A bone marrow biopsy (BMB) collects and examines samples of the soft, spongy tissue inside certain bones where blood cells are produced. This test is performed to investigate the health of the blood-making system or when an abnormal blood count is detected. Physicians use the BMB to diagnose conditions like anemias, infections, and cancers, including leukemia, lymphoma, and multiple myeloma. The procedure also helps determine if a known cancer has spread or monitors a patient’s response to treatment.
Managing Discomfort and Sensation During the Biopsy
Modern techniques minimize discomfort during a BMB using local anesthesia, such as lidocaine. This agent is injected into the skin and down to the bone surface to numb the area. The initial injection causes a brief stinging or burning sensation that quickly fades as the numbing agent takes effect.
Although the anesthetic blocks sharp pain, patients still feel pressure as the needle passes through the dense outer layer of bone. The local anesthetic does not eliminate the sensation of pressure or movement within the bone. Patients may also receive a mild sedative through an intravenous (IV) line to help them relax, especially if they are anxious.
The most distinct part is the bone marrow aspiration, which uses a syringe to suction the liquid marrow sample. This suction creates a momentary vacuum inside the bone cavity. Many describe this as a sharp, deep, or pulling sensation that may radiate down the leg. Although intense, this feeling is typically very brief, lasting only a few seconds while the sample is withdrawn.
The second part, the core biopsy, uses a slightly larger needle to collect a solid cylinder of bone tissue. During this step, patients primarily feel a strong, dull pressure as the needle is rotated to capture the sample. Since the area is already anesthetized, the discomfort during the core biopsy is generally less sharp than the aspiration phase.
Step-by-Step Guide to the Biopsy Procedure
The bone marrow biopsy is typically an outpatient procedure lasting 20 to 30 minutes. The sample is most commonly taken from the posterior iliac crest, which is the back of the hip bone. The patient is positioned on their side or lying face down to provide easy access to this site.
Once positioned, the medical team cleanses the skin over the site with an antiseptic solution, which may feel cold. A local anesthetic is then injected down to the bone surface to numb the surrounding tissue. A small incision may be made to allow for easier passage of the biopsy needles.
The first sample collected is the liquid part, known as the bone marrow aspiration. A thin, hollow needle is inserted into the marrow cavity, and a syringe draws out a small volume of fluid.
Following aspiration, a separate, slightly larger hollow needle is inserted through the same puncture site to obtain the solid tissue sample (the core biopsy). This specialized needle is advanced and rotated to cut out a small, intact piece of bone marrow. Once both samples are secured, the needle is removed, and firm pressure is immediately applied to the site to control bleeding.
Preparing for and Immediate Recovery After the Procedure
Preparation involves considering medications that affect blood clotting. Patients must inform their doctor about all prescription and over-the-counter medicines, including blood thinners, aspirin, and supplements, as some may need to be temporarily stopped. If sedation is used, patients are instructed not to eat or drink for several hours beforehand, often starting after midnight.
Arrangements must be made for transportation home, especially if sedation is administered, as the medication impairs driving ability. After sample collection, the medical staff applies pressure to the puncture site until bleeding stops. A sterile dressing is then applied to the wound.
Patients who received only local anesthesia are asked to lie flat for 10 to 15 minutes to continue applying pressure. Those who received IV sedation spend 30 to 60 minutes in a recovery area for monitoring. The dressing must be kept dry for the next 24 hours, meaning showering, bathing, and swimming must be avoided.
For the first 24 to 48 hours, patients should avoid strenuous activity, heavy lifting, or movements that strain the site. Soreness or bruising is common and can be managed with over-the-counter pain relievers, such as acetaminophen, as recommended. Patients should contact their healthcare provider immediately if they experience excessive bleeding that soaks through the bandage, a persistent fever, or increasing pain, swelling, or drainage at the site.