Bone Marrow Concentrate Injection Procedure: The 90-Minute Timeline from Harvest to Home

Patients considering bone marrow aspirate concentrate (BMAC) therapy often understand the science behind the treatment but find themselves wondering about something more immediate: what will the actual procedure feel like? This gap between clinical knowledge and experiential understanding can fuel unnecessary anxiety.

This comprehensive walkthrough serves as a mental rehearsal for procedure day, covering every phase from arrival to departure. The entire BMAC experience typically spans approximately 90 minutes and unfolds across three distinct phases: harvest from the hip, processing through centrifugation, and injection into the target area. Understanding the sensory experience at each stage transforms uncertainty into preparedness.

Pre-Procedure: The First 15 Minutes (Arrival and Preparation)

Upon arrival at the clinic, patients check in and complete final consent documentation. A clinical team member records vital signs and confirms medical history details, including verification that NSAIDs have been discontinued for the required period.

The positioning phase begins shortly after. Patients lie face-down or on their side to allow access to the posterior superior iliac spine—the bony prominence at the back of the hip where bone marrow will be harvested. This position may feel unfamiliar, but staff provide pillows and adjustments for comfort.

The procedural team introduces themselves and explains their roles. Patients meet the physician performing the harvest and injection, along with support staff managing equipment and monitoring comfort levels. This pre-procedure conversation offers a final opportunity to ask questions and discuss sedation options.

The sterile field setup becomes visible: drapes arranged around the hip area, ultrasound or fluoroscopy equipment positioned nearby. Patients feel the coolness of antiseptic solution being applied to the hip and hear the subtle sounds of instruments being prepared. These sensory details, while unfamiliar, signal that the team is following precise safety protocols.

Phase One: Bone Marrow Harvest from the Hip (Minutes 15-35)

The harvest phase begins with local anesthetic injection. Patients experience a brief sting as the numbing medication enters the skin, followed by a spreading warmth and then complete numbness in the area. This sensation is similar to dental anesthesia—momentarily uncomfortable, then remarkably effective.

A waiting period of three to five minutes allows the anesthesia to take full effect. The physician may engage in casual conversation during this time, which serves the dual purpose of distraction and continuous assessment of patient comfort.

When the aspiration needle is inserted, patients feel deep pressure rather than sharp pain. The sensation is often described as a dull pushing or reaching feeling—distinctly different from surface-level discomfort. The actual harvest involves extracting approximately 50-60 mL of bone marrow over 15-20 minutes.

During aspiration, patients may experience a deep, pulling sensation. This is normal and indicates the procedure is progressing correctly. The sounds during this phase include gentle suction and communication between the physician and staff. Patients should distinguish between pressure (expected and tolerable) and pain (which should be reported immediately for additional numbing).

Multiple small aspirations from slightly different angles yield better results than one large draw, as this technique preserves the concentration of stem cells and growth factors. Once complete, pressure is applied to the harvest site, and patients transition to sitting or lying on their back.

Phase Two: The Processing Interval (Minutes 35-55)

The extracted bone marrow now enters the centrifugation phase. The centrifuge spins the bone marrow at high speed, separating components by density. This process concentrates the mesenchymal stem cells (MSCs), growth factors, and anti-inflammatory cytokines into a therapeutic preparation.

This 20-minute processing window offers patients time to rest and hydrate. The hum of the centrifuge machine provides ambient background sound. Staff may offer a light snack or water, and patients can ask questions about the next phase.

Checking in on the harvest site during this interval is normal. Patients typically notice tenderness and awareness at the hip—expected sensations that should not include severe pain or excessive swelling.

Some clinics show patients the visual transformation: before processing, the sample appears as dark red bone marrow; after centrifugation, a distinct yellowish layer of concentrated cells becomes visible. This concentrated BMAC—typically 2-6 mL—contains the regenerative components that will be injected.

As processing nears completion, staff help patients reposition for the injection phase, which varies based on the treatment area (knee, shoulder, hip, or other joint).

Phase Three: The Injection (Minutes 55-75)

Repositioning depends on the specific treatment area. Knee injections may involve lying on the back with the knee slightly bent; shoulder injections may require sitting or lying on the opposite side. Staff ensure comfort before proceeding.

A second round of local anesthetic numbs the injection site—a sensation similar to the first numbing at the hip. The brief sting gives way to numbness within minutes.

Precision guidance is critical during this phase. Ultrasound or fluoroscopic imaging allows the physician to visualize the exact target area in real-time. Patients may see the monitor displaying their joint anatomy and watch as the needle approaches the treatment site. This imaging guidance ensures the concentrated BMAC reaches the precise location where regenerative effects are needed.

The injection itself takes only two to five minutes once positioning is complete. Patients typically feel coolness from the ultrasound gel, pressure from the probe, and a mild fullness sensation as the concentrate enters the joint space. The actual volume injected is small—typically 2-6 mL—so the sensation is subtle.

After needle removal, pressure is applied and a bandage placed over the injection site. Staff guide patients through gentle movements of the treated area to check for immediate reactions and distribute the concentrate within the joint.

Post-Procedure: The Final 15 Minutes (Recovery and Discharge)

A 10-15 minute observation period follows the injection. Patients rest while staff monitor for any immediate reactions. Soreness at both the harvest and injection sites is normal, as is mild lightheadedness from lying down for an extended period.

Getting dressed requires careful movement. Staff assist as needed, particularly with bending or reaching that might stress the harvest site.

Discharge instructions are delivered both verbally and in written form. The most critical instruction involves NSAIDs: ibuprofen, naproxen, and aspirin must be avoided for two weeks post-procedure, as these medications interfere with the inflammatory response necessary for healing. Acetaminophen (Tylenol) is permitted for pain management, along with ice application following a 20-minutes-on, 40-minutes-off protocol.

A driver is required for transportation home due to potential sedation effects and general comfort considerations. Most patients walk independently to the vehicle but appreciate assistance.

Follow-up appointments are typically scheduled for one to two weeks post-procedure to assess initial healing and address any concerns.

The First 48 Hours at Home: What to Expect

The first 24 hours involve managing soreness at both sites. The harvest site on the hip often feels more tender than the injection site initially. Sleep positioning matters—patients should avoid lying directly on the harvest site and may find placing a pillow between the knees helpful for comfort.

Ice application continues on the recommended protocol: 20 minutes on, 40 minutes off, for the first 48 hours. Light movement around the home is encouraged, but running, jumping, and impact activities are prohibited.

Warning signs requiring a call to the clinic include fever, severe swelling, intense pain that worsens rather than improves, or signs of infection at either site. These complications are rare but warrant immediate attention.

Most acute soreness resolves within two to three days. The emotional experience during this period involves managing expectations—visible improvement typically begins four to eight weeks post-procedure as the regenerative process unfolds.

What Patients Wish They Had Known: Practical Insights

Preparation significantly improves the procedure day experience. Wearing loose, comfortable clothing with an elastic waistband allows easy access to the hip harvest site. Eating a light meal two to three hours before the procedure prevents both empty-stomach discomfort and post-procedure nausea.

Bringing a small pillow for the car ride home cushions the hip during transit. Planning for 24 hours of assistance at home—particularly for reaching and bending tasks—reduces strain on both treatment sites.

Setting up a recovery space before the procedure streamlines the return home: ice packs prepared in the freezer, medications accessible, entertainment within reach, and comfortable seating arranged.

Most patients report that the procedure is less painful than anticipated but more involved than a simple injection. Understanding this balance helps calibrate expectations appropriately.

Managing Expectations: Pain vs. Pressure vs. Discomfort

Three distinct sensations characterize the BMAC experience. Pain refers to sharp, intolerable sensations that should be reported immediately for additional numbing. Pressure describes the dull, tolerable sensations that accompany needle insertion and aspiration. Discomfort encompasses the general awareness and mild sensations that do not require intervention.

Generous local anesthetic significantly reduces sensation, but complete numbness is not always achievable in deeper tissues. Patients should communicate openly if sensations exceed tolerable levels—additional numbing is readily available.

Anxiety amplifies physical sensations. Patients prone to procedural anxiety may benefit from optional sedation, which creates a relaxed, drowsy state without full unconsciousness. Most patients rate the overall procedure experience as three to four out of ten for discomfort—less invasive than surgery, more involved than a standard injection.

The Recovery Timeline: From Days to Months

Recovery unfolds across distinct phases. Days one through three involve acute soreness and swelling at both sites, managed through ice and rest. Physical therapy may begin around week one with gentle range-of-motion exercises.

Weeks two through four see gradual return to daily activities while continuing to avoid impact activities. The four-to-eight-week window is when most patients begin noticing functional improvements—reduced pain, improved mobility, and enhanced quality of life.

By months two and three, activity restrictions lift with medical clearance. Continued improvement occurs through months three to six as the regenerative process continues working at the cellular level.

The bone marrow harvested from the hip fully regenerates within four to six weeks, leaving no long-term depletion at the harvest site.

Conclusion

The 90-minute BMAC procedure follows a predictable, manageable timeline that most patients tolerate well. Understanding each phase—harvest pressure, processing wait, injection precision, and home recovery—transforms procedural anxiety into informed preparedness.

Individual experiences vary based on anatomy, pain tolerance, and anxiety levels, but the framework remains consistent across patients. The temporary discomfort of procedure day serves a long-term regenerative purpose, with benefits potentially lasting years.

Patients should discuss specific concerns with their provider before procedure day. Thousands of patients undergo BMAC successfully with minimal complications, and thorough preparation makes the experience even smoother.

Take the Next Step: Schedule a BMAC Consultation

Unicorn Bioscience offers comprehensive BMAC procedures at eight locations across Texas, Florida, and New York. All injections are performed with precision ultrasound or fluoroscopic guidance by an experienced team.

Same-day treatment is available for qualified candidates, and both virtual and in-person consultations provide opportunities to discuss specific conditions and candidacy. Personalized treatment planning considers injury type, inflammation levels, and individual health goals.

Contact Unicorn Bioscience at (737) 347-0446 to schedule a consultation and learn whether BMAC is the right regenerative option for orthopedic conditions.