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Natural degeneration or trauma of articular cartilage all can lead to its structural and functional damage. Without blood supply and nerve innervation, chondrocytes in the matrix lacunae obtain essential nutrients and excrete metabolites mainly through osmosis, finally leads to its low metabolic activity and difficulty in self-repair after injury. At present, drug conservative treatment and surgical operation are the main clinical treatment, but both of them can't meet the clinical needs well. The development of cartilage tissue engineering provides a new direction for the repair of articular cartilage injury, in which growth factors plays a very important role. Growth factors, together with seed cells and cell scaffolds, constitute the three elements for the construction of tissue-engineered cartilage. Among them, Growth factors can significantly promote cell proliferation and differentiation and induce their functions. Various growth factors synergistically mediate the differentiation of seed cells into chondrocytes. In recent years, stem cell cartilage tissue engineering developed rapidly, which has opened a new way for repair of articular cartilage damage due to its abundant cell resources, small damage to body itself, strong ability of proliferation and directional differentiation, biological repair and other prominent advantages. Different types of hydrogels and stem cells show different abilities to support chondrogenesis and require different growth factors to induce chondrocyte differentiation. Traditional growth factors for tissue engineering include transcription growth factor β, insulin-like growth factors, bone morphogenetic proteins, fibroblast growth factors and cartilage derived morphogenetic protein. Recently, some scholars found that platelet-rich plasma, platelet-rich fibrin, Kartogenin and Mechano-growth factor can also effectively induce chondrogenic differentiation of stem cells and maintain chondrocyte phenotype. In addition, some synthetic compounds such as dexamethasone and inorganic particles can also promote the differentiation of stem cells into cartilage. This article systematically summarized the new progress of the traditional growth factors, emphatically introduced the new discovered growth factors and some synthetic compounds and inorganic particles, which can induce stem cells into cartilage. Finally classified the different sources of stem cells and its suitable growth factors, and gave an outlook of the next research direction of growth factors.
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BACKGROUND: Hyaluronan-methylcellulose hydrogel cannot only be conjugated with short peptide sequences and growth factors to achieve sustained release, but also has a role in blocking dural defects and reducing inflammation. It is an ideal biomaterial for the treatment of spinal cord injury. OBJECTIVE: To investigate the effect of neurotrophin-3 modified hyaluronan-methylcellulose (HAMC-NT-3) hydrogel on the recovery of neurological function in rats with spinal cord injury. METHODS: Fifty-four female Sprague-Dawley rats (provided by the Experimental Animal Center of the Academy of Military Medical Sciences in China) were randomly divided into three groups (n=18 per group) . The sham group only underwent T10 laminectomy. In the model group and the experimental group, an aneurysm clip was used to establish spinal cord injury models after T10 laminectomy. The experimental group was locally injected with HAMC-NT-3 hydrogel. The Basso Beattie Bresnahan function scoring was performed at 1 day, 1, 2, 3, 4, 5, 6, 7, and 8 weeks after surgery. The inclined plane test was performed at 4, 6 and 8 weeks after surgery to evaluate the recovery of hindlimb motor function. ELISA was used to detect the concentrations of inflammatory factors in the spinal cord at 1 week after surgery. Immunohistochemical staining was used to observe the area of syringomyelia, glial fibrillary acidic protein expression and nerve regeneration at 8 weeks after surgery. RESULTS AND CONCLUSION: (1) The Basso Beattie Bresnahan scores of the model group and the experimental group were lower than those of the sham group at various time points after surgery (P < 0.05) . The Basso Beattie Bresnahan scores of the experimental group were higher than those of the model group at 4-8 weeks after surgery (P < 0.05) . (2) In the inclined plane test, the maximum inclined angles of the model group and the experimental group at each time point after surgery were lower than that of the sham group (P < 0.05) . The maximum inclined angles of the experimental group at 6 and 8 weeks after surgery were higher than those of the sham group (P < 0.05) . (3) The concentrations of tumor necrosis factor-α, interleukin-1β, interleukin-6 and interleukin-10 in the experimental group and the model group were higher than those in the sham group (P < 0.05) . The concentrations of tumor necrosis factor-α, interleukin-1β and interleukin-6 in the experimental group were lower than those in the model group (P < 0.05) . The concentration of interleukin-10 in the experimental group was higher than that in the model group (P < 0.05) . (4) Immunohistochemical staining showed that the expression levels of glial fibrillary acidic protein in the experimental group and the model group were higher than those in the sham group, while the expression of glial fibrillary acidic protein in the experimental group was lower than that in the model group. The area of syringomyelia in the experimental group was smaller than that in the model group (P < 0.05) . These results indicate that local injection of HAMC-NT-3 hydrogel can effectively inhibit inflammation as well as astrocyte activation and proliferation, reduce fibrous scar formation, and promote the protection of nerve tissue and the recovery of hindlimb motor function after spinal cord injury.
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Natural degeneration or trauma of articular cartilage all can lead to its structural and functional damage.Without blood supply and nerve innervation,chondrocytes in the matrix lacunae obtain essential nutrients and excrete metabolites mainly through osmosis,finally leads to its low metabolic activity and difficulty in self-repair after injury.At present,drug conservative treatment and surgical operation are the main clinical treatment,but both of them can't meet the clinical needs well.The development of cartilage tissue engineering provides a new direction for the repair of articular cartilage injury,in which growth factors plays a very important role.Growth factors,together with seed cells and cell scaffolds,constitute the three elements for the construction of tissue-engineered cartilage.Among them,Growth factors can significantly promote cell proliferation and differentiation and induce their functions.Various growth factors synergistically mediate the differentiation of seed cells into chondrocytes.In recent years,stem cell cartilage tissue engineering developed rapidly,which has opened a new way for repair of articular cartilage damage due to its abundant cell resources,small damage to body itself,strong ability of proliferation and directional differentiation,biological repair and other prominent advantages.Different types of hydrogels and stem cells show different abilities to support chondrogenesis and require different growth factors to induce chondrocyte differentiation.Traditional growth factors for tissue engineering include transcription growth factor β,insulin-like growth factors,bone morphogenetic proteins,fibroblast growth factors and cartilage derived morphogenetic protein.Recently,some scholars found that platelet-rich plasma,platelet-rich fibrin,Kartogenin and Mechano-growth factor can also effectively induce chondrogenic differentiation of stem cells and maintain chondrocyte phenotype.In addition,some synthetic compounds such as dexamethasone and inorganic particles can also promote the differentiation of stem cells into cartilage.This article systematically summarized the new progress of the traditional growth factors,emphatically introduced the new discovered growth factors and some synthetic compounds and inorganic particles,which can induce stem cells into cartilage.Finally classified the different sources of stem cells and its suitable growth factors,and gave an outlook of the next research direction of growth factors.
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Objective To report the clinical efficacy of Kirschner wire combined with external fixator in the treatment of open comminuted distal tibiofibular fractures according to the concept of damage control orthopaedics.Methods A case series study was done on the clinical data of 15 open comminuted distal tibiofibular fractures which had been treated with kirschner wire combined with external fixation from January 2015 to August 2018 at Department of Orthopedics,Affiliated Hospital to Logistics College of Chinese People's Armed Police.They were 12 men and 3 women,aged from 27 to 62 years (mean,46.5 years).By the Gustilo classification,there were one case of type Ⅰ,4 cases of type Ⅱ,7 cases of type Ⅲ A,2 cases of type ⅢB and one case of type ⅢC.All the patients were treated with emergency debridement,tibial fixation using external fixator and fibular fixation using kirschner wire,followed by vacuum sealing drainage(VSD).Effective anti-inflammatory and other comprehensive treatments were given postoperatively.Regular follow-up was conducted to observe fracture healing and complications like osteomyelitis and bone disconnection.At the final follow-up,the American Orthopaedic Foot Ankle Society (AOFAS) ankle-hindfoot scale was used to evaluate the ankle function.Results All the patients were followed up for 12 to 18 months (mean,12.8 months).Primary bone union was achieved in 13 cases (86.7％),delayed healing observed in one case (6.7％) and bone nonunion in one case (6.7％).No osteomyelitis occurred.By the AOFAS ankle-hindfoot scale,the ankle function was rated as excellent in 9 cases,as good in 4,as fair in one and as poor in one.Conclusions For patients with open comminuted distal tibiofibular fracture,treatment should be conducted according to the concept of damage control orthopaedics.After early thorough debridement,the tibia should be fixated using external fixator and the fibula using kirschner wire,followed by VSD,leading to economical cost and satisfactory clinical efficacy.
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Objective To investigate the effect of acupuncture combined with hyperbaric oxygen therapy on neurological function and daily living ability of patients with cerebral hemorrhage. Methods From January 2014 to June 2017,one hundred and twenty-three patients with cerebral hemorrhage which hospitalized in the Department of Neurosurgery of Hebei Provincial Corps Hospital were selected and randomly divided into three groups: acupuncture group, acupuncture + hyperbaric oxygen group ( combined group ) and control group. The acupuncture group was given acupuncture on the basis of routine medical treatment after minimally invasive surgery treatment; the combined group was treated with acupuncture treatment as well as hyperbaric oxygen therapy after minimally invasive surgery; the control group was only treated with conventional medical therapy without any special treatment. The scores of nerve function defect,Fusl-Meyer motor function assessment scale,daily living ability score,cognitive function score,Glasgow coma scale at the 40th day of admission were evaluated and compared respectively,and the clinical effect were evaluated as well. Results After treatment, the NHISS score of the control group,the acupuncture group and the combined group decreased in turn. The score of Fusl-Meyer exercise function rating scale, the daily living ability score, the cognitive function score and the Glasgow coma scale were increased in turn, and the differences were statistically significant ( F=276. 620, 76. 050,31. 770,116. 598,33. 745,P<0. 01) . The total effective rate of the control group,acupuncture group and combined group increased sequentially (61％,76％,90％),and the difference was statistically significant (χ2=18. 547,P<0. 01) . Conclusion Acupuncture therapy for patients with cerebral hemorrhage can effectively promote the improvement of nerve function, daily living ability and prognosis. Acupuncture combined with hyperbaric oxygen can get more obvious therapeutic effect.
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Objective To explore the effect of hypergravity on morphology and osteogenesis function of preosteoblast MC3T3-E1 ceils.Methods The cultured MC3T3-E1 cells under hypergravity by different loading forces were divided into five groups,including control group,5 g group,10 g group,15 g group and 20 g group.The experimental groups were loaded for 30 min each time in 3 successive days,and the control group with no g-value was synchronously exposed to the same surrounding.The morphology of cytoskeletal protein was observed by phalIoidin staining,The alkaline phosphatase (ALP) content was examined by ALP activity assay kit,the gene expression of ALP,collagen Ⅰ (Col Ⅰ),osteocalcin (OC),runt-related transcription factors (Runx2) was measured by real-time quantitative PCR,and the protein expression of Col Ⅰ and OC was tested by Western blotting.Results Under the condition of hypergravity,cell body of osteoblast became thinner,but its surface area increased significantly;with the structure of skeletal arrangement becoming loose,actin microfilament structure reduced so that the orderly arrangement of actin-like dispersion lowered.The gene expressions of related indicators of osteogenic differentiation including ALP,Col][,OC,Runx2 were significantly up-regulated,which was the same as Col Ⅰ protein and OC protein after hypergravity loading.A very minute quantity of small red-orange nodules was found in the control group,while the cells in experimental groups after hypergravity loading obviously formed various sizes of red-orange nodules.Conclusions Under hypergravity,changes in osteoblast morphology can be triggered by rearrangements of skeletal structure.Furthermore,osteoblast maturation and differentiation can be stimulated effectively by up-regulating differentiation-related gene and protein expressions.
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Objective To explore the surgical feasibility and clinical efficacy of one-stage anterior-posterior approaches in treatment of severe fracture and dislocation of lower cervical spine in "beach chair position".Methods Sixteen male cases of severe fracture and dislocation of lower cervical spine and with a mean age of 49.8 years (range,36-78 years) treated surgically from May 2012 to May 2016 were analyzed retrospectively by using case series study.The segment of injury was C4-5 in 4 cases,C5-6 in 7 and C6-7 in 5.The degree of spinal cord injury according to the American Spine injury Association (ASIA) score was Grade A in 4 cases,Grade B in 7 and Grade C in 5.Sub-axial injury classification (SLIC) score was 8 points in 9 cases and 9 points in 7.After a general anesthesia,a ring with a hole was hanged on patient's head before the operation.Then,under the protection of hole traction,the upper of operating bed was swung up slowly,so that the patient was restricted in vertical "beach chair position" with traction on the halo in order to immobilize the head and partially reduce the kyphotic deformity.Routine cervical anterior-posterior approach was done with the exposure of damaged section of the front and rear structure.Pedicle screw system or lateral mass screw displacement was conducted.Anterior intervertebral discectomy or fracture vertebral was performed,using collaborative reset prying method before and after the road.In the front of intervertebral cage or titanium net support bone graft,rear pedicle screws or lateral mass screws fixation and bone graft fusion were implemented.The operation time and blood loss were recorded.The healing of the wound was observed.The recovery of neurological function was evaluated according to the ASIA grade.Postoperative review X-ray,CT and MRI were done to evaluate the reset and bone graft in position and fusion.Results All the surgeries were done well without aeroembolism and other related complications.The mean operative time was 153 minutes (range,150-180 minutes),and the mean amount of blood loss was 543 ml (range,400-800 ml).Sixteen cases were followed-up from 6 to 24 months (mean 13.7 months).All the incision were healed at Ⅰ stage.Spinal cord function did not aggravate.The ASIA grade was improved with an average of one to two Grades 6 months after surgery.Postoperative X-ray and CT confirmed that graft object position was favorable and cervical sequence was recovered well.The Cobb angle decreased from (23.6 ± 5.3) ° preoperatively to (4.0 ± 0.4)°postoperatively,and the translational displacement of vertebral body was restored into (2.7 ±0.4) mm (P ＜ 0.01) from (10.9 ± 1.6) mm before operation.The cervical spinal canal was not obstructed and the cervical spinal cord was relieved,showed by MRI.Conclusions One-stage anterior-posterior approaches for severe fracture and dislocation of lower cervical spine circumferential reconstruction in "beach chair position" is a beneficial and effective method,without the need of changing positions in a collaborative reduction and fixation.The method can reduce the interference of spinal cord,shorten the operation time and save anterior extra fixation.
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Objective To explore the surgical feasibility and clinical efficacy of one-stage anterior-posterior approaches in treatment of severe fracture and dislocation of lower cervical spine in "beach chair position".Methods Sixteen male cases of severe fracture and dislocation of lower cervical spine and with a mean age of 49.8 years (range,36-78 years) treated surgically from May 2012 to May 2016 were analyzed retrospectively by using case series study.The segment of injury was C4-5 in 4 cases,C5-6 in 7 and C6-7 in 5.The degree of spinal cord injury according to the American Spine injury Association (ASIA) score was Grade A in 4 cases,Grade B in 7 and Grade C in 5.Sub-axial injury classification (SLIC) score was 8 points in 9 cases and 9 points in 7.After a general anesthesia,a ring with a hole was hanged on patient's head before the operation.Then,under the protection of hole traction,the upper of operating bed was swung up slowly,so that the patient was restricted in vertical "beach chair position" with traction on the halo in order to immobilize the head and partially reduce the kyphotic deformity.Routine cervical anterior-posterior approach was done with the exposure of damaged section of the front and rear structure.Pedicle screw system or lateral mass screw displacement was conducted.Anterior intervertebral discectomy or fracture vertebral was performed,using collaborative reset prying method before and after the road.In the front of intervertebral cage or titanium net support bone graft,rear pedicle screws or lateral mass screws fixation and bone graft fusion were implemented.The operation time and blood loss were recorded.The healing of the wound was observed.The recovery of neurological function was evaluated according to the ASIA grade.Postoperative review X-ray,CT and MRI were done to evaluate the reset and bone graft in position and fusion.Results All the surgeries were done well without aeroembolism and other related complications.The mean operative time was 153 minutes (range,150-180 minutes),and the mean amount of blood loss was 543 ml (range,400-800 ml).Sixteen cases were followed-up from 6 to 24 months (mean 13.7 months).All the incision were healed at Ⅰ stage.Spinal cord function did not aggravate.The ASIA grade was improved with an average of one to two Grades 6 months after surgery.Postoperative X-ray and CT confirmed that graft object position was favorable and cervical sequence was recovered well.The Cobb angle decreased from (23.6 ± 5.3) ° preoperatively to (4.0 ± 0.4)°postoperatively,and the translational displacement of vertebral body was restored into (2.7 ±0.4) mm (P ＜ 0.01) from (10.9 ± 1.6) mm before operation.The cervical spinal canal was not obstructed and the cervical spinal cord was relieved,showed by MRI.Conclusions One-stage anterior-posterior approaches for severe fracture and dislocation of lower cervical spine circumferential reconstruction in "beach chair position" is a beneficial and effective method,without the need of changing positions in a collaborative reduction and fixation.The method can reduce the interference of spinal cord,shorten the operation time and save anterior extra fixation.
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Objective To systematically evaluate the efficacy and safety of posterior short segment and long segment pedicle screw internal fixation in the treatment of thoracolumbar burst fracture. Methods By searching the database, including PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, a comprehensive study was carried out to make a comparison between the posterior short segment and the long segment pedicle screws internal fixation in treatment of thoracolumbar burst fracture, and Meta analysis was performed. Results A total of 14 related studies and 658 patients were enrolled in the study, including 320 patients in short segment group and 338 cases in long segment group, and Meta analysis was performed. The results suggested that there was no significant difference between the short segment group and the long segment group in terms of the deformity angle of the injured vertebra measured after operation and at the last follow?up, and sagittal index at the last follow?up ( MD=-0. 22,95%CI -2. 73,2. 28,P=0. 86;MD=-0. 28,95%CI -2. 23,1. 67, P=0. 78;MD=0. 47, 95%CI -3. 45, 4. 39, P=0. 81 ) . Besides, both groups had no statistical difference in post?operative COBB angle,anterior vertebral height and compression rate of injured vertebrae ( MD=0. 21,95%CI -0. 65,1. 06,P=0. 64; MD=-0. 46,95%CI -1. 40,0. 49,P=0. 34; MD=0. 47,95%CI -2. 28, 3. 21, P= 0. 74 ) , while the differences in COBB angle, anterior vertebral height, compression rate, correction loss were statistically significant at the last follow?up (MD=5. 11,95%CI 2. 81,7. 40,P<0. 0001;MD=-11. 89,95%CI-15. 28,-8. 50,P<0. 00001;MD=6. 46,95%CI 3. 85,9. 07,P<0. 00001) . There was no significant difference in VAS scores and the ODI scores between the two groups at the last follow?up ( MD =0. 01,95%CI -0. 15,0. 17,P=0. 9; MD=-0. 47,95%CI -2. 68,1. 74,P=0. 86),while the two groups showed statistically significant difference in fixation failure ( RR = 0. 08, 95%CI 0. 01, 0. 15, P = 0. 02 ) . Conclusion Posterior long segment pedicle screw internal fixation is more effective in treating thoracolumbar burst fracture than short segment surgery. It can reduce the COBB angle,restore the anterior height of the injured vertebra,and decrease the anterior vertebral pressure.
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Objective To investigate the chondrocyte proliferation and extracellular matrix biosynthesis of electrospun PCL scaffolds seeded with rabbit chondrocytes under flow perfusion culture in vitro.Methods Nonwoven PCL microfiber mats were fabricated,and contra-aperture cylindrical glass equipment as a perfusion bioreactor was designed and manufactured on our own.The experiment included peffusion culture group and static culture group.Primary chondrocytes were isolated from the knee joints of two-month-old New Zealand white rabbits and seeded into scaffolds.The scaffold-cell complexes were harvested at 3,7,and 14 days of culture for scanning electron micrograph (SEM) analysis,biochemical assay,real-time PCR and histology analysis.Results Electrospun PCL scaffolds were composed of microfibers with a diameter of 1.67±0.76 μm and pores with a diameter of 17.65±7.11 μm.SEM showed a better cell proliferation with typical morphology of chondrocytes under perfusion culture.At 7 days of culture,DNA content in perfusion culture group was higher than in static culture group.At 3,7 and 14 days of culture,compared with the static culture group,glycosaminoglycan (GAG) content and GAG/DNA ratio in perfusion culture group were higher,and the differences were statistically significant.At 14 days of culture,real-time PCR showed aggrecan and collagen type Ⅱ gene expression and collagen type Ⅱ to collagen type Ⅰ ratio were higher in perfusion culture group than in static culture group; HE and safranin O staining showed a significant cell proliferation,infiltration,as well as extracellular matrix biosynthesis in perfusion culture group.Conclusion Under flow perfusion culture,the electrospun PCL scaffolds seeded with rabbit chondrocytes can enhance chondrocyte proliferation and extracellular matrix biosynthesis,which is a promising method for cartilage tissue engineering.
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ObjectiveTo explore the effect of osteoarthritis (OA) chondrocytes and normal chondrocytes on the chondrogenesis of bone marrow mesenchymal stem cells(BMSCs) in self designed co-culture system. MethodsRabbit BMSCs and chondrocytes were isolated and expanded in vitro. OA chondrocytes were harvested from the rabbit of established osteoarthritis model. We made a BMSCs-low melting agarose constructs, then put it onto the self-made 6 well plates lattice assembly for co-culture with chondrocytes. The groups were divided into Normal P0-BMSCs, Normal P3-BMSCs, OA PO-BMSCs, OA P3-BMSCs and BMSCs (control) group. At 3, 7, 14 day culture, cultured cells in all groups were collected for real-time PCR, glycosaminoglycan (GAG) content, cytoactive detection, and histological observation. ResultsType Ⅱ collagen gene expression was up-regulated in group Normal PO-BMSCs, which showed 5.1-, 7.2-, 11.2-fold increase over that of control group at 3, 7, 14 days, respectively. Type Ⅰ, Ⅱ collagen and aggrecan gene expressions were not obviously up-regulated. In group OA P3-BMSCs, type Ⅰ collagen gene expression level lower than the control group in 3, 7, 14 day. In normal PO-BMSCs, GAG content showed 2.59-fold increase over that of the control group. GAG content of group OA PO-BMSCs and control group showed no significant differences.Others groups showed significant differences in comparison with the control group(P＜0.05). Alcian stain showed positive in all groups. The normal PO-BMSCs group showed the darkest blue-stained. Conclusion Rabbit normal PO chondrocytes and rabbit OA P0 chondrocytes significantly enhanced chondrogenic differentiation of rabbit BMSCs. The secreted morphogens of the rabbit normal P3 chondrocytes and rabbit OA P3 chondrocytes do not have a significant effect on chondrogenic differentiation of rabbit BMSCs.
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BACKGROUND:During semi-knee arthroplasty,only the design and fabrication performed according to patient's injury can implement the good matching between prosthesis and joint surface,which is difficult to perform by conventional design and fabrication.OBJECTIVE:To develop a custom design and rapid fabrication method for artificial semi-knee joint based on computer aided design (CAD) and rapid prototyping (RP) techniques,and to evaluate the clinical application value of semi-knee arthroplasty and the role of CAD/RP in the design and fabrication of prosthesis.DESIGN,TIME AND SETTING:A custom design and fabrication of prosthesis and its clinical application was performed in the Xijing Hospital Affiliated to Fourth Military Medical University of Chinese PLA & Institute of Advanced Manufacturing Technology,Xi'an Jiaotong University & the State Key Laboratory of Materials and Mechanics,College of Mechanical Engineering,Xi' an Jiaotong University between January 2002 and December 2005.PARTICIPANTS:A 14-year-old male patient with osteosarcoma in the lower segment of the right femur was recruited into this study due to recurred osteosarcoma one year after surgery.Tumorectomy,large allogenic bone transplantation,and custom-made semi-knee arthroplasty were to be performed in this patient.A written informed consent was obtained from his relatives.METHODS:Clinical imageological data of the patient in terms of CT scanning and three-reconstruction were taken as data source.Data regarding joint shape were acquired by image processing technique.Joint contour was reconstructed by NRRBS algorithm using Surfacer software.Through the use of computer,the three-dimensional design of semi-knee joint prosthesis and its auxiliary devices was conducted.Subsequently,prosthetic prototype was fabricated by RP technique and prosthetic products were made by precise casting methods.Finally,the manufactured prosthesis was installed into the allogenic bone with the help of aiming device and was transplanted into the affected limb following distal locking.MAIN OUTCOME MEASURES:Error analysis of joint contour reconstructed using the Surfacer software; assembling of manufactured joint prosthesis and auxiliary devices; X-ray examination results,joint space status,and range of motion of joint in flexion and extension positions following prosthesis replacement.RESULTS:All procedures were conducted within 1 week.The maximum difference between CAD model-related data and original data was less than 1 mm.In the flexion,extension,and rotation positions,joint prosthesis well matched tibial joint surface,with evenly distributed stress.The prosthesis and auxiliary manufactured by RP and precise casting techniques met the requirements of design and could be installed into large segment of allogenic bone.Prosthesis was precisely placed into the affected knee and could well match contralateral tibial joint surface with normal joint space.No adverse reactions were found and the patient could implement functional exercise.One-year follow-up results revealed that the patient acquired satisfactory therapeutic effects without dislocation and chronic pain.CONCLUSION:Semi-knee joint individually fabricated by CAD and RP techniques provides some clinical application vilues in specific cases.
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BACKGROUND: Bone morphogenetic protein-2 has been previously proved to not only stimulate and different bone tissue-derived cells, but also induce differentiation from cell strain into osteoblasts; however, direct application of bone morphogenetic protein has poor effects on repairing bone defects. OBJECTIVE: To study new bone formation in a rabbit model of avascular necrosis of the femoral head (ANFH) following recombinant human bone morphogenetic protein-2 (rhBMP-2)/fibrin sealant (FS) implantation combining with core decompression. DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at the Affiliated Hospital of Medical College of Chinese People’s Armed Police Force from January 2005 to December 2007. MATERIALS: Composite was made by rhBMP-2 and FS, and the final concentration of rhBMP-2 was 1 mg/L. METHODS: Animal models of ANFH were made by injecting hormone. The rabbits were randomly divided into three groups, including rhBMP-2/FS implantation group, rhBMP-2 implantation group, and core decompression alone group. MAIN OUTCOME MEASURES: Signal changes of femoral head and sclerotin were detected using MRI method; new bone formation was observed under optic microscopy; calcium content was measured using atomic absorrtion spectrophotometer. RESULTS: MRI indicated that new bone replaced primary bone defect channel at week 8 after rhBMP-2/FS implantation. A few of new bones were observed in the rhBMP-2 implantation group, and fiber tissue was still observed in the core decompression alone group. Morphology suggested that a great quantity of mature bone trabecula and plate-shaped bone replaced primary bone defect channel at week 8 after rhBMP-2/FS implantation. Bone defect was decreased in the rhBMP-2 implantation group, accompanying with a few of bone trabecula and blood capillary but a large quantity of fiber tissues. At week 8 after core decompression alone, bone defect was decreased, and a few of new bones were observed. Fiber tissue still existed in the center, and any bone tissue did not fill in it. Calcium content in the rhBMP-2/FS implantation group was greater than rhBMP-2 implantation group and core decompression alone group (P
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<p><b>OBJECTIVES</b>To construct new type of bone graft material by combining calcium phosphate cement (CPC) with bone morphogenetic protein (BMP), and then to detect its osteogenic activity.</p><p><b>METHODS</b>The surface of CPC and CPC/BMP composite were observed by scanning electron microscope (SEM). CPC and CPC/BMP pellets were separately implanted into the thigh muscle pouches of mice. Samples obtained at different times were tested by histological analysis, SEM, organic substance detection, and alkaline phosphatase (ALP) measurement to observe the induced ectopic bone formation.</p><p><b>RESULTS</b>Under SEM, the CPC and CPC/BMP composite was found to consist primarily of platy crystals, granular crystals and some small rod-like crystals with micropores about 10-50 microm in size. BMP about 1-5 microm in size was seen like micro globules distributing evenly in the micropores. Newly formed cartilage or bone was not found in the CPC group. In the CPC/BMP group, mesenchymal cells were proliferated and abundant cartilage was found in one week. Woven bone appeared at 2 weeks. New bone formation increased with bone marrow at 4 weeks. At 8 weeks, the implanted CPC/BMP became heterogeneous and a lot of collapsed granules were observed. At the end of 16 weeks, mature lamellar bone appeared and the volume of the implanted CPC/BMP became smaller. One week after implantation, the ALP increased evidently in the CPC/BMP groups and reached the highest level at the 4th week, which was about 168 U/L. The content of organic substance in specimens increased from 22% to 39% by the end of the 16th week, showing the continuous calcification and formation of new bone. SEM also showed that the CPC/BMP composite had good potentiality of ectopic bone induction, and the new bone formed accompanied by the slow degradation of the material.</p><p><b>CONCLUSION</b>The results of this study suggested that the CPC/BMP composite could be used as material for bone graft substitute.</p>
Subject(s)
Animals , Male , Mice , Bone Cements , Bone Morphogenetic Proteins , Pharmacology , Bone Substitutes , Pharmacology , Calcium Phosphates , Materials Testing , Mice, Inbred Strains , Osteogenesis , Prosthesis ImplantationABSTRACT
Objective To find the best sample collecting and template making methods. Methods The multiplex PCR results of three sample collecting methods and eight template making methods in malaria diagnosis were compared. Results Conserved blood sample collecting, and Na 3PO 4 template making were sensitive and simple. Conclusion Conserved blood of sample collecting and Na 3PO 4 in template making are the best methods in multiplex PCR diagnosis of malaria, and are worthy of wide use.
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Objective A new type of bone graft material was constructed by combining calcium phosphate cement(CPC) with bone morphogenetic protein(BMP). In order to evaluate the feasibility to use this material to repair the segmental bone defect in clinic, the ability of CPC was compared with CPC/BMP in bone defects reconstruction by animal experiments. Methods The model of 15 mm bone defect was established in the middle shaft of the radius in 60 rabbits, of which 30 defects were implanted with CPC/BMP composites, 22 implanted with CPC, and the other 8 rabbits served as control group. The specimens were harvested separately at the end of 2, 4, 8, 16 and 24 weeks after operation. In order to observe the formation of new bone and the degradation process of the material, a series of examinations were carried out including of radiography, histomorphology, serum detection, energy dispersion analysis X-ray(EDAX), scanning electron microscope(SEM),bone density detection, mechanical measurement and inorganic substance detection. The results of CPC group and CPC/BMP group were compared on the same condition. Results All the animals survived after operation, and no reactions of toxicity were found. New bone formation was observed to be increasing significantly in CPC/BMP group with the time of implantation. Only little new bone formed in CPC group and no healing was found in the control group. By the end of 24 weeks, new bone had bridged the gap between the proximal and distal fragments in CPC/BMP group. In histomorphological detection, chondrocytes were found at the 2nd week, and woven bone at 4th week in CPC/BMP group. Remodeling of new lamellar bone and absorption of the composite material were observed at the 16th week, and the mechanical strength of the composite material reached almost to normal level at the 24th week. Calcification was significantly higher in CPC/BMP group than that in CPC group examined by EDAX, new bone density detection and measurement of inorganic substance in specimens. During the repairing process of bone defect, the material degraded while new bone formed, the speed of degradation of CPC/BMP was evidently higher than that of CPC group. Moreover, in the process of CPC degradation, the concentration of calcium in serum increased, and the concentration of phosphate in serum kept unchanged. Conclusion The CPC/BMP composite has great potential in bone defects repairing and could be used as a material for bone graft substitute in clinical patients.