The bone marrow biopsy is a mysterious and often feared procedure. This should not be the case. In reality, it is a very safe and important test that is usually associated with only minor pain and discomfort. The procedure is performed by a blood specialist (hematologist), usually to evaluate an abnormality of the blood counts: if the red blood cells, white blood cells or platelets are too high or too low or when a blood cancer is suspected (the three main types are leukemia, lymphoma and multiple myeloma). To learn about blood counts and blood cancers, please consult my book.
There are two parts to the procedure, the aspiration and the biopsy. The most important part, however, is the preparation. [Caution: stay off other internet websites that scare the dickens out of people about this procedure!] The patient is made to expose the hip areas (lower pants and underwear to just above the knees) and to either lie on their side or flat on their stomach. The doc then sterilizes the skin over the area of the bone called the iliac crest (top of the ilium or hip bone); this will feel wet. Then he/she will inject a little lidocaine under the skin, which smarts (like getting that first novacaine injection by the dentist). Then a longer needle is passed under the skin to the outer surface of the iliac crest and this area is generously injected with lidocaine; this usually does not hurt and the patients feels only numbness wthen the doc probes with a sharp needle. Once this important preparation is done, the rest should go easily for the patient and the hematologist.
Next, the aspiration is performed. The doc will insert a special aspiration needle into the bone, just under the surface, to penetrate the squishy innter marrow. He/she will then suck out a few cc's of liquid marrow into a syringe; this will feel weird and sometimes can be painful for a few seconds. Once the liquid marrow is obtained, the aspiration needles is withdrawn. The liquid is divided into three portions: 1) Spread on a slide to analyze the individual marrow cells; 2) Sent for genetic/DNA analysis; and 3) Sent for flow cytometry. Please consult Fighting Cancer with Knowledge and Hope to learn more about these tests.
Finally, a longer needle which has an inner trochar surrounded by an outer hollow shell is inserted into the bone. The doc will first penetrate the outer bone and remove the inner trochar. He/she will then twist and turn the hollow "coring" needle and apply gentle pressure to go in about 2-3 centimeters. The biopsy specimen is inside this needle and once the pushing stops, the doc will grip the specimen by the flip of a switch on the needle (or other method depending on the kit) and remove the entire apparatus. The patient experiences a strange sensation during this portion of the procedure; sometimes there is a moment of sharp pain but often there is not. Once the doc is done, the assistant will clean and dress the hole (smaller than a pencil eraser) and the patient is usually asked to rest for a few minutes to allow the stress of the procedure to pass.
That's all there is to it! Though not pleasant, the bone marrow biopsy is safe, important and usually performed in 15 minutes (allow an hour for preparation before and rest afterwards).