Mid-term outcomes of primary constrained condylar knee arthroplasty for severe knee deformity / 华中科技大学学报（医学）（英德文版）

This study aimed to examine the clinical and radiographic outcomes of primary total knee arthroplasy (TKA) with use of NexGen® Legacy® Constrained Condylar Knee (CCK) prosthesis for severe knee deformity. Clinical data of 46 patients (48 knees in total, aged 61 years on average) with severe knee deformity who underwent TKA with NexGen® Legacy® CCK prosthesis between December 2007 and February 2012 were retrospectively analyzed. There were 34 knees with severe valgus with incompetent medial collateral ligament, 11 knees with severe flexion contracture with inability to achieve knee balancing in flexion and extension by posterior soft tissue release, 2 knees with Charcot arthritis with severe varus and bone loss, and 1 with traumatic osteoarthritis with severe varus and ligamentous instability. The mean duration of follow-up was 71 months (range 40-90 months). The New Knee Society scoring (NKSS) system and the Hospital for Special Surgery (HSS) score were used to evaluate the functional and clinical outcomes. Visual Analogue Scale (VAS) was used for pain measurement and Knee Society criteria for evaluation of radiological images. The results showed that, in the total 48 knees, 1 case of loosening due to short-stem tibial component at 3 months post-operatively underwent revision. The 6-year prosthesis survival rate in this cohort was 97.9%. There was no component infection occurring within 6 years. Significant post-operative improvements were found in NKSS and HSS scores. Patient satisfaction was significantly increased. Pain score was decreased significantly. Total functional score was improved from 31.46±11.43 to 86.42±8.87, range of motion (ROM) from 42.42°±23.57° to 95.31°±23.45° and the flexion contracture from 5.31°±7.87° to 0.92°±1.80°. Preoperative radiographic study showed excessive valgus (≥7°) in 37 knees, and varus deformity in 3 knees. Post-operative femorotibial alignment was valgus 3.88°±1.76° in 48 knees. Antero/posterior (A/P) view of X-ray films showed 4 radiolucent lines (RLL) in 48 tibial components. It was concluded that TKA with CCK is effective for the treatment of the severe unstable knee that cannot be balanced by soft tissue.

Mid-term outcomes of primary constrained condylar knee arthroplasty for severe knee deformity / 华中科技大学学报（医学）（英德文版）

This study aimed to examine the clinical and radiographic outcomes of primary total knee arthroplasy (TKA) with use of NexGen® Legacy® Constrained Condylar Knee (CCK) prosthesis for severe knee deformity. Clinical data of 46 patients (48 knees in total, aged 61 years on average) with severe knee deformity who underwent TKA with NexGen® Legacy® CCK prosthesis between December 2007 and February 2012 were retrospectively analyzed. There were 34 knees with severe valgus with incompetent medial collateral ligament, 11 knees with severe flexion contracture with inability to achieve knee balancing in flexion and extension by posterior soft tissue release, 2 knees with Charcot arthritis with severe varus and bone loss, and 1 with traumatic osteoarthritis with severe varus and ligamentous instability. The mean duration of follow-up was 71 months (range 40-90 months). The New Knee Society scoring (NKSS) system and the Hospital for Special Surgery (HSS) score were used to evaluate the functional and clinical outcomes. Visual Analogue Scale (VAS) was used for pain measurement and Knee Society criteria for evaluation of radiological images. The results showed that, in the total 48 knees, 1 case of loosening due to short-stem tibial component at 3 months post-operatively underwent revision. The 6-year prosthesis survival rate in this cohort was 97.9%. There was no component infection occurring within 6 years. Significant post-operative improvements were found in NKSS and HSS scores. Patient satisfaction was significantly increased. Pain score was decreased significantly. Total functional score was improved from 31.46±11.43 to 86.42±8.87, range of motion (ROM) from 42.42°±23.57° to 95.31°±23.45° and the flexion contracture from 5.31°±7.87° to 0.92°±1.80°. Preoperative radiographic study showed excessive valgus (≥7°) in 37 knees, and varus deformity in 3 knees. Post-operative femorotibial alignment was valgus 3.88°±1.76° in 48 knees. Antero/posterior (A/P) view of X-ray films showed 4 radiolucent lines (RLL) in 48 tibial components. It was concluded that TKA with CCK is effective for the treatment of the severe unstable knee that cannot be balanced by soft tissue.

Preparation and in vitro evaluation of DMAB-modified PLGA nanoparticles loading tetrandrine / 中草药

Objective: The study aims at preparing the didodecyldimethylammonium bromide (DMAB)-modified PLGA nanoparticles (NPs) loading tetrandrine (Tet) (DMAB-Tet-PLGA-NPs) and investigating the preparation process, physicochemical characterization, in vitro cytotoxicity, and particle cellular uptake. Methods: DMAB-Tet-PLGA-NPs were prepared by the emulsion solvent diffusion method and the preparation process was optimized with the uniform design experiment. The drug loading, entrapment efficiency (EE), and in vitro drug release were studied to evaluate the drug-loading property. The in vitro cytotoxicity against human lung cancer cell A549 was measured by the standard MTT assay. The particles cellular uptake in A549 was evaluated by qualitative and quantitative methods. Results: DMAB-Tet-PLGA-NPs in the mean size of (205.40±2.66) nm with spherical shape and showed positive surface charge. Drug loading and EE were (2.130±0.035)% and (50.780±3.253)%, respectively. DMAB-Tet-PLGA-NPs could retard drug release in pH 7.4 release media and the cumulative release was up to 64.56% over 48 h. And DMAB-Tet-PLGA-NPs showed the significant dose-and time-dependent cytotoxicity of Tet in vitro and well cellular uptake by A549. Conclusion: DMAB-Tet-PLGA-NPs shows the good EE, uniform particle size, and could retard drug release in vitro. And DMAB-Tet-PLGA-NPs shows the significant cytotoxicity in vitro and well cellular uptake by A549.

Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects.</p><p><b>METHODS</b>Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation.</p><p><b>RESULTS</b>The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone formation rate and antibending strength of group A was significantly higher than those of group B and C. The defects in blank control were not healed.</p><p><b>CONCLUSIONS</b>The hBMP2 gene activated nanobone putty exhibited osteoinductive ability, and had a better bone defect repair capability than that of nanobone putty only.</p>

Assessment of the expression profile during the entochondrostosis of vascular endothelial growth factor in bone morphogenetic protein 2 induced osteogenesis / 中华外科杂志

<p><b>OBJECTIVES</b>To examine the gene expression profile of bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF) during entochondrostosis of mice and explore the expression rules and effects between BMP-2 and VEGF, and to detect the expression of VEGF in BMP-2 induced entochondrostosis in vivo.</p><p><b>METHODS</b>cDNA microarray technique with 34,000 genes was used to analyze the gene expression profiles during entochondrostosis in the limbs of mice embryo from E10 to E14. Pathway analysis of BMP-2 and VEGF was performed with GCOS1.2 software. An experimental model of femoral muscular pouch in 20 mice was adopted. The expression of VEGF was examined by in situ hybridization method and immunohistochemical method in BMP-2 induced entochondrostosis in vivo.</p><p><b>RESULTS</b>The expression signals of VEGF mRNA and VEGF appeared in cytoplasm during condensation of mesenchymal cell. As the mesenchymal cells differentiated into precartilage, the expression signals decreased in mesenchymal cells, but increased in chondrocytes and kept getting denser in the process of cartilage maturity. The peak expression of VEGF mRNA and VEGF in the experimental group appeared on the 14th day, accompanied by numerous hypertrophic chondrocytes. When mature cartilage calcified and new bone trabecula formed, the expression of VEGF mRNA and VEGF decreased in chondrocytes, but still expressed moderately in the osteoblasts and osteocytes.</p><p><b>CONCLUSIONS</b>The finding reveals a complex pattern of gene coexpression of BMP-2 and VEGF during the critical period of entochondrostosis. It's feasible for the clinical application of BMP-2 in orthopedics.</p>

Vertebral plate regeneration induced by radiation-sterilized allogeneic bone sheets in sheep / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the effects and mechanism of radiation-sterilized allogeneic bone sheets in inducing vertebral plate regeneration after laminectomy in sheep.</p><p><b>METHODS</b>Twelve adult male sheep (aged 1.5 years and weighing 27 kg on average) provided by China Institute for Radiation Protection underwent L3-4 and L4-5 laminectomy. Then they were randomly divided into two groups: Group A (n=6) and Group B (n=6). The operated sites of L4-5 in Group A and L3-4 in Group B were covered by "H-shaped" freeze-drying and radiation-sterilized allogeneic bone sheets (the experimental segments), while the operated sites of L3-4 in Group A and L4-5 in Group B were uncovered as the self controls (the control segments). The regeneration process of the vertebral plate and the adhesion degree of the dura were observed at 4, 8, 12, 16, 20 and 24 weeks after operation. X-ray and CT scan were performed in both segments of L3-4 and L4-5 at 4 and 24 weeks after operation.</p><p><b>RESULTS</b>In the experimental segments, the bone sheets were located in the anatomical site of vertebral plate, and no lumbar spinal stenosis or compression of the dura was observed. The bone sheets were absorbed gradually and fused well with the regenerated vertebral plate. While in the control segments, the regeneration of vertebral plate was not completed yet, the scar was inserted into the spinal canal, compressing the dura and the spinal cord, and the epidural area almost disappeared. Compared with the control segments, the dura adhesion degree in the experimental regenerated segments was much milder (P less than 0.01), the internal volume of the vertebral canal had no obvious change and the shape of the dura sack remained well without obvious compression.</p><p><b>CONCLUSIONS</b>Freeze-drying and radiation-sterilized allogeneic bone sheets are ideal materials for extradural laminoplasty due to their good biocompatibility, biomechanical characteristics and osteogenic ability. They can effectively reduce formation of post-laminectomy scars, prevent recurrence of post-laminectomy spinal stenosis, and induce regeneration of vertebral plates.</p>

Effect of human bone morphogenetic protein-2 on vascular endothelial growth factor expression in fetal mouse osteoblasts / 中华创伤骨科杂志

Objective To investigate effects of different doses of recombinant human bone morphogenetic protein-2 (rhBMP-2) on vascular endothelial growth factor (VEGF) expression in fetal mouse osteoblasts.Methods Calvaria osteoblasts of fetal mice of 19 days were cultured.The effects of rhBMP-2 at different doses and different action times on VEGF expression patterns in fetal mouse osteoblasts were observed with reverse transcrip- tion-polymerase chain reaction (RT-PCR) and Western blot staining.Results In the present study,RT-PCR detected a steady expression of VEGF mRNA in the control fetal mouse osteoblasts.The levels of VEGF mRNA increased in an apparent biphasic manner with a maximum stimulation (about 2-fold above the control,P＜0.05 ) in both VEGF mRNA species observed at 300 ng/mL of rbBMP-2.After 48 h of rhBMP-2 treatment,the VEGF mRNA levels approached those in the control.The VEGF mRNA levels appeared to be biphasic in rhBMP-2-treated cultures,showing peak induction at 3 and 24 h and remaining elevated at 48 b.Compared with the individual control value at each time point,an apparent maximum increase (about 2.5-fold above the control,P＜0.05) occurred at 6 h.The second peak induction,about 2-fold above that in the control,occurred at about 36 h.Conclusions The expression of VEGF mRNA is steady in the control fetal mouse osteoblasts.RhBMP-2 can promote the expression of VEGF in dose-dependent and time-dependent manners.

Salvage of failed treatment of proximal femoral fractures with total hip replacement / 中华创伤骨科杂志

Objective To analyze the causes for failed treatments of proximal femoral fractures and to evaluate the curative results of total hip replacement(THR)to salvage the failures.Methods A retrospective study was conducted for 23 consecutive cases of THR to salvage failed treatments of proximal femoral fractures from February 2002 to April 2005.There were 17 cases of femoral neck fracture,five cases of intertrochanteric frac- ture,and one case of femoral head fracture.Results Inadequate reduction after inadequate fixation,incorrect materials or technical errors in internal fixation were the most significant reasons for the failure of early treatment. Twenty-one of the 23 patients were available for fullow-up that ranged from 8 to 46 months(mean,32 months). No such complications as wound infection,hip dislocation,prosthesis breakage or deep venous thrombosis were found.Their mean Harris score increased from 48.3 preoperatively to 87.6 postoperatively.Condusions Re- duction,internal fixation,and fixation technique are very important to treatments of proximal femoral fractures. High energy trauma in young patients and osteoporosis in old patients make treatment of proximal femoral fractures even more difficult.THR is a satisfactory and safe way to salvage a failed treatment of proximal femoral fracture.