Tacoma General trapped me in the room when my son has his done So I can tell you the whole process..

First, they will inject a long need into the area, usually left side around hip. Please make sure it is numbed up before they add another longer needle into same spot. That right there will make the difference if you feel anything or the pain is intense. Give the medicine a few minutes to absorb, since most want to do this in and out and move to next patient. Make them make sure you are numbed up.

Then they put in another needle. Thicker. Then another needle goes into that needle and once they have made contact with a bone, it is almost like a very miniature cork screw that the tech will turn until he gets part of your bone. You should not feel this. It only takes a few minutes to get a sample. Then the tech will pull out the first needle and see if he got sample, usually a good little chunk of your bone. He will put it in a closed container to not expose it.

Then they will take the other needle out, put a bit of pressure on you to make sure no bleeding, then you are okay. There really are no restrictions, but don't go out and do heavy anything, I would totally recommend taking it easy for a day or two. They should have the results. My son has done 3 and there is no definitive answers. He has ITP. Losing platelets. Started with using a blood thinner, eliquis. Hope they find the answer. Hope this helped some. It's always more anxious when we psyche ourselves up to procedures. But once, they came in and took a bone marrow when my son was in the hospital and coming in unexpected, they were in and out and he felt nothing. That tech took the time to make sure he was numb. I can't express that enough. Make sure you are not feeling anything.