Technique of Bone Marrow Aspiration
What you need to know about your anatomy before Bone Marrow Aspiration
At birth, all bones contain hematopoietic marrow. Fat cells begin to replace hemopoietic marrow in the extremities in the fifth to seventh year. By adulthood, the hemopoietic marrow is limited to the axial skeleton and the proximal portions of the extremities. Fatty marrow appears yellow, whereas hematopoietic marrow is red. Red marrow contains fat, however, and fat droplets are visible grossly in aspirated marrow specimens. Histologically, yellow marrow consists almost entirely of fat cells and supporting connective tissue. Red marrow contains an abundance of hemopoietic cells, fat cells, and connective tissue. The marrow fills the spaces between the trabeculae of bone in the marrow cavity. Marrow is soft and friable and can be readily aspirated or biopsied with a needle.
Best places for Bone Marrow Aspiration
The posterior iliac crest is the preferred site for bone marrow aspiration and biopsy. In adults, the sternum and the anterior iliac crest also can be used . The sternum should be used for aspiration only. The anterior iliac crest is less preferred than the posterior crest in adults because of the crest’s thick cortical bone. The anteromedial surface of the tibia is an option for infants younger than 1 year old (particularly newborns), but the posterior iliac crest is still the preferred site. The spinous processes of the vertebrae, the ribs, or other marrow containing bones are rarely used.
Complications after Bone Marrow Aspiration
Serious adverse outcomes after bone marrow aspiration or biopsy are rare, less than 0.05 percent. In this study one direct fatality, and three episodes of prolonged but not permanent disability were observed in nearly 55,000 bone marrow biopsies. Morbidity most frequently involved hemorrhage, which were associated more with platelet function impairment than thrombocytopenia or coagulation factor defects. Infection and reactions to anesthetic agents are other infrequent complications. Penetration of the bone with damage to the underlying structures is possible with all bone marrow aspirations, but the hazard is greatest in sternal aspirations because the sternum at the second interspace is only approximately 1 cm thick in adults. To prevent this, a guard should be in place on the needle when a sternal aspirate is done.