Analysis of cell therapies used in clinical trials for the treatment of osteonecrosis of the femoral head: A Systematic Review of the literature

Abstract Background Osteonecrosis of the femoral head (ONFH) is associated with regional loss of cells within bone, often resulting in pain and mechanical collapse. The purpose of this systematic review was to analyze the cell-therapies used in clinical trials for the treatment of ONFH. Methods A systematic review on the use of cell-therapies for the treatment of ONFH was performed. 1,483 papers were screened. Eleven studies met the criteria to be included in this review. Cell-based therapies used were analyzed based on: cell sources, collection techniques, cell processing, qualitative and quantitative characterizations and delivery methods. Results Ten studies used bone marrow, and one study used blood as the cell source. Nine studies used freshly isolated tissue-derived nucleated cells from bone marrow: mixed bone marrow-derived nucleated cells, one study used mixed blood-derived nucleated cells, and one study used culture-expanded cells derived from BMA. Cell dose varied from 2 million to 3 billion cells. Qualitative cell characterization of injected cells using surface markers was done by five studies using CD34. Two of the studies assayed the cell population using a colony-forming-unit assay. Conclusion There is a lack of standardization with respect to the quantitative and qualitative characterization of methods for cell harvest, cell processing, and cell transplantation/delivery. Cell-therapy holds promise as a means of restoring local cell populations that are made deficient due to injury or disease. Standardization in the use of nomenclature, and quantitative and qualitative characterization of methods for cell-harvest, processing, and delivery of cell-based therapies is required. Level of Evidence III, Systematic Review