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Objective:To evaluate the long-term clinical outcomes of total hip arthroplasty with the 4th ceramic-on-ceramic bearing in patients with history of hip injury.Methods:During December 2008 to December 2011, a total of 153 patients (157 hips) with history of hip injury were treated with 4th ceramic-on-ceramic bearing total hip arthroplasty. There were 25 cases (25 hips) were not followed up (16.3%). Ultimately, a total of 128 cases (132 hips) aged 49.26±14.18 (range 17-76) years including 87 males and 41 females were included in the study. In these patients, there were 15 cases (11.4%) with acetabular fracture, 90 cases (68.2%) with femoral fracture, 5 cases (3.8%) with hip dislocation and 22 cases (16.7%) with unknown history. Clinical outcomes, including operation duration, Harris score, range of motion, complications and noises, were evaluated. The survivorship was investigated by using Kaplan-Meier method.Results:The operation duration was 135.61±41.65 (range 64-320) min. The average follow-up duration was 9.62±0.82 (range 8.2-11.3) years. The Harris score increased from preoperative 44.07±19.71 to 94.03±4.10 at the last follow-up ( t=24.155, P<0.001). The range of hip motion increased from 75.90±28.05 degrees to 117.14±12.36 degrees ( t=13.176, P<0.001). There was no significant difference in Harris scores and ranges of motion among the groups with different history of fracture and dislocation. There were periprosthetic fracture in 1 case and hip dislocation in 2 cases. There was no periprosthetic hip infection or fracture of ceramic liner during the follow up. Thirteen cases (13 hips, 9.8%), including squeaking in 9 cases (6.8%) and clicking in 4 cases (3.0%), reported hip noise without pain and impairment on the quality of life. The survivorship was 100% at 10 years when regarded revision as an end point. However, the survivorship was 99.24% (95% CI: 97.8%, 100%) at 10 years when reoperation revision as an end point. Conclusion:Total hip arthroplasty with 4th ceramic-on-ceramic bearing could have excellent results for patients with a history of hip fracture or dislocation in the long-term follow-up. Although the prevalence of hip noise was about 10% in this cohort study, there was no impairment on the quality of life.
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Objective:To explore the clinical manifestations, diagnostic characteristics, treatment strategies and outcomes of patients with brucellaperi prosthetic joint infection (PJI).Methods:The medical records of 6 patients with brucella PJI in the First Medical Center of Chinese PLA General Hospital and the Third Hospital of Hebei Medical University from January 2010 to December 2018 were retrospectively analyzed, including 5 males and 1 female, aged 61.5±11.5 years (range 45-79 years) with body mass index 23.0±2.8 kg/m 2 (range 18.4-26.1 kg/m 2). Five cases lived in the countryside, 1 in the city. Four cases were farmers, while two cases were herder and unemployed. One case had contact history in the epidemic area, and 1 case had been in the slaughter industry. Three cases were with knee PJI, of which 1 patient underwent total knee arthroplasty due to knee joint villous nodular synovitis and 2 patients due to knee osteoarthritis. Three patients had hip PJI of which 1 patient underwent total hip arthroplasty due to spondylitis and hip ankylosis and 2 cases due to femoral head necrosis. Three cases were with acute PJI, while other 3 cases were with chronic PJI. Three cases showed fever, while 5 cases had local wounds swelling. A total of 4 cases were complicated with sinus tracts. Five cases had laboratory examinations on the day of admission of which 3 cases had elevated blood C-reactive protein (CRP) and 5 cases with increased erythrocyte sedimentation rate (ESR). Five cases were with increased blood interleukin-6 (IL-6), 2 cases with increased blood alanine transaminase (alanine transaminase, ALT). All cases had varying degrees of restricted movement of the affected joints. The normal range of motion of the hip joint was from 10° to 130°. The average range of motion of 3 patients with hip joint involvement was from 0° to 75°. The normal range of motion of the knee joint was 10°-135°. Three patients with knee joint involvement had an average range from -8° to 67°. One case showed loosening of the right hip prosthesis with infection and 1 case showed local soft tissue swelling. Other cases showed no obvious abnormalities in X-rays. Two patients who underwent frozen pathological examination during the operation had positive pathological neutrophilcounts. Four cases had positive Brucella culture in joint tissues or synovial fluid (1 case with mixed infection) and 2 cases had blood Brucella antibody positive. Results:Among the 3 cases of acute PJI, two of them were treated with debridement, antibiotics, irrigation and retention. One case was treated with two-stage revision. Among the 3 cases of chronic PJI, one was treated with two-stage revision and 2 were treated with one-stage revision. Brucella-specific antibiotics such as rifampicin and doxycycline were used in the antibiotic treatment with the course of antibiotics 3 to 12 weeks. At the time of discharge, the CRP and ESR dropped to the normal range (CRP 0-0.8 mg/dl, ESR 0-20 mm/1 h) in all cases except for the second case. Interleukin 6 was not tested in the sixth case before discharge. In the remaining 5 patients, the blood interleukin 6 fell to the normal range (0-5.9 pg/ml) in 2 cases, and the blood ALT was in the normal range (0-40 U/L) in 4 cases. The body temperature of the second case was 37.3 ℃, while the other cases dropped below 37.3 ℃. In the second case, fever occurred intermittently after surgery. Thus, the incisionwas reddened and swollen and exuded 2 months after the operation. The patient recovered after intravenous infusion of levofloxacin. Until the last follow-up, all patients had no recurrence of infection. Imaging examination comfirmed that the prosthesis was in good position.Conclusion:For patients with Brucella PJI, Brucella culture positive and Brucella antibody positive have specific diagnostic significance. Different surgical strategies will be adopt based on the patient's symptoms and the duration of infection. Surgery combined with Brucella specific antibiotic treatment can usually achieve satisfied therapeutic outcomes.
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Objective To investigate the clinical outcomes and complications of augmented antibiotic-loaded cement spacer in two-stage infected total hip arthroplasty with acetabular bone defect.Methods The periprosthetic infection (PJI) patients with acetabular bone defect were retrospectively reviewed from January 2007 to June 2016 in our hospital.A total of 26 patients (11 males and 15 females) were eligibly included in the present study.The mean age was 46.7 years old.The two-stage revision arthroplasty included implants removel,meticulous debridement,implantation of antibiotic-loaded cement spacer in firststage.After systemic therapy of antibiotics,the prosthesis was implanted in the second-stage.The supra-acetabular antibiotic cement shelf with screws was used to improve hip stability with acetabular wall defect.The handmade acetabular spacer was able to prevent femoral spacer ifto pelvis in patients with acetabular internal wall defect.The clinical outcomes and complications (spacer dislocation,spacer fracture and acetabular wear) were measured.Results The positive rate of bacteria culture was 80.8％ (21/26)and 57.7％ (15/26) patients were cultured with staphylococcus.The others were 2 fungus,2 Gram-positive rod,1 brucella,1 pseudomonas aeruginosa,1 escherichia coli,1 enterococcus faecalis,1 defective probiotics,1 serratiamarcescens and 1 Kocuriaroseus.Moreover,19.2％ (5/26) patients were mixed infection.There was one patient with spacer dislocation and two with spacer fracture.No patients were recurrent infection.Infection was controlled,and two-stage revision was successfully performed in 24 patients.Twenty-two patients were followed averaging 4.1 years (1-8) and the Harris Hip Score was significantly improved from 40.9± 14.0to 81.2± 11.2 at the final follow-up (P＜0.05).Conclusion The application of augmented antibiotic-loaded cement spacer has satisfactory clinical outcomes in PJI patients with acetabular bone defect.It can provide joint mobility and increase additional joint stability with decreased iatrogenic bone defect caused by acetabular wear.
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BACKGROUND:Staphylococcal infections and its biofilm formation can occur when orthopedic implants or wound is healing, and are regulated by bacterial population sensing mechanism. RNAIII inhibiting peptide intervenes the quorum-sensing system of staphylococcal and blocks the signal transduction among staphylococcal cells, and inhibits staphylococcal biofilm formation, and then prevents staphylococcal infections. OBJECTIVE:To investigate the influence of RNAIII inhibiting peptide on the adhesion of staphylococcus epidermis to the Hela cells. METHODS:The Hela cells were cultured in vitro. There were four groups in this study. In the blank group, saline with dimethyl sulfoxide was added in each wel . In the RNAIII inhibiting peptide group, dimethyl sulfoxide solution containing RNAIII inhibiting peptide was added. In the levofloxacin group, levofloxacin was added. In the combination group, the dose was in accordance with above methods. Using intergroup control method, the adhesion of staphylococcus epidermis to the Hela cells was compared under the effects of saline, RNAIII inhibiting peptide and levofloxacin and their combination. RESULTS AND CONCLUSION:In the blank group, abundant bacterial adhered to Hela cells. The number of adhered bacteria was significantly lower in each medicine group than in the blank group (P<0.001). The spot count was significantly lower in the levofloxacin group than in the RNAIII inhibiting peptide group (P<0.05). In the combination group, the number of bacteria adhered to Hela cells was decreased (P<0.01). Results verified that RNAIII inhibiting peptide effectively suppressed the adhesion of staphylococcus epidermis to the host cells, and showed synergistic effects on antibiotics.
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OBJECTIVE: To evaluate the histocompatibility of poly (lactic-co-glycolic acid)/RNA Ⅲ inhibiting peptide (PLGNRIP) sustained release microspheres.METHODS: The crude peptide comprising N to C-terminals was synthesized using Fmoc method. The crude synthetic RNAⅢ peptide was purified by reverse phase high performance liquid chromatography, followed by component harvesting according to ultraviolet absorption peak, and freeze-drying. PLGNRIP sustained release microspheres with a diameter of 50-70 pm were prepared using liquid-phase multiple emulsion method. The histocompatibility of PLGNRIP sustained release microscopes were preliminarily evaluated through the use of acute general toxicity test, MTT cytotoxicity test, intramuscular implantation test, sensitivity test, and pyrogen test.RESULTS: Acute general toxicity test results showed that all included animals survived and presented with no toxicosis reaction and obviously changed body mass. MTT cytotoxicity test results revealed that the average relative growth rate of cells from two eluents was over 85%, with cytotoxicity grade 1, which indicated no cytotoxicity. Intramuscular implantation tests showed that at 4 weeks after implantation of RiP powder or PLGNRIP microscopes, no obviously congested, degenerated, or necrotic tissue was observed. All RIP powder and a part PLGNRIP microscopes were degraded. Fibroblasts accounted for a large proportion in all cells. NO inflammatory cell infiltration, involving neutrophits and multinucleated giant celts, was observed. Sensitivity test rasults displayed that the average primary irritation index was 0.38, 0.33, arid 0.31 in the eluent stock solution, 2% dinitoflruorobenzene, and physiological saline-administerd groups, respectively. Pyrogen test results showed that fervescence of each rabbit in the experiment was under 0.5 ℃ and the sum of fervescence was under 1.3 ℃ .This is in coincidence with evaluation criteria of pyrogen test.CONCLUSION: PLGNRIP sustained release microspheras exhibit good histocompatibility.
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BACKGROUND: A new material of porous carbonated hydroxyapatite cement (PCHC) is discovered using foaming technique.The new material characterizes original solidification and forms porous structure.OBJECTIVE: To investigate the biomechanical effect of PCHC on repairing cancellous bone defect.METHODS: Among 30 New Land rabbits, 25 ones were considered as surgery group, whose bilateral condyles of femur was used to establish bone defect model (5.5 mm diameter and 12 mm depth). PCHC was implanted into the left side, which was considered as the experimental group, and carbonated hydroxyapatite cement (CHC) was implanted into the right side, which was considered as the control group. Another 5 rabbits were used as normal mechanical control group. Both PCHC and CHC were dip in simulated body fluid (SBF) to test mechanical intension. PCHC and CHC were then implanted into muscles of back in the surgery group. Rabbits Were-sacrificed after 2, 4, 8, 12, and 16 weeks postoperatively. Mechanical analysis was tested following intra-bone and intramuscular implantation, and compressive strength was then tested following dipping into SBF.RESULTS AND CONCLUSION: PCHC: Intra-bone mechanical strength was lower at 2 weeks, the lowest at 4 weeks, but then closed to intension of normal cancellated bone at 8 weeks, higher than normal cancellated bone at 12 weeks, and recovered to the level of normal cancellated bone at 16 weeks. CHC: Intra-bone strength was higher than that of PCHC at 2 weeks, decreased at 4 weeks, gradually increased at 8, 12, and 16 weeks, but still lower than intension of normal cancallated bone. Compressive strength of both PCHC and CHC was not changed following dipping in SBF; however, compressive strength was changed remarkably following intramuscular implantation. The results demonstrated that PCHC characterized by immobilization in situ and mechanical supporting. Thus it could be used for one kind of bone substitute material to repair the bone defect.
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BACKGROUND: Staphylococci inhibitor, RNAⅢ inhibiting peptide, has been firstly synthesized in China, while RNAIII inhibiting peptide/bioinspired phosphorylcholine-based cytomembrane coating (RIP/PC) has been also prepared.OBJECTIVE: To evaluate the blood compatibility of RIP/PC.DESIGN, TIME AND SETTING: A randomized controlled animal experiment was performed at Institute of Clinical Pharmacologic Research and Medical Animal Experimental Center of General Hospital of Chinese PLA from October 2005 to October 2007.MATERIALS: A total of 30 healthy adult New Zealand rabbits were provided by Animal Experimental Center of General Hospital of Chinese PLA.METHODS: The 316L stainless steel was dip into a mixture of 5 g/L quaternionic copolymer tetrahydrpfuran and 10% RNAⅢ inhibiting peptide to obtain stable polymer coating, which was extracted at density of 1 cm~2/mL in saline at 37 ℃ for 72 hours to get 100% eluent. The same volume of saline was added to make 50% eluent. The effects of RIP/PC on leukocytes, eryfhrocytes,and blood platelet of rabbits were detected via measuring prothrombin time and activated thrombin time during hemolysis test,hemagglutinatin test, and blood platelet aggregation test.MAIN OUTCOME MEASURES: Hemolytic ratio of erythrocytes, clotting time, prothrombin time, activated thrombin time, amounts of leukocytes, erythrocytes, and blood platelet, as well as blood platelet aggregation.RESULTS: Hemolysis test showed that the hemolytic ratio was 3.08% and 1.88% of 100% and 50% eluent, respectively; both the hemolytic ratios were < 5%, suggesting being coincidence with hemolytic requests of biological materials. The hemagglutinatin test showed that both 100% and 50% eluent did not have any effect on clotting time, prothrombin time, activated thrombin time,amounts of leukocytes, erythrocytes, and blood platelet, as well as blood platelet aggregation.CONCLUSION: The firstly synthesized RIP/PC has a good biocompatibility.
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OBJECTIVE: To evaluate blood compatibility of polyaiticglycolic acid/RNA Ⅲ inhibiting peptide (PLGA/RIP) delayed release microspheres.METHODS: ① Preparation of PLGA/RIP microspheres: The solid-phase synthesis (Fmoc) method was used to synthesize RIP crude sample from C end to N end; the synthesized crude peptide was purified by the reverse phase high performance liquid chromatography. According to UV absorption peak, the components were collected and freeze-dried, to obtain RIP purifications. Then liquid-phase multiple emulsion method was used to prepare PLGA/RIP microspheres at the diameter of 50-70 μm. ② Preparation of eluent: The PLGA/RIP microsphere powders were eluted with sterile physiological saline at 37 ℃, to prepare 1 g/L eluent; then 0.5 g/L eluent was obtained adding equal volume of sterile physiological saline. The hemolysis test, blood clotting test, and platelet aggregation test were conducted to measure prothrombin time and activated partial thromboplastin time, to observe the influence on rabbit leucocytes, erythrocytes and thrombocytes, and to preliminarily evaluate the blood compatibility of PLGA/RIP microspheres. RESULTS: ①The haemolysis rates of eluent stock solution and 0.5 g/L eluents were 3.24% and 2.67% respectively, which were in coincidence with the criteria of medical biomaterials, less than 5%. ② The eluent stock solution and 0.5 g/L eluents of PLGA/RIP microspheres had no significant effect on rabbit clotting time, prothrombin time and activated partial thromboplastin time, the number of rabbit leucocytes, erythrocytes and thrombocytes, as well as platelet aggregation.CONCLUSION: PLGA/RIP delayed release microspheres have a good blood compatibility.
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AIM: RNAⅢ inhibiting peptide (RIP) has been previously proved to possess good histocompatibility and safety for preventing and curing staphylococcal infection, and this study evaluated histocompatibility of polyaiticglycolic acid/RIP (PLGA/RIP) sustained release microsphere. METHODS: The experiment was performed in the Orthopedic Institute, Pharmacologic Research Institute and Animal Experimental Center of General Hospital of Chinese PLA from October 2005 to October 2007.①Preparation of PLGA/RIP: The solid-phase synthesis (Fmoc) method was used to synthesize RIP from C end to N end, then the synthesized peptide was purified by the reverse phase high performance liquid chromatography, and composition was collected by means of ultraviolet absorption peak. The purified RIP was obtained after freezing and drying. Liquid-phase multiple emulsion method was used to synthesize PLGA/RIP microsphere of 50-70 ?m diameter.②Acute general toxicity test was studied in PLGA/RIP. Effect of PLGA/RIP on the cell proliferation was detected with cytotoxicity test by MTT method. Intramuscular implanting test was used to observe the irritation reaction of muscles by implantation materials. Sensitivity test was used to observe the sensitization of PLGA/RIP. Changes of animal's body temperature were determined with pyrogen test. RESULTS: ①Acute general toxicity test: Neither toxicosis reaction nor animal death was found after animals were injected with 100% and 50% eluents of PLGA/RIP peritoneally. Animal's body weight was not changed significantly.②Cytotoxiciity test by MTT method: The average proliferation rate of cell in two kinds of eluents exceeded 85% and cytotoxicity was graded in 1 rank, indicating no cytotoxicity.③Intramuscular implanting test: At 4 weeks after RIP and PLGA/RIP were implanted into the animals, there was not obvious synathresis, denaturation or necrosis in tissues. No inflammatory cell infiltration occurred around the materials. There had been the fibrous capsules around the materials.④Sensitivity test: Average primary irritation index of three groups were 0.38, 0.33 and 0.31 respectively. There was no significant difference among three groups.⑤Pyrogen test: Fervescence of each animal in the experiment was under 0.5 ℃, confirming that the materials had no pyrogenic characteristics. This was in coincidence with evaluation criterion of pyrogen test. CONCLUSION: PLGA/RIP has good histocompatibility and safety, without general toxic reaction, cytotoxicity, immunological rejection, hypersensitive response or pyrogenic characteristics.
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OBJECTIVE:To evaluate the histocompatibility of poly(lactic-co-glycolic acid)/RNA Ⅲ inhibiting peptide(PLGA/RIP)sustained release microspheres.METHODS:The crude peptide comprising N to C-terminals was synthesized using Fmoc method.The crude synthetic RNAIII peptide was purified by reverse phase high performance liquid chromatography,followed by component harvesting according to ultraviolet absorption peak,and freeze-drying.PLGA/RIP sustained release microspheres with a diameter of 50-70?m were prepared using liquid-phase multiple emulsion method.The histocompatibility of PLGA/RIP sustained release microscopes were preliminarily evaluated through the use of acute general toxicity test,MTT cytotoxicity test,intramuscular implantation test,sensitivity test,and pyrogen test.RESULTS:Acute general toxicity test results showed that all included animals survived and presented with no toxicosis reaction and obviously changed body mass.MTT cytotoxicity test results revealed that the average relative growth rate of cells from two eluents was over 85%,with cytotoxicity grade 1,which indicates no cytotoxicity.Intramuscular implantation tests showed that at 4 weeks after implantation of RIP powder or PLGA/RIP microscopes,no obviously congested,degenerated,or necrotic tissue was observed.All RIP powder and a part PLGA/RIP microscopes were degraded.Fibroblasts accounted for a large proportion in all cells.No inflammatory cell infiltration,involving neutrophils and multinucleated giant cells,was observed.Sensitivity test results displayed that the average primary irritation index was 0.38,0.33,and 0.31 in the eluent stock solution,2% dinitoflruorobenzene,and physiological saline-administerd groups,respectively.Pyrogen test results showed that fervescence of each rabbit in the experiment was under 0.5℃ and the sum of fervescence was under 1.3℃.This is in coincidence with evaluation criteria of pyrogen test.CONCLUSION:PLGA/RIP sustained release microspheres exhibit good histocompatibility.
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OBJECTIVE To investigate the in vitro effect of 4 kinds of implant materials on the biofilm formation of Staphylococcus epidermidis.METHODS S.epidermidis was cultured,purified and identified.Susceptibility test was done for S.epidermidis and the ability to produce biofilm was proven.The test samples were made into wafer shape for titanium alloy,Co-Cr-Mo alloy,ultrahigh molecular weight polyethylene(UHMWPE)and home-made polymethyl methacrylate(PMMA).S.epidermidis was cultured with 4 kinds of test samples for 5 days respectively.Bacteria adhering on surfaces of 4 kinds of test samples were dissolved with trypsin,and then diluted into bacterial suspensions.Each bacterial suspension was inoculated quantitatively and CFU were counted.Biofilm on surfaces of 4 kinds of test samples prepared by vacuum drying method was observed with SEM.RESULTS The strain proven to be S.epidermidis,was resistant to semisynthetic penicillins,and could produce biofilm.CFU count showed that CFU were the most on the UHMWPE surface and the number of CFU were(24.96?1.459)?105.CFU were(17.44?1.883)?105 on the PMMP surface.(0.424?0.065)?105 CFU were discovered on the surfaces of titanium alloy and(0.382?0.075)?105 CFU on Co-Cr-Mo alloy.When each group compared with UHMWPE and domestic PMMA respectively,all P value was
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[Objective]To review our experience in treatine infection after total knee arthroplasty with debridement and component retention to determine To the feasibility,indication,factors related to success and failure,and the main points of technique.[Method]Since 1990 to 2004,9 patients were treated with debridement and component retention at our department.[Result]Four of 9 patients successfully retained their component at most recent follow-up,without ongoing infection(mean 18 months,range 10～25 months).We have not draw the statistically significant factors that related to successful and failure,but the factors such as acute infection,surfacing replacement,immediate debrided after onset of symptoms,and the bacteria sensitive to antibiotic were relate to success.[Conclusion]Debridement and component retention can be used in acute postoperative infection and later acute hematogenous infection after total knee replacement,but timing and indication must be chosen strictly.
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OBJECTIVE To determine the feasibility of clindamycin-loaded calcium phosphate cement(CLCPC) as a local antibiotic delivery system.METHODS The initial setting time(tI) and the final setting time(tF) were measured for 0%,2% and 5% CLCPC according to ASTM C266-89 method.Clindamycin concentrations eluting from the samples of 2% and 5% CLCPC in PBS were analyzed by HPLC at different times.The bacteriostasis tests were done by plate diffusion method for 2% and 5% CLCPC and 2% Palacos R-40 bone cement(PMMP) samples,and the diameters of the bacteriostasis ring and bacteriostasis duration were observed.The setting product and crystal size of 0%,2% and 5% CLCPC were analyzed and observed by X-ray diffraction(XRD) and scanning electron microscopy(SEM).RESULTS The setting time could be shortened by adding clindamycin(tI,tF) of 2% and 5% CLCPC.Clindamycin was with burst-release from CLCPC within the intial 6-hour period and the release rate slowed down on 4th day.Clindamycin could still release until to the 42th day.The ring of 2% Palacos R-40 bone cement(PMMP) bacteriostasis was smaller than that of 2% CLCPC,and the ring of 2% CLCPC bacteriostasis was smaller than that of 5%CLCPC.The bacteriostasis still existed to the 42th day of test for 2% and 5%CLCPC and 2% Clindamycin-loaded Palacos R-40 bone cement(CLPMMP).From the 30th day,many bacterial colonies were seen in the culture media laying 2%CLPMMP sample.On the contrary,bacterial colony was not found in the media putting 2% and 5%CLCPC.XRD and SEM showed that clindamycin did′t have an influence on setting product,crystal size and structure of CPC.CONCLUSIONS Clindamycin-loaded calcium phosphate cement can be used as a local antibiotic delivery system.
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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.
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Review the microbiological result of infected total hip replacement cases we found that positive rate of preoperative and intraoperative culture is only 77.1% and 78.5%, and the coincidence rate of preoperative and intraoperative culture results only 59.1%. In all organisms about 56.2% and 46% is staphylococcus of preoperative and intraoperative culture respectively. Staphylococcus can form massive biofilm. The result shows that in total hip replacement infection, the accurate rate of preoperative and intraoperative culture is low and need to improve, and the virulent and resistance organisms maintain a high rate lead to it is hard to cure.