T8钢冷剪下料时端部断裂及坏头原因分析

T8钢用冷剪下料时,A厂钢材出现端部开裂及坏头的比例较大,B厂材料出现端部开裂及坏头的比例较小。分别选取A厂与B厂相同规格的T8钢,对比分析钢的化学成分、非金属夹杂物、布氏硬度、金相组织。分析结果表明:1)造成材料剪切端面裂纹的原因是钢材硬度偏高;2)A厂T8钢材质硬度偏高的主要原因是钢中的碳含量偏高,加上钢材终轧温度低,钢材轧后在冷床上停留时间长,钢材堆冷时温度偏低,与钢材的内部质量无关。

体外冲击波联合股骨头坏死愈胶囊治疗早期股骨头坏死30例临床观察

目的:观察体外冲击波联合股骨头坏死愈胶囊治疗早期股骨头坏死的临床疗效。方法:将60例早期股骨头坏死患者按照随机数字表法分为治疗组和对照组,每组30例。对照组给予体外冲击波治疗;治疗组在对照组治疗基础上联合口服股骨头坏死愈胶囊。2组均以1个月为1个疗程,3个疗程后随访观察患者Harris评分、视觉模拟评分法(VAS)评分以及髋关节活动度。结果:治疗后24个月,2组患者Harris评分、VAS评分、髋关节屈髋范围、外展内收活动度较治疗前均有改善(P<0.05),且治疗组优于对照组(P<0.05)。结论:体外冲击波联合股骨头坏死愈胶囊治疗早期股骨头坏死具有良好的临床疗效,能减轻患者髋关节疼痛,延缓患者后期髋关节置换。

股骨头坏死愈胶囊联合多孔钽棒治疗早期股骨头坏死临床观察

目的:探讨股骨头坏死愈胶囊联合多孔钽棒治疗早期股骨头坏死的临床疗效。方法:将ARCO分期Ⅰ期和Ⅱ期的股骨头坏死患者54例(60髋),按住院号随机分为治疗组27例(29髋)和对照组27例(31髋)。治疗组采用多孔钽棒植入术后口服股骨头坏死愈胶囊治疗,对照组仅采用多孔钽棒植入术治疗。术后对所有患者进行随访观察,评价2组患者的髋关节Harris功能评分、临床疗效及骨修复情况。结果:治疗后,2组患者髋关节Harris功能评分均较治疗前有明显提高,差异有统计学意义(P<0.05);治疗组髋关节Harris功能评分优于对照组,差异有统计学意义(P<0.05)。治疗组优10髋,良15髋,可3髋,差1髋,总有效率为96.55%;对照组优5髋,良10髋,可9髋,差7髋,总有效率为77.42%。2组比较,差异有统计学意义(P<0.05)。治疗组的骨修复情况优于对照组。结论:股骨头坏死愈胶囊联合多孔钽棒治疗早期股骨头坏死,能有效改善患者的患髋功能,缓解关节疼痛,提高患者生活质量,其近期疗效显著。

Treatment of Non-union Femoral Neck Fractures with Vascularized Fibula Grafting

Objective: To investigate the value of transplantation of vascularized fibula in treating non-union femoral neck fractures and preventing ischemic necrosis of the femoral head. Methods : Vascularized heterotopic fibula was transplanted to the anterior-lateral part of the femoral neck. The fibula artery and vein were anastomosised with lateral circumflex artery and vein. Results : One hundred and twenty-nine cases of non-union femoral neck fracture were treated with vascularized fibula graft in our hospital from 1982 to 2002. Eighty-seven cases of them were followed up for 3 to 19 years with functional and X-ray examination. The percentage of fracture healing and effect were 94. 3 and 81. 6, respectively. Conclusion:The fibula with blood supply has a synergistic fixation impact on the non-union femoral neck fractures. The fibula is solid enough for supporting the femoral head and preventing it from collapse. The vascularized fibula grafting, by providing blood supply to the affected femoral head and neck, could promote the femoral head restoration and reconstruction. In addition, the periosteum of fibula plays a role in fracture healing.

Long-term Follow-up Study on Perthes Disease

Objective: To analyze the efficacy of various therapies on Perthes diseaseand summarize a systematic treatment strategy. Methods: One hundred and sixty-five cases merelong-term followed. The advantages and disadvantages of various therapies were compared. Results:Each method had its advantage and disadvantage; the effects were correlated with the stages andtypes of the patients and the therapy they were given. Simple treatment is recommended for type Ⅰcases . For type Ⅱ , simple procedures can be used in stage Ⅰ of the patients and surgery wasusually contraindicated for stage Ⅲ cases . For type Ⅲ, vascularized fibula grafting may beconsidered for cases of stage Ⅰ , Ⅱ and Ⅲ. For type Ⅳ cases, combined therapies should beenconsidered. Conclusion: The therapy should be individualized to patient.

An Experimental Study of Pathogenesis of Steroid-induced Avascular Necrosis of Femoral Head

Objective: To explore the pathogenesis of avascular necrosis of femoral head(ANFH) and search an effective method for clinical practice. Methods: Twenty-four Japanese rabbitswere divided into 2 groups of models and controls. ANFH models were produced byintramuscular-injection of large dosage of steroid to rabbits for 8 weeks. From the 4th, 8th and12th week after production of models, 2 rabbits of each group were sacrificed to observe thestructure of femoral head through light microscope and scanning electron microscope. The contents ofNitric Oxide (NO), tissue-type plasminogen activator (t-PA) and -plasminogen activator inhibitor(PAI) in plasma of the 4 rabbits in each group were estimated at the same time. Results: Comparedwith control group, the rabbits of model group exhibited many differences: such as osteoporosis offemoral head, the presence of more bone lacuna and fat cell through light microscope observing; thebroken and sunk bone trabecula, the loosen and broken collagen fibers on the surface of bone matrixthrough scanning electron microscope observing. Compared with control group, the Concentration ofNO and t-PA in plasma of the model rabbits decreased obviously, but the Concentration of the PAIincreased obviously. Conclusion: The steroid-induced ANFH might be related to the lower level of NOand the descent of fibrinolytic activity.

BASIC FIBROBLAST GROWTH FACTOR GENE TRANSFECTION TO ENHANCE THE REPAIR OF AVASCULAR NECROSIS OFTHE FEMORAL HEAD

Objective To explore a new method for the therapy of avascular necrosis of the femoral head. Method The recombinant plasmid pCD-rbFGF was mixed with collagen and was implanted in the necrotic femoral head. Expression of basic fibroblast growth factor (bFGF) was examined by RT-PCR and immunohistochemical method. Re-pair of the femoral head was observed by histological and histomorphometric analysis. Result Expression of bFGF was detected in the femoral head transfected with bFGF gene, indicating significant increase of angiogenesis 2 weeks after gene transfection and increased new bone formation 8 weeks after gene transfection on histom-orphometric analysis (P< 0.01). Conclusion Transfection of bFGF gene enhances bone tissue angiogenesis. Repair in osteonecrosis would be accelerated accordingly.

The changes of nitric oxide and hemorheology in steroid-induced avas-cular necrosis of femoral head

Objective: To explore the pathogenesis of avascular necrosis of femoral head (ANFH), the early diagnosis index and the treatment effective index of ANFH in clinical practice. Methods: Twenty-four Japanese rabbits were divided into 2 groups: model group and control group. ANFH models were produced by intramuscular injection of large dosage of steroid to rabbits for 8 weeks. On the 4 th, 8 th week after the injection, two rabbits each time from each group were taken to observe the structure of femoral head by light microscope and scanning electron microscope. Four other stomach-empty rabbits from each group were also used to test the contents of Nitric Oxide (NO), contents of the hemorheology indexes. Results: Compared with the control group, the rabbits in the model group exhibited osteoporosis of femoral head and more bone lacuna and more fat cells through light microscope. Through scanning electron microscope observation bone trabecula were broken and sunk, and collagen fibers on the surface of bone matrix became loosen and broken, more osteocyte had pyknosis, adipocyte in the medullary cavity were enlarged and subchondral arterioles and capillaries of the femoral head were pressed by adipocyte. Compared with the control group, the model rabbits contained less NO and obvious increase of the plasma viscosity (PV), low blood viscosity (LBV), erythrocyte hematocrit (HCT), indices of erythrocyte rigidity (TK) and indices of erythrocyte aggregation (AI), plasma fibrin level (PFL) (P<0. 01) and an increase of erythrocyte electrophoresis rate (ERT) (P< 0.05). High blood viscosity (HBV), and erythrocyte sedimentation rate (ESR) were unchanged. Conclusion: The steroid-induced ANFH might be related to less NO and the abnormal hemorheology; and NO and hemorheology should be considered as an early diagnosis index for ANFH in clinical practice.

Effects of Chai-Qin-Cheng-Qi Decoction on cefotaxime in rats with acute necrotizing pancreatitis

AIM:To investigate the effect of Chai-Qin-Cheng-Qi Decoction(CQCQD)on cefotaxime(CTX)concentration in pancreas of rats with acute necrotizing pancreatitis (ANP). METHODS:Sixty healthy male Sprague-Dawley rats were divided randomly into an ANP group(ANP model +CTX,n=20),treatment group(ANP model+CTX +CQCQD,n=20)and control group(normal rats+ CTX,n=20).ANP models were induced by retrograde intraductal injection of 3.5%sodium taurocholate (1 mL/kg),and the control group was injected intraductally with normal saline.All rats were injected introperitoneally with 0.42 g/kg CTX(at 12-h intervals for a continuous 72 h)at 6 h after intraductal injection. Meanwhile,the treatment group received CQCQD (20 mL/kg)intragastrically at 8-h intervals,and the ANP and control group were treated intragastrically with normal saline.At 15 min after the last CTX injection,blood and pancreas samples were collected for the determination of CTX concentration using validated high-performance liquid chromatography. Pathological changes and wet-to-dry-weight(W/D) ratio of pancreatic tissue were examined. RESULTS:Serum CTX concentrations in three groups were not significantly different.Pancreatic CTXconcentration and penetration ratio were lower in ANP group vs control group(4.4±0.6μg/mL vs 18.6± 1.7μg/mL,P=0.000;5%vs 19%,P=0.000),but significantly higher in treatment group vs ANP group (6.4±1.7μg/mL vs 4.4±0.6μg/mL,P=0.020;7% vs 5%,P=0.048).The histological scores and W/D ratio were significantly decreased in treatment group vs ANP and control group. CONCLUSION:CQCQD might have a promotive effect on CTX concentration in pancreatic tissues of rats with ANP.

Can hip abduction reduce the risk of femoral head necrosis deteriorated into osteoarthritis?A 3D finite element analysis

The purpose of this study was to investigate biomechanical behavior changes of femoral head necrosis(FHN)by increasing lower extremity abduction(LEA)angle,offering scientific basis on choosing the LEA procedure for the exact classifications.Methods:Thirty computational models were constructed and used to simulate six different abducent angles with five different progresses of FHN.The initial model was validated by the bony density distribution in X-rays images and the photograph of the cadaver bone in cross-section.The stress transfer path(STP)of each model was analyzed and the contact stresses were assessed.Results:During the midstance phase,STP of type A showed strong similarities with the healthy level;STP distribution was from the top of the femoral head to the calcar;the damage area of STP of type B was approximately 25%of the healthy.While STPs in both type C1 and C2 were broken off.As the increase of the abduction angle,STP of type B transformed into type A,STP of type C1 transformed into type B.STP of type C2 transformed into type C1.There was no significant difference in contact stress between the four settings of FHN and normal femoral head.Conclusions:We found computational biomechanical technique to be a sensitive and useful method for distinguishing the biomechanical difference of FHN during abduction gait.These results showed that LEA motion could effectively reduce collapse risk and interrupt the disease pathway of FHN deteriorated into osteoarthritis.Furthermore,our findings indicated that the LEA procedure was suitable for type A,B and C1,while type C2 of FHN involved surgical intervention might get a better clinical outcome.

Research progress of microRNA in prevention and treatment of osteonecrosis of the femoral head

In the 1980s,Feinbaum et al.first discovered miRNA in the development of worms and termed it as Lin-4.With the development of microbial science and continuous improvement in the gene sequencing technology,miRNA has been gradually gaining attention for intensive research in clinical medicine.Among these,one group of miRNAs has been confirmed to play fundamental roles in gene regulation in various orthopedics diseases,such as bone tumors,osteoarthritis,and rheumatoid arthritis.The study of miRNAs in the osteonecrosis of the femoral head(ONFH)can improve the understanding of the pathogenesis of the disease.ONFH is an orthopedic disease that is the primary cause of disrupted blood supply to the femoral head and the main symptoms of bone and muscle dysfunction.Recent studies showed that miRNA played a major role in the regulation of the microcirculation of ONFH,damage and repair of blood vessels,local microcirculation dysfunction caused by other diseases,and apoptosis of bone cells.In this study,recent related research results of miRNA and ONFH were analyzed and summarized,and the prospective in the prevention and treatment of the disease was also discussed.

Changes of bone mineral in steroid-induced osteonecrosis in rabbits

To investigate the significance of bone mineral changes in the pathogenic process of steroid-induced osteonecrosis in rabbits. Methods： Seventy adult female Japanese White rabbits were randomly divided into five groups Animals in steroid group received an intramuscular injection of methylprednisolone acetate （4 mg/kg） once a week, and killed in four different time after first treatment. Animals in control group received an intramuscular injection with the same volume of normal saline, while 150 kU penicillin was injected twice a week for preventing infection in all groups. The contents of serum calcium （Ca） and phosphorus （P） were determined and the bone mineral densities of the femoral head and neck were measured at the 2nd, 4th, 8th and 10th weeks after first treatment. Meanwhile the general condition such as weight, spirit and hair of rabbits was observed. Results： Compared with the control group, the weight of rabbits in steroid group lost since the first week, and progressively aggravated; the bone mineral density of the femoral head and neck was lowered since the 2nd and 4th week respectively （P〈0.05, P〈0.01）, and lowered more quickly in femoral neck than in femoral head. In steroid group, the bone mineral density of the femoral neck at the 10th week was significantly lower than that at the 8th week （P〈0.05） Compared with the control group, the serum levels of Ca and P in steroid group were lowered since the 2nd week （P〈0.05, P〈0.01）. In steroid group, the serum Ca level at the 10th week was lower than that at the 8th week, and the serum P level waslowered more quickly than Ca level was. Conclusion： Osteonecrosis appears in rabbits shortly after corticoids are first administered, and osteonecrosis in rabbits is chronologically associated with the onset of hypocalcaemia, hypophosphatemia and lowered bone mineral density. Steroid-induced osteonecrosis may be relevant to bone mineral loss and density lowering of the femoral head and neck.

A 3-D DDA damage analysis of brick masonry buildings under the impact of boulders in mountainous areas

In mountainous areas, geological disasters carrying large boulders can cause severe damage to the widely used masonry buildings due to the high impact forces. To better understand the damage of brick masonry buildings under the impact of boulders, a "block-joint" model is developed using threedimensional discontinuous deformation analysis(3-D DDA) to simulate the behaviour of the "brick-mortar" structure. The "block-joint" model is used to capture not only the large displacement and deformation of individual bricks but also the large-scale sliding and opening along the mortar between the bricks. The linear elastic constitutive model is applied to account for the non-plastic deformation behaviour of brick materials. Furthermore, the mechanical characteristics of the mortar are represented using the Mohr-Coulomb and Drucker-Prager criteria. To propose safe structural design schemes and effective reinforcement for brick masonry buildings, seven construction techniques are considered, includingdifferent grades of brick and mortar, effective shear areas and reinforced members. The proposed 3-D DDA model is used to analyse the velocity distribution and the key point displacements of the brick masonry building under the impact of boulders. The results show that upgrading the brick and mortar, increasing the wall thickness, making full use of the wall thickness, and adding a circular beam and structural column are very effective approaches for improving the impact resistance of brick masonry buildings.

Using Thermoelastic Stress Analysis to Detect Damaged and Hot Spot Areas in Structural Components

This paper discusses the suitability of using TSA （thermoelastic stress analysis） as an advanced tool to detect damaged areas and highly stressed （hot spot） areas in structural components. Such components can be, for example, parts of large structural panels built of welded metallic or composite materials. Besides detecting hot spot areas, it is expected that stresses in these areas can be suitably quantified and processed in order to predict crack initiation and propagation due to in-service loads. The paper starts with references to selected review and application articles on the subject. Two simple laboratory experiments are presented which illustrate the quality of the results that can be achieved using TSA. In the first experiment, a stainless steel T-joint designed to model a welded structural component is analysed. The T-joint had a machine-notched crack-like flaw close to the component＇s weld toe. The qualitative and quantitative experimental results determined along four specified areas of the T-joint model showed that TSA can indeed be used as a tool to detect loaded cracks and hot spots in large metallic structures, and that stresses can be accurately evaluated. In the second experiment, a prismatic bar made of CFRE （carbon fibre-reinforced-epoxy） was tested to locate three subsurface areas of damage introduced beforehand into the component. Two of these inside damaged areas were detected to be 3.1 mm and 7.1 mm from the observed surface. The positive results achieved with the two lab experiments, along with a review of the selected research publications, indicate that TSA application can be extended to the real-world field of structural components. Topics to be addressed in this research field should have to do with components that work under random or quasi-cyclic service loading, problems where adiabatic conditions do not prevail, and reduction of the cost of infra-red cameras.

HISTOMORPHOMETRIC STUDY OF SUBCHONDRAL BONE OF NECROTIC FEMORAL HEAD IN RABBITS INDUCED BY METHYLPREDNISOLONE COMBINED WITH LOW-DOSE LIPOPOLYSACCHARIDE

Objective To investigate the histomorphometric features of the necrotic femoral head of rabbits induced by methylprednisolone combined with lipopolysaccharide. Methods Thirty-two mole adult New Zealand white rabbits were used. Among them, 16 were injected with lipopolysaccharide and methylprednisolone （ osteonecrosis group） , and another 16 were sham-injected with saline （ control group）. Magnetic resonance （MR） imaging was taken for femoral heads of the rabbits in both groups at the end of 2, 4 and 6 weeks after the injection. All the rabbits were then killed 6 weeks later. The femoral heads of the rabbits were collected and processed for histological and histomorphometric analysis. Results Femoral head necrosis occurred in 14 rabbits of the osteonecrosis group which were confirmed by histological evaluation and MR imaging. Osteonecrotic femoral heads, compared to controls, were characterized by lower values of bone volume/tissue volume （ P 〈 0. 01 ）, tabecular thichness （ P 〈 0. 01 ） , osteoid surface/bone surface （ P 〈 0. 05 ）, mineralizing apposition rate （ P 〈 0 05 ）, and bone formation rate/bone surface （ P 〈0. 05 ）. However, tabecular separation and eroded surface/bone surface were higher in osteonecrotic femoral heads than in controls （ P 〈 0. 01 ）. Trabecular number and osteoclast surface/ bone surface did not differ significantly. Conclusion The results demonstrated that osteoporosis was apparent in osteonecrotic femoral heads induced by methylprednisolone and lipopolysaccharide, due mainly to trabecular thinning rather than reduction of trabecular number. This might be due to reduced bone formation combined with increased bone resorption.

Total hip arthroplasty for treatment of elderly patients with comminuted intertrochanteric fracture accompanied by femoral head necrosis

Objective： To assess the curative effect and investigate the indications of total hip arthroplasty for treatment of comminuted intertrochanteric fractures. Methods： Total hip arthroplasty was carried out in 9 cases of severe intertrochanteric fracture. The patients included two men and seven women. The average age of the patients was 68 years （48-75 years）. The period from fracture to operation was 5 days （2-10 days）. The mean follow- up period lasted for 11 months （3 months-2 years）. There was one patient with comminuted intertrochanteric fracture accompanied by femoral head necrosis and 2 patients with intertrochanteric fracture and stroke. Other 6 patients had severe osteoporosis. The Harris score before operation was 63 points （45-71 points）.Results： At the last follow-up, the patients gained 86points （70-100 points） according to the Harris score. The effects of the 8 cases were good. The Harris score of all patients improved after treatment. Only two hemiplegia patients needed sticks to walk. The others could walk without hip pain. No radiographic evidence of acetabular wear and prosthesis dislocation or other major complications happened during the follow-up. Conclusions： Prosthetic replacements can well treat unstable intertrochanteric fracture if operative indication is correctly selected. It is suitable for elderly patients and the operation should be performed by experienced surgeons.

Effect of dynamic hip system blade on the treatment of femoral neck fractures in elderly patients with osteoporosis

Objective：To discuss the curative effect of the dynamic hip system blade （DHS-blade） on the treatment of femoral neck fractures in elderly patients with osteoporosis.Methods：A retrospective study was conducted to analyse the clinical data of 60 elderly patients with osteoporosis who had been treated for femoral neck fractures with DHS-blade in our department between September 2012 and February 2014.There were 22 males and 38 females with a mean age of （66.8±3.2） years.According to the Singh Index Classification,all the patients＇ Singh index was below level 3.The Harris criterion and function recovery after operation were analysed.Results：All patients were followed up for 12-17 months （mean 14 months）.No femoral head necrosis,femoral neck shortening,internal fixation loosening or backing out of the nails occurred.Bone nonunion was found in one case and he had a good recovery after total hip arthroplasty.The time for fracture healing ranged from 3-6 months （average 3.5 months）.According to Harris criterion,35 cases were rated as excellent,22 good,2 fair and 1 poor.The Harris scale was significantly improved from 28.46±2.35 preoperatively to 91.98±3.26 at 6 months postoperatively （P＜0.05）.Conclusion：DHS-blade,being minimally invasive,allowing earlier postoperative exercise and avoiding the complications elicited by traditional internal fixation,is advisable for treatment of femoral neck fractured patients with osteoporosis.

Treatment of osteonecrosis of femoral head with BMSCsseeded bio-derived bone materials combined with rhBMP-2 in rabbits

Objective： To evaluate the effect of autologous bone marrow mesenchymal stem cells （BMSCs） seeded bio-derived bone materials （BBM） combined with recombinant human bone morphogenetic protein-2 （rhBMP-2） in repairing defect of osteonecrosis of femoral head （ONFH）. Methods： Early-stage osteonecrosis in the left hip was induced in 36 adult New Zealand white rabbits （provided by the Animal Center of Guangxi Medical University, Nanning, China） after core decompression and delivery of liquid nitrogen into the femoral head. Then the animals were divided into three groups according to the type of implants for bone repair： 12 rabbits with nothing （Group Ⅰ, the blank control group）, 12 with BBM combined with rhBMP-2 （Group Ⅱ）, and 12 with BMSCs-seeded BBM combined with rhBMP-2 （Group Ⅲ）. At 4, 8, and 12 weeks after surgery, X-ray of the femoral head of every 4 rabbits in each group was taken, and then they were killed and the femoral heads were collected at each time point, respectively. Gross observation was made on the femoral heads. After hematoxylin and eosin staining, Lane-sandhu scores of X-ray and bone densitometry were calculated and the histomorphometric measurements were made for the new bone trabeculae. Results： At 12 weeks after surgery, two femoral heads collapsed in Group Ⅰ, but none in Group Ⅱ or Group Ⅲ. X-ray examination showed that the femoral heads in Group I had defect shadow or collapsed while those in Group II had a low density and those in Group III presented with a normal density. Histologically, the defects of femoral heads were primarily filled with no new bone but fibrous tissues in Group Ⅰ. In contrast, new bone regeneration and fibrous tissues occurred in Group II and only new bone regeneration occurrd in Group Ⅲ. Lane-sandhu scores of X-ray, bone mineral density and rate of new bone in trabecular area in Group Ⅲ were higher significantly than those of the other two groups. Conclusions： Our findings indicate a superior choice of repairing the experimental defect of OFH with BMSCsseeded BBM combined with rhBMP-2.

Outcome of bone marrow instillation at fracture site in intracapsular fracture of femoral neck treated by head preserving surgery

Purpose： The aim of present study is to evaluate the outcome of bone marrow instillation at the fracture site in fracture of intracapsular neck femur treated by head preserving surgery. Methods： This study included 32 patients of age group 18e50 years with closed fracture of intracapsular neck femur. Patients were randomized into two groups as per the plan generated via www.randomization.com. The two groups were Group A （control）, in which the fracture of intracapsular neck femur was treated by closed reduction and cannulated cancellous screw fixation, and Group B （intervention）, in which additional percutaneous autologous bone marrow aspirate instillation at fracture site was done along with cannulated cancellous screw fixation. Postoperatively the union at fracture site and avascular necrosis of the femoral head were assessed on serial plain radiographs at final follow-up. Functional outcome was evaluated by Harris hip score. Results： The average follow-up was 19.6 months. Twelve patients in each group had union and 4 patients had signs of nonunion. One patient from each group had avascular necrosis of the femoral head. The average Harris hip score at final follow-up in Group A was 80.50 and in Group B was 75.73, which was found to be not significant. Conclusion： There is no significant role of adding on bone marrow aspirate instillation at the fracture site in cases of fresh fracture of intracapsular neck femur treated by head preserving surgery in terms of accelerating the bone healing and reducing the incidence of femoral head necrosis.

HuoguⅠformula prevents steroid-induced osteonecrosis in rats by down-regulating PPARγ expression and activating Wnt/LRP5/β-catenin signaling

OBJECTIVE： To investigate the effects of Huogu I formula on regulation of lipid metabolism in ste- roid-induced osteonecrosis of the femoral head （SONFH） rats and verify our hypothesis that Huogu I formula regulates lipid metabolism by down-regulating peroxisome proliferator-activated receptor gamma （PPARy） expression and activating Wnt signaling pathways. METHODS： Eighty-five rats were divided into four groups： control, model, Huogu 15 g/kg and Huogu 30 g/kg. Six weeks later, animals were anaesthe- tized, femora were dissected for histopathologicalexamination of the osteonecrotic changes and re- pair processes, micro computed tomography （Mi- cro-CT）-based micro-angiography was performed to assess vascularization. Serum lipid levels were detected by haematological examination. The ex- pressions of PPARy, Wnt3a, low density lipoprotein receptor-related protein 5 （LRP5） and 13-catenin were evaluated by immunohistochemistry, Western blot and quantitative real-time polymerase chain reaction analyses. RESULTS： The incidence of osteonecrosis, ratio of empty lacuna, adipose tissue area and adipocyte perimeter in the bone marrow were dramatically lower in the Huogu ~ formula treatment groups. By micro-CT quantification, Huogu ~ formula treat- ment dose-dependently increased vessel volume, vessel surface, percentage of vessel volume and vessel thickness of the femoral heads of SONFH rats. Levels of serum lipid in Huogu 15 g/kg and Huogu 30 g/kg groups reduced significantly. HuoguⅠformula treatment could suppress the ex- pression of PPARy and increase the expressions of Wnt3a, LRP5 and 13-catenin at both protein and mRNA levels. CONCLUSION： The results of our present study highlight the lipid-lowering potential of Huogu Ⅰ formula, and provide further evidence of the in- volvement of the PPARy inhibition and Wnt/LRPS/ 13-catenin signaling activation in the effects of Huogu Ⅰ formula.