Objective To investigate the effect of deproteinated bone(DPB)-bone morphogenetic protein(BMP) complex on bone tunnel enlargement after anterior cruciate ligament reconstruction in rabbits.Methods A total of 96 adult New Zealand white rabbits were used in this study,and divided into 4 groups.In each group,we reconstructed the anterior cruciate ligaments of the animals using semitendinosus autograft.After the operation,DPB-BMP complex,DPB,or BMP was implanted into the femoral bone tunnel of the rabbits in three of the 4 groups.Another group that received neither DPB nor BMP served as a control.In 4,8,12,or 16 weeks after the implantation(6 rabbits in each group at each time point),we killed the animals to obtain the specimens of the femoral bone tunnel.Then the width of the tunnel was measured,and the percentage of its enlargement was calculated.Results In the DPB+BMP,DPB,BMP,and control groups,the bone tunnel was enlarged by(23.52?0.43)%,(34.83?0.52)%,(51.57?0.76)%,and(56.90?0.81)% in 4 weeks,(22.21?0.34)%,(35.35?0.46)%,(60.97?0.63)%,and(67.18?0.70)% in 8 weeks,(21.94?0.37)%,(33.01?0.41)%,(50.56?0.54)%,and(54.61?0.55)% in 12 weeks,and(20.96?0.35)%,(32.11?0.50)%,(49.29?0.66)%,and(53.31?0.59)% in 16 weeks,respectively.The rates of bone tunnel enlargement in the DPB+BMP group was the lowest at each time point(DPB+BMP group

Objective To compare the results of 3 methods to treat complete dislocation of acromioclavicular joint. Methods Three different surgical techniques were employed: Dewars procedure (in Group A of 32 cases),tension band wiring (in Group A of 44 cases), and Wolter plate fixation (in Group A of 20 cases). There were 81 males and 15 females, or totally 85 cases of acute dislocation and 11 chronic dislocation. Results 96 cases were followed up with an average period of 50 months. Acording to karlssons standards, in group A, 26 patients were assessed as good, 5 as fair and 1 as poor. In group B, 20 patients were assessed as good, 13 as fair and 11 as poor. In group C, 15 patients were assessed as good, 4 as fair and 1 as poor. There were differences between A and B, C and B. But there werent statistic differences between A and C. Conclusion The Dawers procedure is believed to be a good, simple and safe method to treat acromioclavicular joint dislocation, with no need of a second operation to remove the implant and with less complications.

Objective To investigate the characteristics of looped ankle injury caused by cord strangulation, seek proper treatment to decrease amputation rate, and restore limb function as much as possible. Methods Among the nine patients with looped strangulation ankle injury, 7 had both their anterior and posterior tibia arteries involved, while the other 2 patients had only their posterior tibial artery involved. There were 4 patinets suffered from combined open tibia and fibula fractures, 2 patients from close tibia and fibula fractures; and another 2 patients from external malleolus fracture. The interval from injury to treatment varied from 6 to 27 hours(average 12 hours). All patients were treated with surgical procedures as soon as possible, blood vesseles and nerve injuries were detected and anastomosis had been done if necessary. All fractures were fixed externally. Results The limbs of all 9 patients were salvaged successfully. Most function of the injured limbs were restored. Only one external malleolus fracture malunited and was treated successfully by subsequent osteotomy. Conclusion Emergent intervention is of great importance to looped ankle injury caused by cord strangulation. Once blood vessel or nerve injuries are suspected, surgical detection or anstomosis if neccessary, should be done as soon as possible. All the associated fractures should better be fixed externally, and in order to avoid "tourniquet effect"the injured skin should be incised as early as well. With proper limb salvage procedure, good or excellent result may be achieved even in the patient with a delayed diagnosis.

BACKGROUND:After peripheral nerve injury, to inhibit scar formation by drugs is the key to functional recovery. To reduce the amount of scar formation we designed a prednisolone-loaded film which can sustain drug release and good achievement in in vitro drug release test.
OBJECTIVE:To prepare the prednisolone implantable film and investigate its in vivo biocompatibility and safety.
METHODS:Prednisolone-loaded nanoparticles were first prepared with reverse micellar emulsion-solvent evaporation method, and the composite film and drug-loaded film were further prepared. Then, we investigated the in vivo biocompatibility of drug-loaded film through celltoxicity test, hemolysis test, acute systemic toxicity test, chronic systemic toxicity test.
RESULTS AND CONCLUSION:After cultured for 7 days, the relative growth rate of L929 mouse fibroblasts was 92.6%, showing no cytotoxicity. The hemolysis rate of the film was 0.59%, indicating that the material had no hemolysis action. No abnormal biological behaviors were seen in mice after intraperitoneal injection of film extracts, and there were no changes in liver and renal functions in rats. As il ustrated above, we can safely come to a conclusion that prednisolone-loaded film possesses good biocompatibility and can be safely used in the experiment of reducing the scar at sites of peripheral nerve repair.

Objective To explore the clinical effects of atlantoaxial pedicle screw instrumentation in treatment of intractable atlantoaxial dislocation in children. Methods A total of 7 patients with intractable atlantoaxial dislocations were treated with aflantoaxial pedicle screw instrumentation plus atlantoaxial bone grafting from June 2002 to January 2001. Results The dislocation in all patients reached complete reduction, with no complications. All patients were followed up for average 10 months (8-14 months). Radiographs showed successful bone fusion in all patients. Conclusion Atlantoaxial pedicle screw fixation and fusion is an effective method for treatment of intractable atlantoaxial dislocation in chil dren.

BACKGROUND:In recent years, the use of prednisolone has good achievements in functional recovery after peripheral nerve injury, but its short half-life, instable plasma concentrations and greater adverse reactions limit its clinical application. OBJECTIVE:To prepare prednisolone implantable films and to explore the sustained-release property of prednisolone implantable films. METHODS:Novel reverse micellar emulsion-solvent evaporation method was used to prepare nanoparticles which contains prednisolone, and we investigated the properties of prednisolone-loaded nanoparticles, including morphological form, diameter, drug loading, encapsulation efficiency, in vitro release properties. Then, composite film was prepared with the nanoparticles above and col agen, chitosan, soybean phosphatidylcholine. The properties of composite films, such as morphological form, the interaction among film materials, in vitro releasing curve, were investigated. RESULTS AND CONCLUSION:The prednisolone-loaded nanoparticles displayed favorable microstructure such as smooth surface, consistent diameters. The mean diameter of the nanoparticle was 500 nm and the max encapsulation efficiency of the nanoparticle was more than 90%. The nanoparticle displayed obvious sustained-release effect in vitro, but it exhibited a certain burst release phenomenon. We found that the nanoparticles were uniformly distributed inside and on the surface of the composite film;and the in vitro release rate of the film was slower and more stable than the nanoparticles. The composite film displayed favorable sustained-release effect with no burst release. From what we have il ustrated above, we can safely come to a conclusion that the prednisolone-loaded film possesses good sustained-release effects.

Objective To explore the perioperative management and surgical outcomes of fracture-dislocation of the upper cervical spine complicated with vertebral artery injury.Methods We retrospectively analyzed the clinical data of 19 patients diagnosed with fracture-dislocation of the upper cervical spine complicated with vertebral artery injury who had been treated at our department from January 2008 through December 2012.They were 14 males and 5 females,aged from 22 to 53 years (mean,35.2 years).All the patients had fractures of the atlas and/or axis,and disordered atlanto-axial relationship as well.According to Frankel grading system,8 cases were Grade D and 11 Grade E.The cervical posterior fixation with pedicle screws was adopted for all and hemostasis was conducted for those with bleeding from the broken vertebral artery.Their Frankel grade,Japanese Orthopedic Association (JOA) score and visual analogue scale (VAS) score were compared between preoperation and final follow-up.Results Intraoperative hemorrhage occurred in 2 patients from the injured vertebral artery.Hemostasis was achieved through direct tamponade with bone wax and gelatin sponge in one and through endovascular intervention after bleeding control by direct tamponade in another.Neither of them presented with symptoms of posterior circulation ischemia after operation.The mean operation time was 153.5 min,and the mean blood loss was 542.1 mL.All the patients were followed up for an average time of 28 months.Bony union was obtained in all after an average time of 13.5 weeks.Follow-ups revealed no ischemic stroke in this series.Symptoms of transient ischemic attack,like transient dizziness and blurred vision,appeared in 2 patients.At the final follow-up,all the patients were assessed as Frankel Grade E.Their mean JOA and VAS scores were significantly improved from 8.1 ± 1.2 and 7.0 ± 1.7 preoperatively to 12.7 ± 1.6 and 1.3 ± 1.2,respectively (P ＜ 0.05).Conclusions Angiography examination is routinely indicated for the patients with fracture-dislocation of the upper cervical spine perioperatively.Preoperative evaluation of the vertebral artery and its adjacent structures and effective intraoperative hemostasis can avoid uncontrollable bleeding during operation,reduce postoperative complications,and improve surgical outcomes.

BACKGROUND: Autologous bone graft was always applied to repair bony cavity defect produced by benign bone tumor.OBJECTIVE: Taking autogenous bone graft for repairing bony cavity defect caused by bone tumor or tumor-like pathological change as control standard, to observe transplantation of deproteined bovine cancellous bone combined with autogenous red marrow in occluding the residual cavity and the density of newly formed bone.DESIGN: A randomized grouping design, controlled observation SETTING: Department of Orthopaedics, the 175 Hospital of Chinese PLA PARTICIPANTS:We recruited 175 cases of bony cavity defect who received treatment in the Department of Orthopaedics, the 175 Hospital of Chinese PLA from July 1993 to July 1998. They were randomly assigned into two groups: experimental group and control group. There were 63 cases treated in the experimental group. The average disease-suffering time was (6.2±2.1) months and bone defect was (136±30) mm3. There were 62 cases treated in the control group. The average disease-suffering time was (6.1±2.3)months, and bone defect was (133±37) mm3.METHODS: Deproteined bovine cancellous bone combined with autogenous red marrow was transplanted in the experimental group and autologous bone graft was applied in the control group. We curetted tumor completely, cauterized the wound with alcohol of 0.95 volume fraction, then curetted the area of cauterization to make it bled. Bone graft was applied.The quantity of implanted bone should be abundant, and disposed compactly. The X-ray films of the first week after operation were used as a standard for density of new bone growth. X-ray films were taken at the 3rd,6th and 8th months postoperatively, and the X-ray films of the eighth months after operation were used as a standard.MAIN OUTCOME MEASURES: To compare the bone union in two groups with a standard of residual cavity occluding and density of bone growth.RESULTS: All patients were followed up for an average of 20 months.One case was lost six months after operation. And two cases were lost eighteen months after operation respectively in the experimental group and control group. After 8 months of operation, residual cavities of bone defect of 44 cases in experimental group and 46 cases in control group were disappeared. Palingenetic bone fused with left bone organization. Its density was the same as or higher than normal bone organization. Residual cavities of 12 cases in experimental group and 10 cases in control group were disappeared basically. The density of palingenetic bone was approximate to normal bone organization. To compare with autologous bone graft, deproteined bovine cancellous bone and an autogenous red marrow had an identical effect for repairing bony cavity defect.CONCLUSION: Bony cavity defect produced by benign bone tumor is often repaired by bone transplantation. To explore the substitutable grafting materials of autogenous bone in this study, a composite material composed of deproteined bovine cancellous bone and an autogenous red marrow (DBCAM) is applied to repair the bony cavity defect.

Objective To develop and apply portable bracket of lower limb in operation of tibia interlocking intramedullary nail. Methods Portable bracket of lower limb is composed of two fir panels and support structure. The level of support and the knee flexion is controlled with it. It is used in preoperative high-pressure disinfection, and then trouble limb is placed on the bracket to complete operation of tibia interlocking intramedullary nail. Results The applications save labor, reduce iatrogenic injury, make for union of fracture and avoid radiation damage of staff. No one is used to lift up leg in operation procedure and X-ray examination. Conclusion Potable bracket of lower limb has advantages in simple production, low cost, labor-saving, minimally invasive surgery wound and so on.

BACKGROUND: After internal fixation is applied to femoral shaft fracture with medial cortical defect, the fixation device is often bended and broken due to the stress on it. So far, reliable methods have not been found to solve this problem in clinic.OBJECTIVE: To evaluate the biomechanical stability of the allograft bone plate after a bony defect of the medial cortex is reconstructed with allograft bone plate.DESIGN: A randomized controlled experimental study.SETTING: This trial was conducted in the Department of Orthopaedics, the 175 Hospital of Chinese PLA, and Laboratory of Biomechanics, First Military Medical University of Chinese PLA.PARTICIPANTS: This trial was conducted in Laboratory of Medical Biomechanics, First Military Medical University. MTS858 Biomix biomaterial testing machine was used to simulate model of femoral shaft fracture on 3male adult femurs donated voluntarily by their relatives, aged 23, 24 and 28years old.INTERVENTIONS: The fracture model of medial cortical defect was made in the femurs. Different kinds of fixation were applied and the results were compared between fixated femurs and the normal ones. The fixations included steel plate fixation(fixation for group 1 ), steel plate with allograft bone plate fixation(fixation for group 2), steel plate with allograft bone plate fixation and reduction of the medial cortical fragment(fixation for group 3).MAIN OUTCOME MEASURES: The vertical compression displacement under 500 N load, three-point bending strength under 10 N and anti-torsional angle under 300 N load are all measured.RESULTS: The vertical compression displacement and three-point bending strength of the control group were insignificantly different from those of the fixation group 3 ( P ＞ 0.05), but significantly different from those of the fixation group 1 and 2 ( P ＜ 0.05). The anti-torsional angle of the control group was significantly different from that of the three fixation groups( P ＜ 0. 05) . The result of fixation in fixation group 1 was the worst, better in fixation group 2and the best in fixation group 3.CONCLUSION: When there is a medial cortical defect in the femur, reconstruction with a bone plate can recover the integrity of the femoral medial cortex, and the successful rate of the plate internal fixation is increased.