OBJECTIVE: To study the treatment efficacy of vascularized periosteum graft and bone filling material for long bone defect. METHODS: Forty young and forty adult rabbits were divided into four groups respectively according to the bone filling materials. A 3 cm long segment was removed from the middle part of the rabbit radius to make a bone defect model. The periosteum was reserved and restored to set up a vascularized tubulate periosteum graft. On the left side, autogenous bone graft, decalcified allograft, tricalcium phosphate, and hydroxyapatite were used to fill in the bone defect respectively; on the right side, no bone filling material was used as controls. The repairing effect of bone defect was evaluated by roentogenography, biomechanical, and histological methods. RESULTS: In young rabbits, bone defects on both sides healed in the 6th week after operation. The bending strength of radius in the tricalcium phosphate group and in the hydroxyapatite group were lower in the 12th week and there was significant difference when compared with autogenous bone graft group, decalcified allograft group and control group (P lt; 0.05). The repairing mechanism included intramembranous and endochondral ossification, and intramembranous ossification was prevalent. In the adult rabbits, the repairing rates of bone defect were 50% in the autogenous bone graft group, 40% in the decalcified allograft group, 30% in the tricalcium phosphate group and in the hydroxyapatite group and 42.5% in the control group, respectively. CONCLUSION: In young rabbits, large bone defect can be repaired with vascularized tubulate periosteum graft with or without the combining use of bone filling materials. The bone filling material which will be substituted slowly is disadvantageous to the recovery of bone strength. In adult rabbits, vascularized tubulate periosteum graft combined with bone filling materials can not repair the large bone defect effectively.
Objective To investigate the advance in the management of skeletal trauma of the extremities. Methods The literature at home and abroad was reviewed, and the research findings withclinical experience in the therapeutic methods for fracture of the extremities were summarized.Results The concept on fracture management was renewed, the minimally invasive surgery (MIS) was developed and popularized, the implantation was improved, the navigation technique with computerassisted surgery was applied, and the tissue engineering was developed. The fracture mana gement was changed from the anatomical reduction with absolutely rigid fixation to the biological osteosynthesis with protection of the fracture environment. The minimally invasive surgical techniques included the minimally invasive plate osteosynthesis, intramedullary nailing, external fixation, arthroscopic surgery,and computer-assisted surgery. In concordance with the MIS principles, the newimplants, such as the locking compression plate, and the less invasive stabilization system were well designed and put into clinical practice so as to provide effective therapeutic results in treating osteoporotic fractures and complicated articular and/or metaphyseal fractures. In treatment of the delayed union or nonunion offractures, more effective techniques were employed, including the application of bone substitutes, which are degradable and have properties of bone conduction and induction. In the repair of segmental defects of the long tubular bone, the bonetransport and the vascularized bone grafts could work well. The investigation of the bone engineering revealed its great potentiality.Conclusion Fracture of the extremities is a common problem and its management should emphasize the recovery of the extremity function of the patient in addition to emphasis on the replacement and fixation of the biological structures. The combination of bone engineering and microsurgery represents the development tendency inthis field.
Objective To explore the effects of the basic fibroblast growth factor（bFGF） gene transfection on the meniscal fibrochondrocytes with the reconstructed lentivirus and to observe the response of the meniscal fibrochondrocytes to the bFGF gene transfection. Methods The cultured meniscal fibrochondrocytes were isolated from the same 3-monthold New Zealand rabbit. The cultured first-generation meniscal fibrochondrocytes were divided into 3 groups:Group A (experimental group), Group B (control group), and Group C (blank group). Each group comprised the cells in a 24hole flask in which each hole contained 2×104 cells. At the confluence of 60%, the fibrochondrocytes in Group A were cultured with the reconstructed lentivirus carrying the bFGF gene. The fibrochondrocytes in Group B were cultured with the lentivirus carrying no bFGF gene. The fibrochondrocytes in Group C were cultured without any intervention. After 48 h, the cell cycle, the collagen synthesis ability, the expression of bFGF, and the cell proliferation ability in each group were investigated. Results In Group A, the bFGF expression of 870±60 pg/ml was detected in the cells 48 h afterthe co-culture; however, in Group B and Group C, no expression of bFGF was found. After the co-culture for 6 days, the results of the MTT colorimetry revealed that the cells in Group A had an absorbtance of 0.427±0.037, which had a significant difference when compared with that in Group B and Group C (0.320±0.042,0.308±0.034,Plt;0.01). The cell cycle was significantly shorter in GroupA than in Group B and Group C (Plt;0.05); The durations of G1, S and G2M of the cells in Group A were 16.28, 12.60 and 11.04 h, but those in Group B and Group C were 23.61, 16.90, 21.33 h and 21.56, 19.80, 21.41 h, respectively. The disintegration per minute of the cells was significantly greater in Group A than in Group B and Group C (7281.69±805.50 vs 5916.40±698.11 and 5883.57±922.63，Plt;0.05). Conclusion The lentivirus vector can transfer the bFGF gene into the meniscal fibrochondrocytes, resulting in an increase of the cell proliferation and the collagen synthesis.
Objective To compare the cl inical results of two plating osteosynthesis techniques, open reduction and plating ostosynthesis (ORPO) and minimal invasive plating osteosynthesis (MIPO), in surgical treatment of mid-distal humeralshaft fractures. Methods From March 2004 to October 2006, 40 cases of closed unilateral mid-distal humeral shaft fractures were surgically treated with MIPO or ORPO. In the MIPO treated group (n=19), there were 14 males and 5 females, with a mean age of 39.05 years. Fractures involved in middle humeral shaft in 10 cases and distal fragment in 9 cases. According to OTA classification, there were 3 cases of type A, 13 cases of type B and 3 cases of type C. Four cases compl icated by radial nerve palsies. In the ORPO treated group (n=21), there were 13 males and 8 females with a mean age of 39.05 years, including 14 cases of type A and 7 cases of type B fractures according to OTA classification. The fractures involved in middle humeral shaft in 13 cases and distal fragment in 8 cases. Five cases compl icated by radial nerve palsies. The time from injury to operation in both groups were 2 to 14 days. For patients in the MIPO group, fractures were closely reduced and fixated with an anterior placed plate inserted through two small incisions made at the anterior side of arm, away from fracture sites. The radial nerves were not exposed. For patients in the ORPO group, fractures were exposed, reduced, and fixated with an anterolateral or a posterior positioned plate after careful dissection and protection of radial nerve through an anterolateral or a posterior approach. The operation time, the occurrence of iatrogenic radial nerve palsy and the bone heal ing time were recorded. The functions of the affected shouldersand elbows were evaluated with UCLA end-result score and Mayo elbow perform index (MEPI), respectively. Results All the wounds in both groups healed primarily. There was no iatrogenic radial nerve palsies in the MIPO group after surgery; however, 5 cases of transient iatrogenic radial nerve palsies were identified in the ORPO group after surgery, and the function of radial nerve recovered in these cases at the last follow-up. Eighteen cases were followed up 14-44 months (mean 25.44 months) in MIPO group, and 19 cases were followed up 13-48 months (mean 32.11 months) in ORPO group. The mean bone heal ing time was 17.06 (12-32) weeks in MIPO group and 16.11 (8-58) weeks in ORPO group, showing no significant difference between two groups (P gt; 0.05). There was no nonunion and hardware failure in both groups. The mean forward flexion of the shoulder was 166.94° (150-170°) in MIPO group and 164.74° (130-170°) in ORPO group. The mean UCLA shoulder score was 34.78 (33-35) points in MIPO group and 34.42 (30-35) points in ORPO group. The mean range of motion of the elbow in MIPO and ORPO groups was 133.33° (120-140°) and 136.7° (120-140°), respectively. The MEPI in these two groups was 99.44 (90-100) and 99.74 (95-100) points, respectively. There was no statistically significant difference between two groups in all indexes mentioned above. Conclusion The good results could be obtained when ORPO and MIPO technique are appl ied to treat mid-distal humeral shaft fractures. MIPO technique has advantages to not expose the radial nerve and to decrease the occurrence of iatrogenic radial nerve palsies.
【Abstract】 Objective To establ ish a stable animal model for glucocorticoid-induced avascular necrosis of femoral head in rabbits. Methods Thirty-six adult New Zealand rabbits were randomly divided into four groups:ten were injected twice with l i popolysaccharide (group A), ten were treated with a combination of l i popolysaccharideand methylprednisolone (group B), ten were injected three times with methylprednisolone (group C), and six wereinjected normal sal ine as a control (group D). MR imaging was performed in the rabbits before the first injection ofl i popolysaccharide or methylprednisolone, and at 2, 4, and 6 weeks after the last injection of l i popolysaccharide ormethylprednisolone. Histopathological changes in the femoral heads were observed by l ight microscope and transmission electron microscope at the end of six weeks after the injection. Vascular infusion with Chinese ink was made to evaluate the morphological changes of blood vessels in the femoral head. The percentage of trabecular bone area and empty lacunae and microvascular density were measured. According to the histological and MR imaging appearance of the femoral heads in all groups, the incidence of osteonecrosis of every group was calculated. Results Listlessness, blepharal hyperemia,less activity and reduced diet were found in the rabbits of groups A and B after injected with l ipopolysaccharide. At 3 weeks after the final injection, the body weight of groups B and C was decreased. At 4 weeks after the final injection, the body weight of groups A and D was increased. No abnormal signal could be detected on MR images in rabbits of all groupsbefore injection and at 2 weeks after the injection. At 4 weeks and 6 weeks after the last injection, irregular low signal on T1-weighted images and irregular low or high signal on T2-weighted images could be detected on MR images in rabbits of groups B and C, no abnormal signal could be detected on MR images in rabbits of groups A and D. At 6 weeks after the last injection,the trabecular bone of group B became thin and sparse, some were broken. The percentages of empty lacunae were 11.8% ± 4.7%, 34.4% ± 6.2%, 20.0% ± 4.7% and 9.3% ± 4.6%; the percentages of trabecular bone area were 59.2% ± 6.8%, 40.1% ± 6.0%, 51.5% ± 5.6% and 63.2% ± 8.3%; and the microvascular densities were 14.3% ± 2.7%, 4.5% ± 2.1%, 10.2% ± 3.1% and 15.4% ± 4.1% in groups A, B, C and D respectively. There were statistically significant differences between group B and groups A, C, D (P lt;0.01). The fatty tamponade accumulated in the medullary cavity and intramedullary vascular sinusoids were pressed by the l ipocytes and became narrow. Limposomes were found in osteocytes and vascular endothel ia of group B and group C. Osteocytes of group B crimpled and pyknosis or karyolysis of chromatin were observed in these osteocytes, nuclearmembrane of the osteocytes was discontinous. Vascular endothel ia became swollen and the cell junctions widened or were destroyed in groups A and B. The incidence of osteonecrosis in group B (88.9%) was higher than that in group C (22.2%, P lt; 0.05). There was no osteonecrosis occurred in groups A and D . Conclusion Methylprednisolone combined with l ipopolysaccharide can induce typical rabbit model for early avascular necrosis of femoral head.
Objective To investigate the possibility of constructing eukaryoticexpression vector for human angiopoietin 1（hAng-1），transfecting it to bonemarrow mesenchymal stem cells (MSCs) so as to repair bone defect. Methods The eukaryotic expression vector pcDNA3-hAng-1 was constructed by recombinant DNA technique, transfected into MSCs by liposome DOTAP, and selected with G418. The hAng-1 expression of mRNA and protein was detected by reverse transcript-PCR and Western Blot. Results After the recombinant eukaryotic expressionvector for hAng-1 was digested with Xho-I and BamH-I, electrophoresis revealed 1.4 kb fragment for hAng-1 gene and 5.4 kb fragment for pcDNA3 vector. In the transfected MSCs, the mRNA and protein expression of hAng-1 gene were detected with reverse transcriptPCR and Western Blot. Conclusion The constructed eukaryotic expression vector hAng-1 could be expressed in the transfected MSCs, thus to provide the basis for bone repair with tissue engineering.
OBJECTIVE: To study the proliferation change of tunica intima and smooth muscle in artery after hydrolic dilation for potential clinical use. METHODS: Sixten adult New Zealand rabbits were randomly divided into 4 groups, named group A, B, C and D. Right carotid arteries of rabbits of those 4 groups were dilated by hydrolic dilation with different pressures with 0 kPa, 40 kPa, 80 kPa, and 120 kPa respectively. The arterial calibers, thickness of tunica intima and smooth muscle were analyzed by automatic medical photograph analyzer immediately, 1 week and 2 weeks later respectively. RESULTS: The arterial calibers in the experimental group were larger than those in control group after immediate hydrolic dilation and 1 week later (P lt; 0.01). At 2 weeks, the arterial calibers in group B and D has no significant difference compared to group A (P gt; 0.05), and those in group C were larger than that of group A (P lt; 0.01). There were no significant difference in thickness of tunica intima and smooth muscle between the experimental group and control group (P gt; 0.05) after immediate hydrolic dilation. At 1 and 2 weeks after dilation, there were no significant difference between group A and group B (Pgt; 0.05), and those in group C and D were all larger than those in group A (P lt; 0.01). No obvious proliferation of tunica intima were observed in group B at 2 weeks after hydrolic dialation, but the proliferation of tunica intima could be observed in group C and D, especially in group D. CONCLUSION: Caliber of artery can be expanded by hydrolic dilation with higher pressure, but the proliferation of tunica intima and smooth muscle may be occurred in hydrolic dilation with higher pressure over 80 kPa, therefore it is safe to use hydrolic dilation with pressure no more than 40 kPa.
Objective To investigate the possibility of constructing eukaryotic expression vector for human glial derived neurotrophic factor （hGDNF）, transfecting it to spinal cord tissue of rats so as to treat acute spinal cord injury. Methods The eukaryotic expression vector pcDNA3-hGDNF was constructed by recombinant DNA technique, transfected into glial cell and neuron of spinal cord by liposome DOTAP as experimental group. In control group, mixture of empty vector and liposome was injected. The mRNA and protein expressions of hGNDF were detected by RT-PCR and Western blot. Results After the recombinant eukaryotic expression vector for hGDNF was digested with Hind III and XbaⅠ, electrophoresis revealed 400 bp fragment for hGDNF gene and 5 400 bp fragment for pcDNA3 vector. In the transfected spinal cord tissue, the mRNA and protein expressions of hGDNF gene were detected with RT-PCR and Western blot. Conclusion The constructed eukaryotic expression vector pcDNA3hGDNF could be expressed in the transfected spinal cord tissue of rat, so it provide basis for gene therapy of acute spinal cord injury.