Titanium Alloy Cage Implantation for the Treatment of Ischemic Necrosis of Femoral Head in Dogs

To study the effect of titanium alloy cage on the treatment of the ischemic necrosis of femoral head in dog, the model of the ischemic necrosis of femoral head was made with the liquid nitrogen in 15 hybrid adult dogs. The titanium alloy cage made of a hollow cylinder was driven into the subchondral bone of necrotic femoral head via central channel. The dogs were divided into 3 groups, each group was sacrificed 3, 6, 12 weeks after the operation respectively. No collapse of femoral head was observed after the operation. The position of the cages was good on radiograph. Microscopically, the cancellous bone of necrotic femoral head rebuilt gradually and grew into cage. After 12 weeks of creeping substitution, the cancellous bone filled up the hollow cavity and holes of the cages. It is concluded that the titanium alloy cage can provide structural support for the subchondral bone and prevent collapse and can be used for the treatment of the ischemic necrosis of femoral head.

Experimental study of changes of TNF-α in rabbits with steroid-induced avascular necrosis of femoral head

Objective: To explore the effect of tumor necrosis factor-α(TNF-α)on the occurrence of steroid-induced avascular necrosis of femoral head(SANFH). Methods: Twenty-four rabbits were firstly divided into void group (n=12) and model group (n=12) at random. Prednisone Acetate was injected to the model group(0.32 mg·kg^(-1)·d^(-1)). In the 6 th and 8 th week, two rabbits of the two groups were killed respectively to observe whether the model was successful. The level of TNF-α in serum of the residual rabbits of the two groups was examined in Radioimmunoassay method. Results: The level of TNF-α in model group is significantly higher than that in void group(P<0.001) under the premise of the model of SANFH success by histological observation. Conclusion: The rise of level of TNF-α may be one of the most important factors in the occurrence of SANFH.

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.

Efficacy and safety evaluation of intravenous infusion of cervus and cucumis polypeptides for treatment of avascular necrosis of the femoral head: a randomized clinical trial

OBJECTIVE: To investigate the efficacy and safety of intravenous cervus and cucumis polypeptides for treating avascular necrosis of the femoral head(ANFH) in regard to pain and hip function in a randomized clinical trial.METHODS: A total of 96 subjects with ANFH who were recruited at the Orthopaedic Hospital Affiliated with Hebei United University and Qian Hai Femoral Head Hospital of Beijing were assigned by lottery to an intervention group(n = 48) or a control group(n = 48). All subjects underwent physical therapy and rehabilitation exercises. In addition,subjects in the intervention group were given intravenous infusions of cervus and cucumis polypeptides. Visual analogue scale(VAS), Harris hip score,and radiography or magnetic resonance imaging were applied to assess all subjects at the beginning of treatment and 3, 6, and 9 months afterward. All the subjects were followed up for 2 years.RESULTS: At the beginning of treatment, there were no statistically significant differences between the two groups in terms of the general condition of patients or the VAS and Harris hip scores(all P > 0.05). At 3, 6, and 9 months after treatment,however, the VAS score decreased and the Harris hip score increased in all patients, with the improvement of intervention group significantly greater than that of the control group(P < 0.05).The total effectiveness rates for the intervention and control groups were 89.58% and 70.83%, respectively, with the difference being statistically significant(P < 0.05). There was no statistically significant difference between the two groups in terms of the safety of the injections(P > 0.05).CONCLUSION: Intravenous infusion of cervus and cucumis polypeptides relieved pain and improved hip function of subjects with ANFH.Thus, the intravenous infusion of cervus and cucumis polypeptides was a safe, effective treatment for ANFH.

Prediction of traumatic avascular necrosis of the femoral head by single photon emission computerized tomography and computerized tomography： an experimental study in dogs

Objective： To evaluate the femoral head perfusion and to predict the traumatic avascular necrosis （AVN） of the femoral head by single photon emission computerized tomography and computerized tomography （SPECT/CT）. Methods： Totally 18 adult beagle dogs were divided randomly into three equal-sized （n=6） groups. Subsequently different degrees of ischemia model were developed by de- stroying blood vessels of the femoral head. The left hip received sham operation as normal control and the right hip underwent blood interruption. In Group A, the ligamentum teres was cut off. In Group B, the marrow cavity of the right femoral neck was destroyed while in Group C, the soft tis- sues at the base of the femoral neck were stripped in addition to the resection of the ligamentum teres and destruction of the marrow cavity. Three hours after surgery, SPECT/ CT was performed. Laser Doppler Flowmetry （LDF） measurements were also obtained at three different time points （before operation, immediately and three hours after operation） in order to assess the change process of blood supply to the femoral head. Results： SPECT/CT showed no significant difference in the radionuclide uptake between the right and left femo- ral heads in Group A （t=-0.09,P=-0.94） and Group B （t= 0.52, P=0.62）. However, in Group C, it was 261±62 for the right femoral head, only 12% of that in the left femoral head. LDF measurements indicated that the femoral head perfusion was decreased from （45.0±3.3） PU to （39.1±3.7） PU in Group A, from （44.0±2.7） PU to （34.3±2.6） PU in Group B, and from （47.3±2.1） PU to （4.96±0.6） PU in Group C immediately after operation. However, the perfusion was restored and returned to normal values three hours after operation except in Group C. Conclusion： SPECT/CT could assess the perfusion of the femoral head semiquantitatively, which might be useful in predicting the development of traumatic AVN.

Spontaneous fracture of the femoral neck in preexisting avascular necrosis of femoral head in sickle cell dis-

Avascular necrosis of the femoral head is a known complication of femoral neck fracture but on the contrary, femoral neck fracture in a case of preexisting avascular necrosis is a very rare phenomenon. We present a case study of a 47 year old Iraqi male who developed sponaneous ipsilateral subcapital femoral neck fracture under the condition of preexisting sickle cell disease and avascular necrosis of the femoral head. The fracture was unnoticed for a few months. The patient was managed successfully byuncemented total hip arthroplasty. Postoperative recovery was uneventful and he was discharged 4 days after surgery. At 1 year＇s follow-up, the patient had normal gait and hip function, with no sign of loosening or any other complications on radiograph.

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.

Clinical study on the related markers of blood coagulation in the patients with ANFH after SARS

The aim of this research was to investigate the blood coagulation function in the patients with avascular necrosis of the femoral head(ANFH)after severe acute respiratory syndrome(SARS).The expression of CD31,CD61,CD62p,CD63 and PAC-1 on platelet membrane was measured respectively by flowcytometry,and the plasma prothrombin time(PT),activated partial thromboplastin time(APTT),thrombin time(TT)and fibrinogen(Fbg)were mea-sured by blood clotting instrument in 26 patients with ANFH after SARS and in 17 healthy adults.The expression of CD31,CD61,CD 62p,CD63 and PAC-1 on platelet membrane in 26 patients was all lower than that in 17 healthy subjects(P<0.01).The levels of PT,APTT,TT and Fbg in 26 patients were all normal.There is no significant difference(P>0.05)in those markers between patients and 17 healthy adults.The blood may not be in hypercoagulable state in patients with ANFH after SARS.

Horizontal platform supported total hip replacement

Objective To investigate the effect of horizontal platform supported (HPS) prosthesis on cementless total hip replacement for surgical treatment of arthritis in a long-term follow-up study.Methods Clinical and radiographic follow-up of 65 consecutive primary cementless porous coated HPS total hip replacements, which were implanted in 60 patients between 1982 and 1989, was carried out.Results The 53 hips in 50 patients were evaluated both clinically and radiographically. The average follow-up was 6.8 years (range: 5 to 12 years). According to the Harris hip score, 52 (98%) of the hips had sustained an excellent or good result with an average score of 92. At the time of final assessment, no patient experienced anterior thigh pain. There were two revisions performed early in the series due to technical failures. Radiographically, osteolysis and bone re-modelling were assessed. Conclusion The findings suggest that the clinical and radiographic results after cementless total hip replacement for primary hip arthroplasty may be favourably influenced by the use of the proximal stress loaded HPS femoral component.