stimulate some degree of tissue repair.
Because BMAC is a same-day, minimally manipulated autologous procedure — meaning the cells are harvested, processed, and re-injected during a single office visit without being cultured or significantly altered — it generally falls within the FDA's guidelines for the practice of medicine. This regulatory distinction is important, as it means BMAC can be offered by qualified physicians without requiring the same level of FDA approval that would be needed for manufactured or expanded cell products. However, patients should understand that the FDA has not specifically approved BMAC for treating any particular condition, and its use is considered off-label.
How It Works
- 1 Bone marrow is aspirated from the posterior iliac crest (hip) under local anesthesia
- 2 The aspirate is processed in a centrifuge to concentrate stem cells
- 3 The concentrated bone marrow is injected into the treatment area
- 4 Imaging guidance ensures precise placement
- 5 Stem cells work to reduce inflammation and promote repair
Best For
Risks & Side Effects
- Pain and soreness at the bone marrow harvest site, which typically lasts three to five days
- Temporary increase in pain at the treated joint or tissue
- Small risk of infection at the harvest or injection site
- Bruising and stiffness at the hip where marrow was extracted
- Rare risk of nerve damage during bone marrow aspiration
- No guarantee of treatment success — stem cell count and quality vary between patients and with age
Who Is a Good Candidate?
- Good candidates: Patients with mild to moderate osteoarthritis, meniscus tears, or tendon injuries who want to try regenerative treatment before considering surgery
- Good candidates: Younger patients tend to have higher stem cell counts in their bone marrow, potentially improving outcomes
- Good candidates: Patients who prefer using their own biological material rather than donor tissue
- May not be ideal: Patients with severe bone-on-bone arthritis, as the degree of damage may be too advanced for biological repair
- May not be ideal: Patients with bone marrow disorders, certain blood cancers, or who are on medications that affect bone marrow function