[Objective]To develop macroporous calcium phosphate cements(CPCs) by incorporating the gelatin microspheres(GMs) and to evaluate the performance of the composite as a bone substitute in vitro and in vivo. [Methods]GMs were prepared by improved emulsified cold-condensation method and macroporous CPCs were developed using GMs with three different weight ratios (0%,2.5% and 5%). The porosity and the compression strength of the three composites were measured to determine the proper weight ratio of GMs. The morphologic changes of osteoblasts were examined with scanning electron microscope at two days after the cells were seeded on the CPCs and GMs/CPCs. The cells were also cultured with different leaching liquor of three kinds of materials (0%,2.5% GMs/CPCs and polystyrene).Cell viability analysis was performed by MTT assay,and alkaline phosphatase was measured with alkaline phosphatase kit. At six months after implanted in the goat vertebre ,the samples with CPCs or GMs/CPCs were obtained and evaluated by X-ray image and histological anatomy.[Results]Porosity of the GMs/CPCs increased with the increase of GMs,but compression strength decreased. The proliferation and differentiation of the osteoblasts were enhanced with the 2.5% GMs/CPCs compared to the CPCs. In vivo study showed that the degradation of GMs/CPCs was improved.[Conclusion]Macroporous calcium phosphate cements can be developed by incorporating gelatin microspheres,and biocompatibility and degradability of the composite can be enhanced. The composite can be used as a bone substitute under non-loaded circumstances.

[Objective] To study the mechanism and clinic characteristic to the serious spinal cord compression from vertebral tuberculosis in the absence of nenrologic deficits.[Method]A total of 15 patients with serious spinal cord compression from vertebral tuberculosis in the absence of neurologic deficits were treated by one-stage debridement,lilac grafting and internal fixation.The clinical characters were retrospectively analyzed.[Result]All these patients had no sinus formation and no recurrence of spinal tuberculosis during average the follow-up of 3.8 years(range:6 months to 7 years).In 5 cases with incomplete paraplegia,3 cases improved 2 grades,1 case was no change and 1 case became serious.[Conclusion]The serious spinal cord compression from vertebral tuberculosis in the absence of neurologic deficits has a long history in illness,the spinal cord is in crisis condition even it can get adjustment by itself.The early one-stage treatment of debridement,iliac grafting and internal fixation can guarantee the restore the spinal cord and spine stability.

[Objective]To study various surgical approaches to the treatment of scapular neck and body fratures,and evaluate the clinical results.[Method]From January 1996 to December 2006,thirty-two cases with scapular neck and body fratures including 21 males and 11 females with age range from 18-56 years (mean 29 years) that had been admitted to the author's hospital were retrospectively analyzed.On the basis of the fracture patterns,straight incision along lateral border of the scapula,posterior approach,Judet approach were performed with plates or lag screws for open reduction and internal fixation.[Result]All cases were followed up for a period of 8-22 months.The mean time of bone union was 6-8 weeks.According to Hardegger's evaluation,22 cases showed excellent results,7 good,2 fair,1 poor.[Conclusion]Open reduction and internal fixation are emphasized to the severe separated scapular neck and body fractures.Straight incision along lateral border of the scapula,posterior approach or Judet approach can be chosen on the basis of the fracture patterns.Most scapular neck and body fractures can be treated by straight incision approach along lateral border of the scapula.This surgical approach can provide exposure of the fratures directly with saved surgical time and attain perfect reduction and fixtion with less trauma.

[Objective]To repair segmental bone defect with the composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin.[Method] Bone defects were created in 36 New Zealand rabbits on the bilateral radii and treated with three kinds of implantations:A,composite of deproteinised cancellous bone,BMP and fibrin;B,of deproteinised cancellous bone;C,blank control.The defects were observed by entgenography,optical microscopy,and electron-microscopy at 2,4,8,12,16 weeks.[Result] The defects treated with A implantation regenerated much more new bone and bridged earlier than the defects treated with B implantation and got completely repaired 16 weeks after operation.The defects with B and C implantation couldn't get osseous tissue healing.[Conclusion]The composite of deproteinised cancellous bone,bone morphogenetic protein(BMP) and fibrin can be effectively used to repair segmental bone defect.

[Objective]To investigate the effect of an effervescent-sucrose on the properties of calcium phosphate cement. [Method]The sucrose particles were mixed with CPC powder at sucrose/(sucrose+CPC powder) mass percentage of 0%,10%,20%,30%,40%.The samples were characterized by compressive strength,X-ray diffraction,SEM techniques and degradation in vivo.[Result]The samples decreased on the mechanical properties and increased on the rate of macropore and total porosity,they were effected significantly among groups by added effervescent(P

[Objective]To explore the outcome of repairing nerve defects with nerve allografts stored in green tea polyphenol solution.[Method]Forth-eight male mice were randomly divided into 4 groups of nerve grafting,with 12 rats in each group.A 1.0 cm sciatic nerve segment,5 mm away from infrapiriform foramen,was removed and repaired by 4 kinds of nerve allografts.Group A:autografts.Group B:allografts.Group C:cryopreserved nerve allografts.Group D:nerve allografts stored in green tea polyphenol solution.At 6 weeks and 12 weeks,a series of examinations were performed,including the gross appearance,electrophysiological test,histological observation,electron microscopic study and quantitative analysis with image analysis system.[Result]All the parameters of groups A and D were better than those in groups B and C(P

[Objective]To study the combination of calcium phosphate cement(CPC) and morselized bone and their optimum mixing ratio. [Methods]Bilateral nemora of macro-ears rabbits were made into morselized bone.There were two groups:experimental group and control group.In the experimental group,the ratios of morselized bone to CPC were 1 to 1,1 to 2,1 to 3,1 to 4 and 1 to 5.In the control group CPC was used after it was solidified.The maximum compression strength and solidified time of the materials in experimental and control groups were tested.The cell multiplication was evaluated by MTT after mesenchymal stem cells were cultivated.[Results]The cell multiplication in materials mixed with ratios of 1 to 2 and 1 to 3 was better than those in the materials mixed with the other ratios by MTT.It indicated that there was a significant difference(P

[Objective]To observe the effect of vacuum sealing drainage(VSD) on bacteria and microcirculation of acute explosion wounds in pigs.[Method]Twelve blast wounds,created by explosion of a specific type of electric detonations which were fixed at 1 cm over the skin of the hips of six Lanzhou healthy pigs(30-40 kg),were divided into two matched groups.Debridement was performed at 6 hours after injury.Group A was treated with conventional dressing change,and group B was treated with VSD under the pressure of-20kPa.Tissue specimens collected from different sites of the wound bed before and at 12,24,48,72 hours after treatment,and experienced bacteria counting.The microcirculation of the blast wounds was examined by color B-mode ultrasonic diagnostic equipment before and 72hours after treatment.[Result]The difference of wound bacteria loads between group A and group B was statistically signficant at different time points.Bacteria loads in group B were increased to 105cfu/g at 48 h after treatment,compared with group A at 24 h.No signal of blood flow in blast wound was found before treatment.In contract,the blast wound had plenty of signals of blood flow in group B.[Conclusion]VSD could reduce the bacteria loads,and delay the time of infection.Meanwhile it improved the microcirculation of the acute blast wound.

[Objective]To confirm the effect of combination of calcium phosphate cement and small amounts of autoallergic micromorselized bone for reparing bone defect and provide the basis for clinical use.[Method]The animal models of bilateral radius defect were created by surgery on Japan white big ear rabbits.The combination with a ratio of 3 to 1 in one lateral leg was implanted in experimental group,and calcium phosphate cement was used in the control group.The X-rays,bone density,and maximum torsional moment were carried out at different time points,and osteogenesis and degradation of the materials in the two groups were analyzed.[Result]Enhancement of osteogenesis was found in the experimental group,and the materials were enclosed significantly by bony callus at the 8~(th) week,the defects were repaired and the materials were degraded completely at the 16~(th) week.The bone mineral content in the experimental group was higher than that in the control group(P

[Objective]To analyze the biodegradation properties and active osteogenesis features of implanted composites of gelatin microspheres(GMs) impregnated with calcium phosphate cement(CPC) and recombinant human bone morphogenetic protein-2(rhBMP-2) in bone defect.[Method]rhBMP-2 loaded gelatin microspheres was incorporated in rhBMP-2/CPC during setting.Thirty rabbits were divided into groups A,B and C(10 each).The rhBMP-2/GMs /CPC,GMs/cpc and rhBMP-2/cpc was implanted into the rabbits of group A,B and C,respectively.The biodegradation properties and active osteogenesis features of implanted composites bone substitute was evaluated by radiography,histology,bone mineral density(BMD)after the composites were implanted into the bone defects at rabbit radius for 6,12 weeks respectively.[Result]Significant implant resorption and bone ingrowth were observed in all rhBMP-2/GM/CPC treated defects while the defects treated with rhBMP-2/CPC implants showed slight resorption of CPC and the defects treated with GM/CPC implants showed slight formation of new bone.[Conclusion]The result of this study suggested that the rhBMP-2/GMs/CPC composite could be used as material for bone graft substitute.