Study On Osteanagenesis And Revascularization Of Tissue Engineered Bone Accelerated By Pedicle Deep Fascia Flap In Vivo (Caprine)

[Objective]Based on the success of repairing the weight-bearing bone defect of small animal and non weight-bearing bone defect of big animal with tissue engineered bone,we want to further study whether tissue engineered bone can repair the large segment bone defect of large animal or not. Then we prepared an experimental caprine model of tibia bone defect ready for the next experiment,studied the tissue engineered bone's ability of repairing 2cm defect of weight-bearing bone of caprine,and it's revascularization process. Also we observed what character the fascia flap played during this process.[Methods]1. 9 Chinese caprine were chosen for this experiment. The 2cm left tibia diaphyseal defect of every caprine was made,and fixed with plate. Bone regeneration and blood supply were evaluated by ECT,X-ray and histology.2. 27 caprine were divided into three groups:group A (the defect was filled with coral hydroxyapatite CHAP);group B (the defect was filled with CHAP + bone marrow stroma cell BMSc);group C (the defect was filled with CHAP +BMSc + fascia flap). After finished culturing and inducing the BMSc,CHAP of group A and B were combined with it. The caprine were made of 2cm bone defect fixed with 93mm AO dynamic compression plate of levo-tibia,then were implanted with different material as described above separately. Radionuclide bone imaging was used to monitor the revascularization of the implants at 2 4 8 weeks after operation. X-ray examination,optical density index of X-ray film,V-G staining of tissue slice of the implants were used at 4 8 12 weeks after operation and the biomechanics of the specimens tested at 12 weeks postoperation were the main way to evaluate the bone regeneration and-4-the effect of repairing the defect. VG staining of histology was ideal method to judge the revascularization of implants.[Results ]1. In the first study,the numbers of ROI and the ratio of T/NT showed no bone regeneration and revascularization. The Lane's scores of nine caprine were all zero. There was no osteanagenesis found in tissue slice. By the observations of these ways the defect showed no bone regeneration phenomenon.2. In the second study,group A manifested a little trace of bone regeneration,as to group B,the defect was almost repaired. In group C,with the assistance of fascia flap which gave more chance to making implants to get more nutrient,the repair was quite complete. The turn of the osteanagenesis and revascularization from wore to less was group C,B,A. We also found that fascia flap can accelerate the osteanagenesis of tissue engineered bone by the mean of accelerating the revascularization.[Conclusion]1. The model of 2cm Caprine tibia diaphyseal defect cannot be repaired by Caprine itself and was suitable for the next experiment.2. Tissue engineered bone had good ability to repair large segment tibia defect of Caprine.3. Fascia flap can accelerate the revascularization process of tissue engineered bone. And by this way,it augment the ability of tissue engineered bone to repair the large bone defect of caprine.