Comparison of sternal, iliac, and humeral bone marrow aspiration in Beagle dogs

Background Sternal bone marrow aspiration in dogs is not commonly performed as it is considered technically challenging in smaller dogs. However, the sternum is readily accessible and associated with less pain from aspiration compared with other sites. Objectives The aim of the study was to investigate feasibility, ease, number of attempts, safety, and sample quality of sternal bone marrow aspirates in small dogs. Methods Bone marrow aspirates were obtained in a randomized order from 3 sites in 26 clinically healthy Beagles under general anesthesia. Samples were obtained from the sternum using one-inch 20- or 22-gauge hypodermic needles, from the right greater tubercle of the humerus, and the right iliac crest using 18-gauge Illinois needles. The difficulty of each procedure was scored. Two types of bone marrow smears were prepared and reviewed by a pathologist unaware of site of aspiration or dog. The number of particles per slide and overall slide quality were scored. The site of aspiration and the cranial thoracic wall were evaluated at autopsy for evidence of trauma or pneumothorax. Results The number of attempts and time for bone marrow aspiration were greater for ilium than for sternum or humerus, but the sternum was the easiest to aspirate. Smear quality and particle number were similar for all sites. Neither trauma at the site of aspiration nor pneumothorax were identified. Conclusions Aspiration of sternal bone marrow with hypodermic needles is feasible and safe in Beagle dogs. Samples equivalent in quality to those from the humerus or ilium can be obtained from clinically normal dogs.