A bone marrow biopsy is a procedure that collects samples of the spongy tissue found inside certain large bones. This soft tissue, called bone marrow, is responsible for producing the body’s red blood cells, white blood cells, and platelets. Physicians order this test primarily to examine the health of the blood cell factory and to diagnose or monitor conditions affecting the blood and marrow. The resulting samples provide detailed information about blood cell production, cellular morphology, and potential abnormalities unavailable through standard blood tests.
Preparing for the Procedure
Before the procedure, review all current medications with your doctor, paying particular attention to blood thinners like aspirin or anticoagulants. These medications may increase the risk of bleeding and may need to be temporarily paused or adjusted before the biopsy. Inform your healthcare team of any known allergies, especially to lidocaine or antiseptic solutions used during the procedure.
If the procedure involves sedation, you will likely be asked to stop eating and drinking for a specific period before your appointment. If only local anesthesia is used, you can typically eat a light meal beforehand to help prevent lightheadedness. Wear comfortable, loose-fitting clothing, ideally a two-piece outfit, that allows easy access to the hip area.
Since mild sedation or the local anesthetic can cause drowsiness, arrange for a trusted person to drive you home after the procedure. This step is necessary for safety, particularly if you received any form of sedative.
What to Expect During the Biopsy
The procedure typically takes about 10 to 20 minutes, with most of the time spent on preparation and local anesthesia. The most common collection site is the posterior iliac crest, which is the back ridge of the hip bone. You will be asked to lie on your stomach or side, and the area will be cleaned with an antiseptic solution.
A local anesthetic is then injected into the skin and down to the surface of the bone to numb the area. This injection may cause a brief stinging or burning sensation before the area becomes numb. The procedure involves two main parts, often performed through the same small incision.
Bone Marrow Aspiration
The first part is the bone marrow aspiration, where a thin, hollow needle is inserted into the bone to withdraw a sample of the liquid portion of the marrow. When the liquid is suctioned, patients often feel a brief, sharp stinging sensation.
Trephine Biopsy
The second part is the trephine biopsy, which involves using a slightly larger needle to remove a small, solid core of bone tissue with the marrow inside.
During the trephine biopsy, you will feel a strong pushing and pressure as the needle is rotated into the bone to collect the sample. While the anesthetic minimizes sharp pain, the pressure sensation can be intense. The entire sample collection process is quick, and the healthcare team will encourage you to remain as still as possible until the needles are removed.
Immediate Post-Procedure Care and Recovery
Immediately after the needle is withdrawn, the clinician will apply firm pressure to the biopsy site for several minutes to stop any bleeding. Once controlled, a sterile dressing will be placed over the small wound. If you had only local anesthesia, you may be asked to lie flat for 10 to 15 minutes before being discharged.
Keep the bandage clean and dry for the first 24 hours to prevent infection. During this time, avoid showering, bathing, swimming, or using a hot tub. After 24 hours, you may shower, but avoid soaking the area until 48 hours have passed.
Soreness and bruising at the biopsy site are common and may last for several days. You can typically manage this discomfort with over-the-counter pain relievers, such as acetaminophen. For the first 24 to 48 hours, you must avoid strenuous activity, heavy lifting, or any exercise that puts strain on the hip area.
Contact your doctor immediately if you experience warning signs, such as bleeding that soaks through the bandage and does not stop after 15 minutes of direct pressure. Other concerning symptoms include a persistent fever, increasing redness, spreading swelling, or unusual drainage from the site. New numbness or tingling in the leg or foot on the side of the procedure also warrants an immediate call.
Understanding Your Results
After the samples are collected, they are sent to a specialized laboratory for analysis. A pathologist or hematopathologist specializing in blood diseases will examine the samples under a microscope. This analysis involves looking at the quantity and appearance of the blood cells and checking for abnormal cells.
The time it takes to receive the results can vary, typically ranging from a few days to a week. If the samples require highly specialized tests, such as genetic or molecular analyses, the final results may take up to three weeks. These specialized tests provide information essential for accurate diagnosis and treatment planning.
Your ordering physician or specialist will communicate the results and interpret the findings for you. Since the information obtained is often complex, a follow-up consultation is necessary to fully understand the implications of the biopsy. This allows the doctor to explain the findings and discuss the next steps in your care.