Osteogenic Cell Viability in Bone Graft Obtained Using the Reamer Irrigator Aspirator (RIA) System Versus Iliac Crest Bone Graft

Although iliac crest bone grafting is the gold standard for autogenous bone grafting procedures, limited quantity in some individuals and donor site morbidity have lead surgeons to look for alternative harvest sites or sources such as allograft or osteobiologics. Of these alternative harvest sites is the femoral shaft. Intramedullary contents from reaming are composed of bone marrow, and blood and bone spicules. In this respect, the reamed contents are similar to the bone routinely harvested from the iliac crest. Studies have shown that despite the reaming process using standard reamers, cells maintain their viability and are able to produce new bone. However, the addition of aspiration and irrigation used in the RIA system could potentially compromise the harvested cell viability and limit their osteogenic potential. In addition, Wenisch et al. have concluded that the harvested cells using standard intramedullary reamers not only proceed toward osteogenic differentiation, but also can be directed toward neurogenic differentiation. This suggests that reaming debris is a viable source of stem cells as well. RIA allows for these cells to be harvested. It is our hypothesis that the intramedullary contents harvested using the RIA system is similar to ICBG in cell viability and osteogenic potential.