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Objective:This study aimed to construct a lentiviral expression vector for microRNA-194 and investigate its effect on the metastasis of human osteosarcoma cell line U2-OS. Methods:Pri-and mature miR-194 amplified by PCR were inserted into the plenty-GFP vector and identified by restriction endonuclease digestion and nucleotide sequencing. The osteosarcoma cell line U2-OS was transfected with the lentivirus. Then, the stable transfected cells were used in Transwell and wound healing assay. Results:Restric-tion analysis and sequencing showed that the recombinant lentiviral expression vector was constructed correctly. The titers of obtained overexpression and suppression expression recombinant lentivirus were 1.5*108 and 4*108 TU/ml. Cell metastasis ability was signifi-cantly different in different experimental groups (P<0.01). Conclusion:The lentiviral expression vector for microRNA-194 was suc-cessfully constructed. MicroRNA-194 could influence the metastasis of the osteosarcoma cell line U2-OS;thus, it could be further ex-plored as a potential target in osteosarcoma therapy.
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Objective To identify the specific microRNA (miRNA) that can be taken as a molecular marker for human bone marrow-derived mesenchymal stem cells (MSCs). Methods MSCs were isolated and cultured from bone marrow through density centrifugation and then were induced to differentiate into osteoblasts and chondrocytes. Samples of MSCs, osteoblasts and chondrocytes were detected by miRNA microarrays single channel fluorescence chip to determine the expression levels of miRNAs. Significance Analysis of Microarrays ( SAM, version 2.1 ) software was used to analyze the raw data to determine the miRNAs overexpressed in MSCs, which was validated in the same sample using real time reserve transcriptase polymerase chain reaction (RT-PCR). Results MSCs were successfully isolated from bone marrow and induced to differentiate into osteoblasts and chondrocytes in vitro. Microarrays showed that eight miRNAs (has-miR-424, has-miR-34a, has-miR-593, has-miR-10a, has-miR-148a,has-miR-602, mmu-miR-709 and mmu-miR-665) were overexpressed in MSCs but underexpressed in osteoblasts. Three miRNAs including has-miR-424, PREDICTED_MIR189 and mmu-miR-665, were overexpressed in MSCs but underexpressed in chondrocytes. The has-miR-424 expression in MSCs was 6.6times higher than in osteoblasts and 4.4 times higher than in chondrocytes. The results of real time RTPCR showed that the miR-424 was overexpressed in MSCs, 3.6 times higher than that in osteoblasts and 3.1 times higher than that in chondrocytes, which was coincident with the results of microarray. Conclusions The screened MSCs express more miRNAs in comparison with osteoblasts and chondrocytes,play important roles in maintaining self renewal and undifferentiation of MSCs and is a promising specific molecule marker for MSCs.
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[Objective]The purpose of this study was to describe mid report the result of the ulnar nerve transfer to biceps muscle to restore elbow flexion after acute and delayed upper brachial plexus injuries.[Methods]Two patients with acute brachial plexus injury (the time between the injury and the operation were six and eight months) and three patients with delayed brachial plexus injury(the time between the injury and the operation were from twevle to eighteen months) underwent nerve transfer using fascicles of the ulnar nerve to the motor branch of the biceis muscle. The average age of the patients was twenty eight and the mean follow-up periods were nine months after the surgery. Patients were evaluated with regard to reinnervation of the biceps, ulnar nerve function, elbow flexion strength, and grip strength.[Results]For the two acute patients, the first sign of biceps muscle contraction were observed within 1 week, the average time required for reinnervation of the biceps after nerve fascicle transfer was within six months. For the three delayed patients, the first sign of bicep muscle contraction was observed in about three month, and the average time required for reinnervation of the biceps was ten months.Hypoesthesia of the ulnar nerve was clinically abserved in three patients, but this symptom disappeared within month with no treatment.Compared with those delayed cases, the acute patients had faster and better recovery of their olbow flexion function.However, all patients achieved grade-3 or better elbow flexion strength according to the grading system of the Medical Research Council.[Conclusion]The author recommend this safe, simple and effective Oberlin procedure for brachial plexus injuries involving the C5、6 or C5~7 nerve roots.
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Objective To compare and evaluate the defect-repaired capabilities of human bone morphogenetic protein-2(hBMP-2) gene modified tissue engineered bone in the segmental bone defect model of rabbit's radius.Methods Rabbit's bone mesenchymal stem cells (BMSCs)were transferred with hBMP-2 gene through Adeno-XTM adenoviral expression systems,then seeded onto the compound scaffold of calcium phosphate cemept(CPC)and fibrin glue(FG)to construct a new kind of gene modified tissue engineered bone after proliferation in vitro for three weeks(Group A).Meanwhile,the compound scaffold of calcium phosphate cement(CPC)and fibrin glue(FG),which were seeded by rabbit's bone knesenchyrmal stem cells(BMSCs) after proliferation in vitro for three weeks(group B)and the compound scaffold without cells(Group C)acted as control groups.Then,three kinds of reconstructive modalities were implanted into segmental bone defect of donator rabbit's radius.Besides these three groups,bone defect model of rabbit's radius without treatment(Group D)represented blank group.The defect-repaired capabilities were assessed by gross observation,radiograph,Single Photo Emission Computed Topography (SPECT)and histological analysis in the 4th week,8th week and 12th week after operation.The rates of bone healing in the different groups were compared each other.Results All defects that had been treated with implants(Group A,B,C)exhibited new bone formation and could attain osseous tissue healing 12 weeks after operation,but defects in blank group(Group D)were repaired only by fibrous tissue.The defects in the Group A regenerated more new bone,bridged earlier and stronger than those in the Group B and Group C.The quantity and rate of new bone formation in the Group B and Group C had no significant difference and the rates of bone healing in different groups showed the same results.Conclusion hBMP-2 gene modified tissue engineerod bone have better potential to form new bone and the rate of bone healing in repairing bone defects is higher,so this way is an optimal kind of material for artificial bone graft.
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[Objective] To analyze the treatment of malignant of highly aggressive bone tumors of pelvis by microwave-induced hyperthermia.[Methods]A novel surgical model was devised:after careful dissection of the tumor-bearing bone from surrounding normal tissues,the microwave antennae array was inserted into the tumor mass for emitting electromagnetic microwave which produced tumor cellular death via thermo-coagulation.No special reconstruction procedure was necessary,excepting the strengthening measures.[Results]From May 1994 to December 2005,152 patients with pelvic malignant or highly aggressive tumors received radical thermotherapy.Among 67 patients with stage IB tumors,48 patients achieved local and systematic control.Among 61 patients with stage IIB tumors,19 patients died from lesion,and the remaining 42 patents did not developed either metastasis or local recurrence after 3 to 11 years.Of 24 patients with pelvic metastatic lesions,11 patients collapsed during six months to three years,and 13 patients still lived without evidence of disease within one to seven years.In the majority of the patients,functional and cosmetic acceptable limbs were reserved.[Conclusion]The results revealed that the novel and greatly simplified method is justified from both oncological and functional standpoints.Hyperthermia should deserve more attention than it has in this field.
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[Objective]To analyze the clinical effect of microwave hyperthermia in limb salvage surgery for malignant bone tumor of extremities. [Methods]From July 1999 to July of 2005, 309 patients with malignant or bone tumors of extremities were treated by heat necrosis of tumor-bearing bone in situ for limb salvage.The most common diagnosis was osteosarcoma. The first step of the traditional limb salvage was en bloc resection of the tumor-bearing bone. For the novel method, the tumor bearing bone was just separated from surrounding normal tissues, and was devitalized by hyperthermia in situ.After re-strengthening the dead bone, its mechanical property became strong enough to support the body weight.[Results]The beyond 3 years survival rate was 60.2% for high-grade malignancy. In great majority of the patients, cosmetic and useful limbs were preserved. The complication rate was lower than that in the literature reports.[Conclusion]The long term experience has proved that the new method has made its way in the field of orthopedic oncology. The applying of hyperthermia for treatment of bone tumors is an effective, simple, and inexpensive method. The oncological and functional results are encouraging. Hyperthermia should deserve more attention than it has in the clinical practice.
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[Objective]To explore the effective treatment method of the articular fracture in distal radius.[Method]Severely comminuted AO type-C3 intra-articular fractures of the distal end of the radius were treated with combined internal and external fixation.The Gartland and Werley system and the Green and O'Brien system were used for comparison of the pre-operative and after operative evaluation.Total articular congruity had been assessed with both clinical rating systems.[Result]At a mean of ninteen months following-up,the mean arc of flexion-extension was 78% of that on the uninjured side and the mean grip strength was 82% of that on the uninjured side.The mean total articular incongruity(the gap plus the step-off)averaged 2 mm,and the radial length was restored to a mean of 11 mm.According to the Gartland and Werley demerit-point system,seventeen of the patients had a good or excellent result.According to the modified Green and O'Brien clinical rating system,eleven had a good or excellent result.Postoperative total articular incongruity had a moderately strong correlation with the outcome as assessed with both clinical rating systems.[Conclusion]Open reduction and combined internal and external fixation of AO type-C3 fractures can restore radiographic parameters to nearly normal values,maintain reduction throughout the period of fracture-healing,and provide satisfactory functional results.
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[Objective]To investigate the effect of transforming growth factor ?1(TGF-?1) genes transfection on the proliferation and differentiation of chondrocyte by adenovirus vector,and to observe the quality in repair cartilage defect through constructing tissue-engineered cartilage.[Method]Using replicat ion defective adenovirus Adeno-X~(TM) as a carrier,Articular chondrocytes were transferred by high titers level recombinant adenovirus taking TGF-?1 genes.Ultromicrostructure,prolife ration anddifferentiation were observed by light and electron microscope,flow cytometry and so on.Induce expression of exogenous genes coding protein and cartilage cell phenotype were detected by Immunocytochemistry and Northern blot.Gross observation,histology and effect classification were used to evaluate results in repair cartilage defect by combi nation of infected chondrocytes and bone matrix gelatin(BMG).[Result]Immunocytochemistric staining showedthe expression of exogenous gene coding proteins after infection,and procollagen Ⅱ mRNA in cells was detected increasingly by Northern blot.TGF-?1 stimulated proliferation of chondrocytes in primary cultured,and resulted in recruitment of articular chondrocytes into S-G2/M phase.Chondrocytes seeded onto BMG showed high level of proliferation.Transplantation in vivo showed: cartilage defect was repaired satisfactorily by Combination of BMG and infected chondrocytes,and the structure of repair tissue got close to normal articular cartilage.[Conclusion] Articular chondrocytes prolifera tion could be stimulated by adenovirus vector taking TGF-?1 genes,which could be used to constructed tissue-engineered cartilage,and applied in repairing joint cartilage defect.
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[Objective]To investigate whether fibroblasts from malignant bone tumor could support osteoclast differentiation and bone resorption.[Method]Fibroblasts isolated from 8 fresh tumor samples were cultured in vitro.At passage two,part of these fibroblasts were co-cultured with peripheral blood monocytes.M-CSF,OPG and neutralizing anti-TNF-? antibody was added to the culture respectively.A Transwells system was also applied to observe the secretion of solvable factors in fibroblasts.At day 1,day 14 and day 21,the cultures on coverslips and bone slices were stopped and examined for the formation of tartrate resistant acid phosphatase(TRAP)positive multmucleated cells(MNCs)and lacuna resorption pits respectively.The number of lacuna resorption pits on bone slices,which was a marker of OC activity,was compared between the groups.Another part of the fibroblasts were cultured alone,and RT-PCR was performed to investigate the expression of RANKL and TNF-? mRNA in the fibroblasts.[Result]TRAP positive MNCs and lacuna pits were observed in the co-culture group in the presence of M-CSF,but not in the absence of M-CSE.It was also the case in the Transwell group,even though the number of lacuna pits was resuced.OPG completely inhibited the formation of TRAP positive MNCs and lacuna pits,while anti-TNF-? had not inhibiting effect on this process.RT-PCR results showed that both RANKL and TNF-? mRNA were positive in all the fibroblast involved.[Conclusion]In the presence of M-CSF,fibroblasts from malignant bone tumor are capable of supporting osteoclast formation and activity through expression of RANKL.
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BACKGROUND: At present, there are only morphological observation about the femoral osteolysis in domestic literatures and reports of quantita tive study are also few.OBJECTIVE: To quantitatively analyze the changing status of osteolysis in proximal femur after total joint replacements (TJR) through the changing rules of bone density in proximal end of femur.DESIGN: Observation on patients before and after self-comparison.SETTING: Department of Orthopedics, Tangdu Hospital of Fourth Military Medical University of Chinese PLA.PARTICIPANTS: Twenty-eight hips in 26 patients received total hip replacements in the Department of Orthopedics, Tangdu Hospital of Fourth Military University from March 1994 to March 2004, including 16 hips in 14 male patients and 12 hips in 12 female patients, were selected. Types of prostheses: 17 hips in 16 patients with ameliorated Moore cemented prostheses were taken as cemented prosthesis group with a mean age of 57 years; 11 hips in 10 patients with microbores on the surface of implant were taken as cementless prosthesis group with a mean age of 55 years.Patients were diagnosed as traumatic arthritis before operation with the mean Harris score of 49 (20-77) points on hip. Age, gender and diagnosis after operation in patients of two groups were matched.METHODS: The gray degrees of X-ray in patients of two groups were measured with computer image analyzing, relative values were obtained,I.e. The average gray degrees of 1.0-2.0 cm2 area in femoral trochanter and iliac bone were measured with the same X-ray; Differences between them represented the relative value of bone density in greater trochanter of femur. Changing rules of bone density were quantitatively analyzed.MAIN OUTCOME MEASURES: Relative values of bone density in greater trochanter of femur of patients in two groups one week before and after operation, during the follow-up time were measured respectively.RESULTS: A total of 26 patients (28 hips) with the follow-up time of 9-126months were all involved in the analysis of results. Relative values of bone density were increased to different degree one week after operation. And rate of osteolysis was 100% with a mean value of 57.4 (9-118) in greater trochanter of femur from 17 hips of 16 patients in the cemented group during the follow-up time; Relative value of bone density in greater trochanter of femur in 10 hips of 11 patients in the cementless group during the follow-up time were increased to different degree one week after operation.Rate of osteolysis changing was 100% with a mean value of 72.8 (14-130).Differences between two groups were not significant (P ＞ 0.05). Changes of osteolysis firstly appeared in the 9th month of post-operation and were obvious 2-4 years after operation and lessened in the 6th year.CONCLUSION: There are osteolysis in cemented and cementless prostheses after total hip replacement and no significant differences between two kinds of prostheses.
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BACKGROUND: Mesenchymal stem cells (MSCs) are capable of differentiating into a variety of lineages, including bone, cartilage, or fat, depending on the inducing stimuli, specific growth and differentiation factors.Recombinant human bone morphogenetic protein 2 (rhBMP-2) produced by gene engineering has an obvious osteoinductive activity and can induce undifferentiated mesenchymal cells into cartilage and bone irreversibly, resulting in new bone formation. Basic fibroblast growth factor (bFGF) modulates chondrogenic and osteogenic differentiation of MSCs.OBJECTIVE: To investigate the effect of bFGF and rhBMP-2 on the differentiation and proliferation of cultured rabbit mesenchymal stem cell in order to find out an optimal way of osteogenesis instead of conventional osteogenic supplements (OS).DESIGN: A randomized and controlled trial.SETTING: General Institute of Orthopaedic Oncology, Tangdu Hospital,Fourth Military Medical University of Chinese PLA.MATERIALS: The subjects were rabbit mesenchymal stem cells cultured by the author.METHODS: This experiment was conducted at the Center of Orthopaedic Surgery, General Institute of Orthopaedic Oncology, Tangdu Hospital,Fourth Military Medical University of Chinese PLA from June 2004 to December 2004. ①Rabbit MSCs cultured in vitro were treated with different growth factor (100 μg/L rhBMP-2, 100 μg/L bFGF, 10 μg/L rhBMP-2and 100 μg/L bFGF and OS; ②The proliferation and differentiation of MSCs were observed through activity of MTT, expression of alkaline phosphatase(ALP), and von Kossa staining.MAIN OUTCOME MEASURES: the rate of proliferation and the activity of ALP.RESULTS: ①rhBMP-2 could promote the proliferation and differentiation of MSCs, especially the cell differentiation; ②bFGF could stimulate the proliferation , the cellular proliferation rate increased 100% as compared with control group, and has no effect on differentiation of MSCs , but it could enhance effect on the cell proliferation of rhBMP-2.CONCLUSION: bFGF and rhBMP-2 are effective induction factors for MSCs. Both of them can stimulate the proliferation and differentiation of MSCs in vitro. bFGF and rhBMP-2 exerted a synergetic action in speeding up the pace of osteoinduction and osteogenesis and can be used to differentiate seed cells for tissue engineering bone.
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BACKGROUND: Patients who suffered total hip replacement are mostconcerned about the survivorship of prosthesis. OBJECTIVE: To evaluate the postoperative curative effect following ce mented and cementless THR with a retrospective method, so as to provideexperience for prolonging the survivoship of prosthesis. DESIGN: Randomized and controlled observation. SETTING: General Center of Orthopaedic Department, General Instituteof Bone Oncology, Tangdu Hospital, Fourth Military Medical University ofChinese PLA. PARTICIPANTS: We admitted 356 patients who underwent THR fromDepartment of Orthopaedics, Tangdu Hospital, Fourth Military Medical U niversity of Chinese PLA between March 1993 and March 2004. Amongthem, 298 were contacted and 105 (108 hips) followed up. The patientsparticipated in the review voluntarily. They were of either gender and haddifferent types of prosthesis. Prosthesis made in China was adopted before2000 and prosthesis made in American STRIKER company after 2000: Prosthesis made in China was made of home-made bone cement; Prosthesisbone cement (import) was provided by American STRIKER prosthesiscompany. Home-made bone cement and import have the same components. Barium was added in both bone cement . The whole operation was con ducted by the physicians who worked in the artificial joint department afterexamination. METHODS: According to informal discussion summary about total hipreplacement of Chinese Journal of Surgery in 1982 and Evaluation Scale ofMayo Total Hip Replacement Curative Effect, we designed follow-up tableby ourselves. Totally 105 (108 hips) patients were followed up, amongthem, 62 (63 hips) were in the cemented group, 43 (45 hips) in the ce mentless group. Pain, function and motion range of the patients and X-raywere evaluated and analyzed respectively. MAIN OUTCOME MEASURES: ① Postoperative pain degrees. ② Postoperative function of hips. ③ Postoperative motion range. ④ width oflight around the prothesis , distance of horizontal or vertical shift of theprosthesis. ⑤ range of ectopic ossification of the prosthesis. ⑥Osteolysisdegree of proximal femur. RESULTS: ①There was no significant difference of lateral femoral painduring follow-up period [Cemented group: 24 hips (38.5%) ,cementlessgroup: 18 hips(40.0% )]. ② Limping appeared in the both two groups ③ There was no significant difference of range of motion above 160° betweentwo groups (Cemented group: 62 hips; cementless group: 44 hips). ④Therewas no significant difference in subsidence of femoral prosthesis and hori zontal or vertical shift of acetabular prosthesis between two groups . ⑤ There was no significant difference of re lative value of femoral proximalbone density between cemented group [57.4(9-118)] and cementless group[72.8( 14-130)]. ⑥There was no significant difference of postoperative cu rative effect, possible survival rate of prosthesis and femoral proximal ex tensive osteolysis of the patients between the two groups. CONCLUSION: Postoperative curative effect of the patients between ce mented group and cementless group are similar, both not obtaining an idealfixed effect. The choice of prosthesis type does not affect the survivorship of prosthesis, but it depends on the age of patients to decide whether rebuilding is necessary or not: Osteolysis is not related to age, gender or prosthesis type of the patients.
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BACKGROUND: Composite with different ratios has various elastic noduli, and this can cause stress protection in implanted body so as to influence on biological integration between composite and host bone and plerosis of bone defection.OBJECTIVE: To measure elastic modulus of tissue engineering bone made of composite between true bone ceramic (TBC) granule and bone cement (BC) and provide experimental data for repairing bone defection at various sites.DESIGN: Controlled study.SETTING: Military Institute of Bone Tumor, Tangdu Hospital of the Fourth Military Medical University of Chinese PLA.MATERIALS: The experiment was carried out in the Military Institute of Bone Tumor, Tangdu Hospital of the Fourth Military Medical niversity of Chinese PLA from August 2002 to March 2003. Ten Kunming mice,weighing 10-15 g, of both genders, were selected in this study. Fresh longtubular cortical bone of 1-year calf, 6 samples of spongy bone at inferior extremity and 6 samples at iddle femur of fresh corpse were also selected in this study.METHODS: Bovine bone morphogenetic protein (bBMP) was xtracted to measure osteogenic-induced activity and make TBC granule. bBMP was mixed with TBC as the ratio of 1:25, and then with BC as the ratios of 0:10, 4:6, 5:5,6:4 and 7.5:2.5. In addition, elastic modulus of tissue engineering bone made of TBC-BC composite was measured and compared with elastic modulus of femur and spongy bone of normal adult males.MAIN OUTCOME MEASURES: Measurement and comparison of elastic modulus.RESULTS: Elastic modulus of composite containing 60% TBC (Ratio between TBC and BC was 6:4) was no significantly different from that of spongy bone at inferior extremity of femur of normal adult males (P ＞ 0.05),but other comparisons of every two subjects were significant difference [femur of the adults: (6.216 7±0.222 9) Mpa; spongy bone: (1.351 7±0.306 9) Mpa;TBC/BC (0:10): (5.710 0±0.166 3) Mpa; TBC/BC (4:6): (3.510 1±0.205 0) Mpa;TBC/BC (5:5): (2.004 1±0.150 0) Mpa; TBC/BC (6:4): (1.501 8±0.005 7) Mpa;TBC/BC (7.5:2.5): (0.900 4±0.025 1) Mpa, P ＜ 0.01].CONCLUSION: Elastic modulus of composite containing 60% tissue engineering bone made of TBC-BC composite is similar to that of spongy bone at inferior extremity of femur of adult males. The composite can be used to repair bone defection near by articular facet so as to prevent from articular degeneration.
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Objective To introduce a new design of interlocking system which is easy in use, makes the distal fracture fragments well aligned and rigidly fixated, reduces exposure to radiation for the surgeon and patient, and allows for a decrease in operating time. Methods The new interlocking system was designed to be a self-locking nail with bevels (b-SLN). According to the bevel principle, the axial force of the nail should be turned into a transverse force so as to control the transverse nail's movement. 10 dry-bone simples were made into the fracture model of the middle-femur to test the prototype nail. The retention of the nail in the intramedullary cavity was evaluated by the radiogram. The mechanical properties of a simulated model of single leg loading were tested on the instron-1342 type MTS. Results The prototype nail performed well as designed. The process was stable and reliable. The retention in the intramedullary cavity was fine. The shearing force between the transverse nail and main nail was enough to cut anything around them. The mechanical properties of b-SLN were similar to those of the Grosse-Kempf nail, better than auto fork compress locked intramedullary nail, and much better than MHUA nail and Ender's nail. Conclusions The structure of b-SLN is simple and reliable. There is no focus-point under stress. Its biomechanic properties are satisfactory. It is easy to use with no need of fluoroscopes in the operating theatre.
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Objective To investigate the specific antitumor effects induced by allogeneic dendritic cells (DCs)/osteosarcoma cell fusion vaccine in rats. Methods Fusion vaccine of DCs derived from Wistar rat bone marrow and osteosarcoma cells (UMR106) derived from SD rat was generated by electroporation method, and purified by immunomagnetic beads coated with monoclonal antibody OX62, then cocultured with T lymphocytes derived from SD bone marrow to stimulate the proliferation of the T lymphocytes. The proportion of CD8+ and 44+ cells was determined by flow cytometry, and the anti-tumor activity of cytotoxic T lymphocytes (CTLs) was determined by MTT assay. The SD rat osteosarcoma model was established and active immunotherapy was performed through intradermal injection, and the survival rate of the model rats was observed. Results After cocultured with allogeneic fusion vaccine, the proliferation of T cells increased significantly, and the proportion of CD8+ cells increased from 34.2% to 74.9%, while of CD4+ cells decreased from 59.2% to 19.1% (P
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AIM: To investigate changes of Ca 2+ activated potassium channels (K Ca) in autogenous vein grafts. METHODS: The contraction of venous ring was measured by means of perfusion in vitro. The intimal proliferation and proliferation of cultured smooth muscle cells (vascular smooth muscle cells, VSMCs) were observed by the means of computerised image analysis and MTT method, respectively. Furthermore, whole cell mode of patch clamp was used to record K Ca of VSMCs isolated from autogenous vein grafts. RESULTS: 1 week after transplantation there were no significant differences of contraction and intimal relative thickness between autogenous vein grafts and control. Contraction and intimal relative thickness of autogenous vein graft were significantly increased 2 weeks after transplantation (P
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Objective To analyze the ultra microstructure and histological properties of implanted composites of decalcified bone matrix (DBM) impregnated calcium phosphate cement (CPC) with recombinant human bone morphogenetic protein-2 (rhBMP-2) in bone defect, and evaluate the osteoplastic efficiency of this composites. Methods The rabbit DBM was prepared beforehand. The composites of DBM impregnated CPC with rhBMP-2 was made at 0.2 proportion of DBM. The rabbit's bone defect of femur condyle was filled with implantation of the composites (group A, n=12) or CPC (group B, n=12) or bone cement (group C, n=12). Animals were sacrificed at 6, 12, or 24 weeks after operation, and the implants were examined by histological technique and scanning electron microscopy (SEM). Results In group A, at the 6th week after operation, the interface region between implants and bone tissue became fuzziness, and was crossed by the generated fibers of bone tissue, and filled with woven bone growing inside into the composites; at the 12th week after operation, blood vessels, osteoblasts and new bone were generated inside of composites; at the 24th week after operation, the bone defects were recovered and became solid union, most of the implants were replaced by new bones. In group B, at the 6th week after operation, the interface of CPC and bone tissue was sharp, and was not crossed by new bones; at the 24th week after operation, the bone defects were still filled with materials of CPC and no new bone was found inside CPC. In group C, at the 24th week after operation, the interface of bone cement and bone remained non-union. Higher osteoblastic activity,more neogenetic blood vessels and higher growth rate of woven bone were observed in group A compared with those in group B. Conclusions For bone defect, the implantation of composites with DBM proportion of 0.2 can stimulate the growth of osteoblast, blood vessel and woven bone. It is biodegradable and can be replaced by autogenous bone.