Research has demonstrated that the number of fibroblast-like colony forming units (CFU-f) in a graft is positively correlated with clinical outcomes. Cells capable of forming a CFU-f are found in marrow but not in blood and therefore are an indication of the number of early stage stem and progenitor cells present in a biologic. Several systems are available for harvesting autologous bone marrow aspirate and optionally centrifuging it to further concentrate cells, via volume reduction, to treat local bone defects.