What happens on the day of a procedure?

What happens before anything begins?

First, staff must tell you who will do each part. The person examining your joint then reviews the procedure with you.

The form must name what will enter your body. It can't leave out where that liquid will go.

Ask whether you'll stay awake or get medicine that makes you sleepy. The answer affects food, driving and your time afterward.

Don't stop a blood thinner yourself. The doctor responsible for that medicine must approve a change.

Tell the clinic about fever, recent antibiotics or a new illness. The clinic can't safely proceed during an infection.

What is taken from the bone near my hip?

Marrow is the soft tissue inside your bones. A hollow needle draws some from the pelvic bone behind your hip.

You may feel pressure, pulling or a short sharp feeling. Numbing medicine helps, but it can't remove every feeling.

The clinic spins the sample to separate it, much like dressing settling into layers. The person doing the procedure keeps a thicker layer containing blood and cells.

A needle then delivers the liquid to the joint or nearby tissue chosen beforehand. Ask the person to point to the exact spot first.

Your hip and joint may ease at different rates. Get care directions for both areas.

What do I need before I leave?

Get written directions for the bandage, bathing, driving and movement. Keep the after-hours phone number with those directions.

Ask how much soreness is normal and when to call. Don't test your joint while numbing medicine still hides the ache.

Call now for fever, leaking fluid or redness that spreads. Worsening pain, calf swelling, numbness or weakness also needs help.

Set up a firm chair and needed supplies before leaving home. You'll have an easier ride when everything is ready.

Sources

1. A retrospective comparison of 523 bone marrow aspiration procedures against 435 open iliac crest bone graft harvests found aspiration significantly reduced complications - relevant because marrow aspiration for a joint injection is a real procedure with a real, if low, complication rate.

   Hernigou P, et al. — Morbidity of graft harvesting versus bone marrow aspiration in cell regenerative therapy. Int Orthop, 2014. DOI: 10.1007/s00264-014-2318-x.

2. In 96 patients, concentrated bone marrow aspirate contained a mean of 26.3 million nucleated cells per mL but only about 1,422 colony-forming units of connective tissue progenitors, and the nucleated cell count had negligible predictive value for how many progenitor cells were actually present (r-squared 0.28).

   Muench LN, et al. — Nucleated Cell Count Has Negligible Predictive Value for the Number of Colony-Forming Units for Connective Tissue Progenitor Cells (Stem Cells) in Bone Marrow Aspirate Harvested From the Proximal Humerus During Arthroscopic Rotator Cuff Repair. Arthroscopy, 2021. DOI: 10.1016/j.arthro.2021.01.064.

3. Mesenchymal stromal cells make up only about 0.001 to 0.01 percent of the nucleated cells in bone marrow, so the harvesting and processing technique - aspiration site, syringe size, centrifuge speed and time - materially determines what ends up in the syringe, and no consensus protocol exists.

   Jeyaraman M, et al. — Impact of the Process Variables on the Yield of Mesenchymal Stromal Cells from Bone Marrow Aspirate Concentrate. Bioengineering (Basel), 2022. DOI: 10.3390/bioengineering9020057.

4. The 2018 AAOS/NIH consensus work group recommended that minimally manipulated mixed cell preparations be called CELL THERAPY rather than stem cell therapy, and that their untested and uncharacterised nature be clearly communicated to patients and the public, because stem cells have properties these preparations do not meet.

   Chu CR, et al. — Optimizing Clinical Use of Biologics in Orthopaedic Surgery: Consensus Recommendations From the 2018 AAOS/NIH U-13 Conference. J Am Acad Orthop Surg, 2019. DOI: 10.5435/JAAOS-D-18-00305.