Objective To report the experience of the revision procedure with morselized bone grafting and a special design of acetabular prosthesis with three wings for loosened acetabular component in our hospital. Methods Since December 1989 to Junanry 1999, 23 cases with loosened acetabular component and bone defect were revised by morselized bone auto/allografting. There were 12 males and 11 females, the average age of the patients was 54.2 years old (range from 38 to 71 years old). The prosthesis of primary THA was double cup in 4 cases, the conventional THA in 19 cases, cemented in 22 cases and cementless in 1 cases. The severity of acetabular component loosening was classified into four types according to Gustillo: Type II in 3 cases, type III in 9 cases and type IV in 11 cases. The morselized bone autografting and allografting with size 4－ 6 mm were used in 6 cases and in 17 cases respectively. Different acetabular components had been used, the thread metal acetabular cup in 2 cases, screw fixed conventional metal acetabular cup in 10 cases and special design acetabular prosthesis with three wings in 11 cases. The latter prosthesis consists of an conventional acetabular component with pearl porous surface and three wings with different length and sharp edge distributed centrally in the superior lateral quadrant on the surface, the liner is made of UHMPE. Results No infection of the wound occurred in this group. The mean time of follow- up was 3 years and 8 months. Except 3 cases, all of the bone grafts was healed well and X－ ray showed that the containing of acetabular component was good, no translucent line between donor bone bed and prosthesis, and the bone defect had been repaired. The average Harris score was 47 before revision, and 86 after revision. The successful rate of revision was 86.9％ . There were 3 loosening cases postoperatively, 2 cases were due to incorrect position of prostheses and insufficient bone graft, another case was due to the screw being too short to fix the acetabular component. However, all of the three cases have partial bone growth in the original loosening acetabular. Conclusion 1. Direct contact between the morselized bone auto/allograft and the surface of metal acetabular component and the firm fixation of the prosthesis have showed good result of bone defect reconstruction. 2. The special design of acetabular prosthesis with three wings could be selected as an alternative method for huge bone loss of acetabulum (ranged from 64 to 79 mm), because it was able to enlarge the volume of the acetabular component.

Objective Experimental and clinical data suggest that fixed element knee designs a re not able to both supply adequate mobility and eliminate unnecessary constra int forces,as well as provide low contact stresses compatible with pr olonged life of UHMWPE bearing components.The present study investi-gated the preliminary clinical outc ome of TACK(Total Articulating Cementless Knee)system,a new design of mobile-bearing knee prosthesis.Methods Eighty-eight knees in 61patients underwent total knee replace-ment by using TACK were reviewed.Forty-five knees of 31patients were followed-up at least one year.The HSS knee rating score system as well a s X-ray films were used to evaluate th e clinical results with the mean follow-up period of 25.4months.Results At the latest follow-up examination,the rate of good to excellent clinical results was 96.4%.The range of motion was improved from 0-6.5-68.3degrees preoperatively to0-2-88.4degrees at the latest follo w-up.The complications such as oste olysis around the prosthesis,prosthetic loosening and dislocation of meniscus bearings were not found.Conclusion The TACK Knee is a third generation knee system design ed to introduce movable bearings between the metal tibial and femoral components that would reduce the sur face and subsurface stress states at the bearing surfaces and at the bone-implant interfaces by maximiz ing the conformity of the tibial and f emoral components and allowing mo-bility of the bearing surface.In an a verage of more than two years experie nce,it was observed that there was no aseptic loosening of the componen ts.A long term follow-up is obviously necessary to make more precise statement about this knee replaceme nt system.

Objective In order to explore the possibility of bone ingrowth into a hollow prosthesis at the bone-implant interface, and the promoting effects induced by rhBMP-2/carrier compound as well. Methods Bone harvest chamber (BHC) modified form Albrektsson designation, was implanted into meta-physis of tibia of New Zealand rabbit to establish an animal model. 10 ?l rhBMP-2 and rhBMP-2/Healon GV compound, each of which contained 1mg rhBMP-2, were loaded into BHC respectively. The same vol-ume of Healon GV and injection water was also loaded into as control. The tissues in the BHC were harvest- ed at 2, 4 and 6 weeks after implantation respectively. Histological observation with non-decalcified slicing technique was adopted, and bone histomorphometry was analyzed by computerized image analysis system to calculate TBV (trabecular bone volume). The data was compared among the different groups. Results At two weeks after loading, there were woven bone formation in groups of rhBMP-2/Healon GV compound and rhBMP-2, and mature bone trabeculae with marrow-like tissue were observed at 4 weeks; At 6 weeks, new bone formation in the BHC became more intensive. However, the tissues in BHC of Healon GV and injection water at 4 weeks were just like those of the former two groups at 2 weeks, and mature bone trabeculae with marrow-like tissue could only been found until 6 weeks. Conclusion Bone at the interface can grow into the contained space of hollow prosthesis through holes at the wall, and form mature bone. rhBMP-2 loaded in the hollow space can obviously promote this effect and the carrier Healon GV has no negative influence but can increase bone inductive effect.

Objective To compare the results of one-stage bilateral total hip arthroplasty (THA) and staged bilateral THA, and to determine the safety and efficacy of one-stage simultaneous bilateral THA. Methods The patients who were indicated for with bilateral THA were divided into 2 groups. Gourp A included 87 patients with one-stage simultaneous bilateral THA, and Group B included 31 patients with staged bilateral THA. The operating time, the amount of blood loss, the amount of blood transfusion necessary, post-operation functional scores, and perioperative complications were compared between group A and group B. Result There was no significant difference between group A and group B. Conclusion One-stage simultaneous bilateral total hip arthroplasty was a safe and efficacious procedure.

OBJECTIVEThis study aims to do the following: construct a three-dimensional finite element model of an labial inverted impacted maxillary central incisor and its supporting tissues, analyze stress distribution in the periodontal tissue when various tractions are exerted, and provide references for treating impacted maxillary central incisor.

METHODSA three-dimensional finite element model oflabial inverted impacted maxillary central incisor and its periodontal tissues was established using Mimics 10.01 and Ansys 14.0 software based on original cone beam computed tomography (CBCT) data. Various traction values (20, 30, 40, 50, 60, and 70 g) were exerted on the incisal margin in the direction perpendicular to the impacted tooth. Different Von Mises stress values were determined.

RESULTSStress distribution on the periodontal ligament increased with traction size. When 30 g traction was exerted on the labial inverted impacted maxillary central incisor, the Von Mises stress was 24 919.0 Pa, which was within the range of the optimum force and close to its maximum value.

CONCLUSIONThe optimum traction for early orthodontic treatment of labial inverted impacted maxillary central incisor is nearly 30 g.

OBJECTIVE To evaluate the diagnostic values of biochemical tests for infection before revision hip arthroplasty. METHODS One hundred and forty five cases with revision hip arthroplasty were reviewed.The diagnostic results of infected hip arthroplasty according to ESR,CRP and "gold standard" were compared. RESULTS ESR served as the diagnostic criterion of infected hip arthroplasty,its sensitivity,specificity,positive and negative predictive value,accuracy and Youden′s index were 57.89%,85.71%,37.93%,93.10%,20.00 and 0.44,respectively.CRP as the diagnostic criterion of infected hip arthroplasty,its sensitivity,specificity,positive and negative predictive value,accuracy and Youden′s index were 68.42%,88.89%,48.15%,94.92%,18.62 and 0.57,respectively. CONCLUSIONS Being routine tests before revision hip arthroplasty,ESR and CRP play a screening role in the diagnosis of infected hip arthroplasty and compliment each other so that the accuracy of diagnosis can be improved.

BACKGROUND: Carbonated hydroxyapatite cement (CHC) s a new kind of biomaterial for bone defect, which is made of powder and fluid, and can be mixed to be pasty to repair various bone defects.OBJECTIVE: To observe the improvement of vertebrae height and pain in patients with osteoporosis vertebral compression fracture (VCF) after vertebroplasty by using a new kind of bone graft biomaterial, taking CHC as the filling material to reinforce the vertebral body.DESIGN: A contrast observation trial taking patients as subjects.SETTING: Department of Orthopaedics, General Hospital of Chinese PLA.PARTICIPANTS: Totally 34 patients with thoracic or lumbar osteoporosis VCF who received the treatment in the Department of Orthopaedics, General Hospital of Chinese PLA between October 2000 and August 2003. Inclusive criteria: ①Definite diagnosis by CT; ② Informed consents were obtained from the patients. Exclusive criteria: The patients with osteoporosis vertebral compression fractures who suffered vertebral posterior wall fracture. There were 6 males and 28 females, and they were aged (72±13)years; Among the patients, 27 were diagnosed as postmenopausal osteoporosis, 1 as cortical hormone-induced osteoporosis and 6 male patients weresenile osteoporosis.METHODS: ①All the patients were randomly divided into two groups: Experimental group (n =23) and control group (n=11). All the patients were performed percutaneous operation with local anesthenia. All cases were performed percutaneous operation under local anesthesia. Under the C-arm monitored, one side pedicle puncture was performed to enter the anterior column of the involved VCF. Patients of the experimental group were filled with CHC. Patients of control group were filled with polymethyl Methacrylate (PMMA) with the same way. ② Referred to McGill-Melzack scoring. Among the scale 0-100 mm (0 was no pain, 100 was acute pain), the value indicated the painful intensity and mental assault degree. ＜ 30 scores indicated good, 30-40 basically satisfied and ≥ 50 poor .③ Referred to the method from Lee et al, the preoperative height (A1) and postoperative height (A2) of compression fracture position of VCF were measured according to the lateral X-ray film. At the same time, the upper vertebral height (A3) and the inferior vertebral height (A4) were measured at the same position. The original height (A) of the involved vertebra was calculated as (A)= (A3+A4)/2,and the preoperative vertebral compression rate =(A-A1 )/A, the postoperative vertebral compression rate =(A-A2)/A, the restoring rate = (the preoperative vertebral compression rate-the postoperative vertebral compression rate)/the preoperative vertebral compression rate. ④ The wounds of the patients were observed after operation. The levels of blood routine, serum calcium and serum phosphorus were detected before, one day and one week after operation. MAIN OUTCOME MEASURES: ① Preoperative and postoperative VAS scoring. ② The vertebral compression rate and restoring rate. ③ Wounds were observed after operation. The blood routine, the serum calcium and serum phosphorus were detected before, one day and one week after operation.RESULTS: Totally 34 patients were involved in the result analysis. ①The preoperative visual analogue scale (VAS) score of experimental group were (91.5±21.7) points, and the postoperative ones were (44.5±27.2) points. The difference of VAS score reduced gradually along with the postoperative time. There was no difference of VAS score between experimental group and the control group 4 weeks after operation. ② The biocompatibility of CHC in the vertebral body was fine. The vertebral compression rate of experimental group was recovered from (43.1±21.4)％ preoperatively to (27.3± 18.5)％ postoperatively. The rate of restored heights was (27.3±18.5)％. ③ All patients obtained Ⅰ stage wound healing, and none of them had infection, inflammatory secretion and nervous symptom. There were no differences in blood routine test, serum calcium, serum phosphorus between patients in two groups. One case filled by PMMA and two cases filled by CHC presented leakage, and none had nervous symptom.CONCLUSION: As the filling materials for vertebropalsty, CHC can restore the vertebral heights and relieve pain safely and effectively, however, its efficacy to relieve pain is not significant as PMMA in the short term.

BACKGROUND: Carbonated hydroxyapatite cement is a new type material for skeletal repair and hydroxyapatites have been applied in the clinical treatment of skeletal defect.OBJECTIVE: To observe the effective characteristics of carbonated hydroxyapatite cement on repair of skeletal defect by animal experiment.DESIGN: Paired design, self-controlled and verified experiment was applied in the research.SETTING: Orthopedic Institute and Animal Experimental Center of Chinese PLA.MATERIALS: The experiment was performed in Orthopedic Institute and Animal Experimental Center of Chinese PLA from May 2002 to January 2003, in which, 10 healthy adult male mongrel dogs were applied, body mass weighted varied from 20 to 22 kg.METHODS: Animal model of skeletal defect was prepared on proximal ends of humeri of 10 mongrel dogs thydroxyapatitet were randomized into experimental side and control side. Ceramics repair of skeletal defect was done by carbonated hydroxyapatite cement and high-temperature sintered hydroxyapatite respectively. The animals were sacrificed on the 5th day, 4th, 8th, 12th and 16th weeks successively after operation. The repair effects were performed with X-ray and histological observation.staining.Results of stereomicroscopic and X-ray observations on bilateral skeletal defect: Osseointegration with carbonated hydroxyapatite cement was tight on the experimental side and the interface became unclear gradually with time lasting. The interface between hydroxyapatite and bone was still clear on the and eosin staining and thydroxyapatitet of ground bone with Gimsa staining:On the 8th week on the experimental side, the new bone grew into carbonated hydroxyapatite cement, on the 16th week, the two parts were intermixed and integrated and the bone island was formed around newly generated vessels in carbonated hydroxyapatite cement. On the control side, hydroxyapatite still maintained integrated and the bone interface was clear between hydroxyapatite and bone. On the 16th week, the aggradation of newly generated bone presented on hydroxyapatite surface.CONCLUSION: Carbonated hydroxyapatite cement possesses solidification property in situ, biocompatibility and osseous conductive activity. It is the satisfactory new type material for repair of skeletal defect.

BACKGROUND: Primary studies suggest that coronary artery stenosis is highly exactly shown by 16-slice spiral CT coronary artery imaging.OBJECTIVE: To compare the accuracy and limitation between coronary angiography and multi-slice computed tomography (MSCT) coronary artery imaging to diagnose moderate and severe coronary artery stenosis. DESIGN, TIME AND SETTING: Clinical diagnostic study based on gold standard, which was carried out in the Department of Cardiology, Xuanwu Hospital, Capital Medical University from June 2005 to March 2006. PARTICIPANTS: Twenty-eight patients with suspected coronary arteriosclerotic heart disease were examined by 64-slice spiral CT coronary artery imaging and coronary artery angiography during the 1-month hospitalization in the Department of Cardiology, Xuanwu Hospital, Capital Medical University from June 2005 to March 2006. METHODS: 280 segments of 28 patients were quantitatively analyzed coronary artery stenosis by selective coronary artery angiography and multi-slice spiral CT imaging based on eye-measurement diameter method. MAIN OUTCOME MEASURES: True positive, true negative, false positive, false negative, sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of coronary artery stenosis were measured by multi-slice spiral CT imaging.RESULTS: All 28 patients were included in the final analysis. Multi-slice spiral CT imaging showed that the sensitivity, specificity, positive predictive value, and negative predictive value were 46.5%, 97.6%, 86.8%, and 84.3%, respectively. If excluding the effect of 31 coronary segments with severe calcification, the sensitivity, specificity, positive predictive value and negative predictive value were 66.7%, 98.6%, 90.3% and 93.6%, respectively.CONCLUSION: Multi-slice spiral CT imaging is simple, reliable, noninvasive and safe; moreover, it has a good potential for diagnosing especially excluding coronary arteriosclerotic heart disease, but still some limits.

ObjectiveTo observe the effect of botulinum toxin A (BTX-A) in rehabilitation training on cerebral palsy (CP).Methods47 CP children were randomly divided into the treatment group (32 cases) and control group (15 cases). Both groups were received rehabilitation training. But cases of the treatment group were injected with BTX-A in part of spastic muscles. Angles of inner contraction muscle (AICM) and activities of daily living (ADL) of two groups were observed for 6 months.ResultsImprovements of AICM and ADL in the treatment group were significantly better than that in the control group (P<0.01).Conclusions The rehabilitation training still is a kind of efficient treatment method. BTX-A injecting in part of spastic muscles is a kind of efficient assistant method and furnishes a better chance for rehabilitation training. Rehabilitation training combining with BTX-A injection can clearly curtail period of treatment, raise curative effect. BTX-A injection has significant applicable value in treatment on cerebral palsy.