Bone Marrow Aspiration · What Is It, How It’s Done, and More

Bone marrow is the soft, spongy tissue found mainly within long bones, vertebrae, and pelvic bones. Individuals are born with only red bone marrow, which is primarily found in the ribs, sternum, scapula, clavicle, skull, and spine. As individuals age, about half of the red bone marrow is replaced by yellow bone marrow. Red bone marrow contains hematopoietic stem cells, which are undifferentiated cells that have the potential to differentiate into various specialized cell types (e.g., red blood cells, white blood cells, and platelets). Red blood cells are responsible for carrying oxygen to tissues in the body, white blood cells help fight infection, and platelets assist with blood clotting. On the other hand, yellow bone marrow primarily consists of fat, which can be used for energy production. It also contains mesenchymal stem cells that can develop into fat, cartilage, or bone cells if needed. 

Bone marrow contains both solid and liquid components. Liquid bone marrow contains the stem cells and makes vitamins for cell production, while solid bone marrow is a dense tissue crucial for blood formation. Certain illnesses and treatments can dest

A bone marrow aspiration and biopsy are two different medical procedures often performed consecutively to diagnose blood and bone marrow disorders by examining the composition of bone marrow and identifying any abnormalities in bone marrow cells. They are also used to collect bone marrow samples for medical procedures, such as stem cell transplant or chromosomal analysis.  

The primary purpose of a bone marrow aspiration is to identify the types of cells present in the bone marrow sample and assess their characteristics. Similarly, the primary purpose of a bone marrow biopsy is to identify conditions affecting the blood and bone marrow, such as blood cancers and bone marrow disorders. Both procedures are collectively known as bone marrow examinations and are often conducted on the hip or pelvic bones as these areas contain a significant amount of red bone marrow, are easily accessible, minimize discomfort, and provide reliable diagnostic samples. 

 A bone marrow aspiration involves the removal of liquid bone marrow. During this procedure, a small, hollow needle is used to collect a sample of the liquid portion of the bone marrow. It’s a relatively quick procedure, spanning a few minutes, and is often performed immediately prior to a bone marrow biopsy, although it may also be performed alone.   

On the other hand, a bone marrow biopsy involves the removal of a solid piece of bone marrow tissue. During this procedure, a larger needle is used to remove a small amount of bone marrow tissue and takes around 30 minutes to perform. It’s often done immediately after a bone marrow aspiration, although it may also be performed alone. 

After completion of a bone marrow aspiration and/or bone marrow biopsy, a specialist (i.e., pathologist) will examine the bone marrow cells under a microscope and communicate results through a pathology report. 

A bone marrow aspiration is typically performed by a hematologist, oncologist, or trained advanced practice healthcare provider such as a nurse practitioner or physician assistant in a hospital or clinic setting.  

Prior to the procedure, a healthcare provider will gather detailed information about the individual including medical history (e.g., bleeding disorders such as hemophilia), medications (e.g., blood thinners such as aspirin), allergies, and pregnancy status. An individual will also be counseled on any necessary preparations, such as fasting and medication holding, what to expect during the procedure, and post-procedure care. The individual undergoing the procedure will then be asked to sign a consent form. 

During the procedure, the individual may change into a hospital gown, and if necessary, receive a sedative such as lorazepam to help with relaxation. The individual typically lies on their side or prone, for ease of access to the most targeted site for the procedure (i.e., hip bone). The healthcare provider will clean the skin with an antiseptic, numb the area with a local anesthetic such as lidocaine, and make a small incision at the site. A hollow needle is then inserted into the bone to perform a bone marrow aspiration. An individual may experience some discomfort during the procedure, such as a sharp stinging sensation, which may be managed with medications such as ibuprofen or acetaminophen. After the bone marrow sample is collected, the healthcare provider will remove the needle, exert pressure on the area to stop any bleeding, and apply a bandage or dressing over the wound. The collected bone marrow sample is then sent to a laboratory for examination.  

After the procedure, individuals may typically be discharged home the same day, and if sedation is received, they may be asked to secure a ride home. Individuals may be advised to take non-prescription pain relievers such as acetaminophen or ibuprofen, avoid strenuous physical activity for at least 24 hours after the procedure, keep the wound dry for a specific amount of time, monitor for any signs of infection, and report any unusual symptoms or severe pain.  

A bone marrow biopsy follows a similar pre- and post-procedure process as bone marrow aspiration, with a key difference involving a larger needle to collect a core sample of solid bone marrow tissue. During this time, an individual may experience pressure, pain, and discomfort as bone cannot be numbed and has an extensive supply of sensory nerves. 

The risks of bone marrow aspiration may involve bleeding, bruising, redness, swelling, tenderness, pain, and discomfort at the biopsy site. Complications such as prolonged, excessive bleeding or infection of the skin at the biopsy site may also occur. In rare scenarios, injury to the heart, lung, or a major blood vessel may occur if a bone marrow sample is collected from the sternum. 

The benefits of bone marrow aspiration involve accurate diagnosis of various blood disorders, cancers, and genetic diseases; effective disease staging, treatment monitoring, and guidance strategies; donor matching for stem cell transplants; and advancement of medical research.