BMAC — Bone Marrow Aspirate Concentrate

What It Is

Bone marrow aspirate concentrate, or BMAC, is an injection made from your own bone marrow. Marrow is drawn (aspirated) through a needle from the back of the pelvis under local anesthesia, then spun in a centrifuge to concentrate the cell population: mesenchymal cells, growth factors, and platelets. The concentrate is then injected, usually under ultrasound or fluoroscopic guidance, into the painful joint, tendon, or cartilage defect.

The biology is similar in spirit to PRP — both use the patient’s own healing factors — but BMAC adds bone-marrow-derived cells to the mix. It is considered an orthobiologic rather than a drug; nothing foreign is introduced.

At OSI, BMAC is performed in the operating room at CHRISTUS Outpatient Surgery Center. The OR setting allows safer aspiration, sterile concentration, and image-guided injection in a single short visit. Despite the OR location, this is a small, brief, minimally invasive procedure — it is grouped with our other non-operative options because the spirit of the treatment is to delay or avoid a formal surgical reconstruction.

Where It Fits in Care

BMAC sits between conservative care (physical therapy, bracing, anti-inflammatories, cortisone) and reconstructive surgery. A reasonable candidate has typically:

• Persistent pain in a joint, tendon, or cartilage focus that has not improved with a structured course of physical therapy.
• Imaging that supports a degenerative or partial-tear pattern rather than a clean structural defect needing repair.
• Tried PRP, viscosupplementation, or cortisone without lasting relief, OR is looking for an option that goes beyond those.
• A desire to avoid, or not yet be ready for, joint replacement or surgical reconstruction.

Conditions We Consider It For

• Knee, hip, or shoulder osteoarthritis — mild to moderate
• Chronic tendinopathy (rotator cuff, patellar, Achilles, gluteal)
• Focal cartilage defects in the knee or ankle
• Partial-thickness rotator cuff tears in selected patients

Whether BMAC is the right next step depends on your imaging, symptoms, prior treatments, and what you’re trying to get back to. Your surgeon at OSI will go through the trade-offs with you in clinic.

What to Expect

Aspiration takes only a few minutes from the back of the pelvis under local anesthesia and light sedation. The marrow is concentrated in the OR while you wait. The concentrate is then injected into the target site under image guidance. Most patients walk out the same day. Soreness at both the aspiration site and the injection site is normal for several days. Activity is gradually advanced once the soreness settles.

Like PRP, BMAC is generally not covered by insurance and is paid out of pocket. The fee, scheduling, and prep details are reviewed before you commit.

What the Evidence Says

BMAC is an emerging biologic. Trials are mixed for osteoarthritis, modestly favorable for some tendon and cartilage applications, and the technology continues to develop. We frame it honestly in clinic: this is a reasonable option for the right person, not a guaranteed result. If a structural problem actually needs surgery, BMAC won’t replace that — and we’ll say so.