Commentary & Perspective

Commentary & Perspective on
"Aspiration of Osteoprogenitor Cells for Augmenting Spinal Fusion: Comparison of Progenitor Cell Concentrations from the Vertebral Body and Iliac Crest"
by Robert F. McLain, MD, et al.

Commentary & Perspective by
Alexander R. Vaccaro, MD*,
The Rothman Institute, Philadelphia, Pennsylvania

Several tissues serve as potential hematopoietic reservoirs for connective tissue progenitor cells. Until recently, it was thought that the richest source of useful nucleated stem cells was the cancellous bone of the iliac crest (with lesser amounts found in the femur and tibia), but the iliac crest presents certain difficulties as a reliable donor source.

Accessing the posterior iliac crest during an anterior spinal procedure may mean repositioning the patient at the time of bone marrow aspiration if the anterior crest is deemed unsuitable due to small size or inadequate sample source. Also, patients may have substantial pain at the iliac-crest harvest site after spinal decompression and fusion even though they have had relief from radicular pain. Therefore, it has become desirable to obtain stem cells from a site that is in closer proximity to the fusion procedure—that is, the vertebral body. The authors of this paper have undertaken a well-performed study that has shed considerable light on the usefulness of the vertebral body as a source of osteoprogenitor cells. They found that the vertebral body had an equal or greater prevalence and concentration (71% higher) of nucleated osteoprogenitor and connective tissue progenitor cells when compared with the iliac crest. Thus, a surgeon may successfully harvest precursor cells at the site of surgery rather than subject the patient to harvesting from a distant surgical site.

During the sequence of preparing a pedicle for screw insertion, the surgeon can now aspirate a defined amount of bone-marrow aspirate prior to placement of instrumentation. It is extremely satisfying that the authors noted equal or greater amounts of osteoprogenitor cells regardless of the vertebral body level, the age of the patient, the gender of the patient, or the depth of aspiration.

Spine surgeons will have the opportunity to easily access a source of autologous osteoprogenitor cells, thus avoiding the potential for immune rejection and also avoiding the cost of recombinant or synthetic osteoinductive materials.

*The author did not receive grants or outside funding in support of his research for or preparation of this manuscript. He did not receive payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. No commercial entity paid or directed, or agreed to pay or direct, any benefits to any research fund, foundation, educational institution, or other charitable or nonprofit organization with which the author is affiliated or associated.

Copyright © 2005 by the The Journal of Bone and Joint Surgery, Inc.