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To investigate the effectiveness of injectable tissue engineering to repair full-thickness meniscal defects.From June 2008 to February 2009 full-thickness of meniscal defects were created in the anterior corner of goats, which with no blood supply, in a diameter of 2 mm. Then bone marrow stem cells (BMSCs) was mixed with injectable calcium alginate gel to fill the defects. Other groups include the calcium alginate gel and empty group were served as control groups. At different time points, the animals were sacrificed and macroscopy, microscopy determination, electroscopy and MRI detection were performed to assess the outcomes of repairing.The meniscal defects had been filled thoroughly in 16 weeks after operation with white, tough and elastic repair tissue similar to normal meniscal fibrocartilage in the tissue engineering groups. The repair tissue was mainly fibrochondrocytes in line with the calcium alginate fiber. Thick matrix secreted by the cells crammed the space between fibers. The view under electroscopy demonstrated that the microstructure of the repair tissue was normal and cells were in a fibrocartilage phenotype.The full-thickness meniscal defects in regions without blood supply can be reconstructed effectively with injectable tissue engineering.

To introduce the biplanar opening high tibial osteotomy with rigid fixation for adult varus knee.Twelve patients with varus knee and degeneration of medial compartment received the biplanar opening high tibial osteotomy between June 2001 and July 2008. The pre-operative deformity was about 11.5 degrees without osteoarthritis changes in other compartments. The average range of motion was more than 90 degrees . One of the patients had ruptures of LCL and ACL, who received osteotomy after reconstruction of the ligaments. The main symptom before the operation was pain in medial compartment. The range of motion, Lysholm score and subjective satisfactory examinations were assessed before and after the osteotomy.All of the osteotomy sites were healed at twelve to sixteen weeks after operation. No complications such as plate broken or injury of nerve or blood vessel had occurred. The mean correct angle was 9.5 degrees . No degenerative changes had developed in other compartments of the knee. The mechanical axis of the lower extremities was maintained during the follow-up. The overall satisfactory rate was 83.3%. Statistically significant changes exist in the Lysholm score and varus degree.The open-wedge high tibial osteotomy is suitable for the symptomatic genu varum in younger patients with good short-term and mid-term results.

To investigate the effectiveness of human insulin-like growth factor I (hIGF-I) gene transferred into the cultured goat bone marrow mesenchymal stem cells with liposome, and find a new method of cell-mediated gene therapy.Bone marrow was extracted from adult goats and cultured in vitro by monolayer. Then the recombinant eukaryotic expression plasmid pIRES2-EGFP-hIGF was transfected into cells by FuGene 6. After transfection, the marker gene coding enhanced green fluorescent protein (EGFP) was observed at different time points. The hIGF concentration in the supernatant fluids was measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry stain of hIGF was performed to detect the target protein. Besides, reverse transcription polymerase chain reaction and flow cytometry were also adopted in order to find out the changes of cells after transfection.Bone marrow stem cells were all in the long shuttle-like shape and adhered to the disk. The expression of EGFP was first found at 4 h after transfection. The amount and intensity of EGFP increased gradually during the period of detection and got to the peak degree at 72 h, after that decreased slowly. EGFP was also seen in the second generation cells, but the intensity was relatively faint. The IGF-I concentration secreted into the supernatant was in accordance with the EGFP observed with the peak concentration at 34.75 ng/ml. The outcome of RT-PCR and immunohistochemistry was positive. The morphology of many stem cells was changed into triangular or irregular forms under the circumstance of the secreted hIGF-I. Percentage of stem cells in the S stage increased after transfection.The hIGF-I gene can be transfected efficiently and safely into BMSCs by FuGene 6, and the hIGF-I protein can be secreted into the supernatant in a relatively high level during a long period, therefore accelerate the proliferation and differentiation of the transfected cells.