Bone marrow aspiration
Bone marrow is the soft tissue inside bones that helps form blood cells. It is found in the hollow part of most bones. Bone marrow aspiration is the removal of a small amount of this tissue in liquid form for examination.
Iliac crest tap; Sternal tap
How the Test is Performed
Bone marrow aspiration may be done in the health care provider's office or in a hospital. The bone marrow will be removed from your pelvic or breast bone. Occasionally, another bone is selected.
The health care provider will clean the skin and apply a numbing medicine (local anesthesia) to the area and surface of the bone. Next, a special needle is inserted into the bone. The needle has a tube attached to it, which creates suction. A small sample of bone marrow fluid flows into the tube. The needle is removed.
A laboratory specialist looks at the bone marrow fluid under a microscope.
How to Prepare for the Test
Tell the health care provider:
- If you are allergic to any medications
- If you are pregnant
- If you have bleeding problems
- What medications you are taking
You must sign a consent form for the procedure.
How the Test Will Feel
You will feel a sting and slight burning sensation when the numbing medicine is applied. You may feel pressure as the needle is inserted into the bone, and a sharp and sometimes painful sucking sensation as the marrow is removed. This feeling lasts for only a few moments.
On rare occasions, patients are given medicine to help them relax.
Why the Test is Performed
Your doctor may order this test if you have abnormal types or numbers of red or white blood cells or platelets on a complete blood count. This test is used to diagnose:
- Anemia (some types)
- Other blood disorders
It may help determine whether cancers have spread or responded to treatment.
The bone marrow should contain the proper number and types of:
- Blood-forming (hematopoietic) cells
- Connective tissues
- Fat cells
What Abnormal Results Mean
Abnormal results may be due to:
- Acute lymphocytic leukemia (ALL)
- Acute myelogenous leukemia (AML)
- Chronic lymphocytic leukemia (CLL)
- Chronic myelogenous leukemia (CML)
- Disseminated bacterial or fungal infections
- Idiopathic thrombocytopenic purpura (ITP)
- Multiple myeloma
- Myelodysplastic syndrome (MDS)
- Primary thrombocytopenia
- Waldenstrom's macroglobulinemia
There may be some bleeding at the puncture site. More serious risks, such as serious bleeding or infection, are very rare.
This test is often performed when there are problems with various types of blood cells. The person may be at increased risk for bleeding, infection, or other problems.
Hoffman R, Benz EJ, Shattil SS, et al. Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2008.
Ohls RK, Christensen RD. Development of the hematopoietic system. In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap.446.
Quesenberry PJ. Hematopoiesis and hematopoietic growth factors. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier;2007:chap 160.
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.