Autologous Implantation of Bone Marrow for Non-Unions and Avascular Necrosis of the Bone.

Introduction: Autologous implantation of bone marrow (BM) stem cells for avascular necrosis of the bone has been previously demonstrated to be feasible and safe procedure. The benefit of using autologous stem cells for bone regeneration consists of avoidance of graft rejection, graft-versus-host disease, and the toxic and infectious complications associated with immunosuppressive regimens.

Materials and Methods: We developed an efficient protocol to process autologous BM for volume reduction and mononuclear cell concentration that can be immediately used for autologous implantation. The end-product is a concentrated BM cell suspension that was defined by several parameters as follows: volume, mononuclear cell count, CD34-positive cell count. A total of five patients under general anesthesia underwent BM aspiration, followed by immediate intraoperative BM concentration and implantation at the injured site. Four patients had avascular necrosis of the bone and one had tibia non-union. The patients were followed for one year and monitored clinically and by imaging studies.

Results: All five patients treated with autologous bone marrow implantation at the avascular necrosis or non-union site tolerated the procedure well. One year follow-up of these patients reveals improved clinical and functional status. The imaging performed pre and one-year-post procedure revealed no evidence of bone collapse and preserved joint space.

Conclusions: Autologous implantation of concentrated bone marrow is a safe and promising treatment for non-unions and avascular necrosis of the bone. Additional studies for further characterization of the concentrated BM used for implantation are in progress.