Experiment Of Heterologous Bone Enriched Autologous Bone Marrow Cells Combining With Autologous Bone Marrow Gel To Promote Spine Fusion In Rabbits

Objective :To observe the fusion rate of using heterologous bone enriched autologous bone marrow cells combining with autologous bone marrow gel to do lumbar posterolateral intertransverse fusion surgery in rabbits,and then provide a simple, fast and effective clinical research way for increasing spinal fusion rate.Methods :Twenty-four New Zealand white rabbits were randomized into four treatment groups (n=6 per group):Group A, heterologous bone enriched autologous bone marrow cells combining with autologous bone marrow gel, Group B,heterologous bone saturated autologous bone marrow, Group C,heterologous bone saturated saline, Group D,iliac crest autograft, each group materials were implanted on both sides of L3/4, L4/5 or L4/5,L5/6 transverse process in each group. At 12 weeks postsurgery,all animals were sacrificed by air embolism, collecting the spine (lumbar spine) specimens, which removed the soft tissue,and then gross,manual palpation,X-ray examination,CT scan reconstruction,biomechanical testing and histological detection were performed to analyze spinal fusion.Results :At 12 weeks postsurgery,the gross observation showed that the implant site in group A was fusion and the fusion bone was larger than group B,C. However, the implant site in group B,C were partly fusion and the fusion bone were smaller than group A. There had no significant difference on Single segment fusion bone between group D and group A. The fusion rate of group A, B, C, D were 91.7%, 41.7%, 16.7%, 100%.There had significant difference on fusion rate between group A and group B (P=0.027<0.05). There had significant difference on fusion rate between group A and group C (P=0.001<0.05). There had no significant difference on fusion rate between group A and group D (P=1.0>0.05).Conclusions :This experiment investigated a cell enrichment technology which was possible in the operating room and didn't require cell culture conditions. Autologous bone marrow was aspirated before surgery, added to a research and development machine pre-filled with about human cancellous bone particles to concentrate autologous bone marrow and obtain human cancellous bone particles enriched autologous bone marrow cells. At the same time, autologous bone marrow gel was prepared and combined with human cancellous bone particles enriched autologous bone marrow cells. The composite graft was obtained and then was implanted in the spine transverse process. It was found that there had no significant difference on spinal fusion rate between heterologous bone enriched autologous bone marrow cells combining with autologous bone marrow gel group and iliac crest autograft group. However,it was better than the rest of the control groups. This will be a simple, fast and effective clinical way for increasing spinal fusion rate.