The fluorescence characteristics of reaction products of sparfloxacin with halide (F, Cl, Br, I) have been studied. It was found that sparfloxacin was oxidized by nitrous acid then reacted with halide further to formstrong fluorescence substances in acid media. Their fluorescence intensitites enhanced with aggrandizing of atom radii of halides, which could emit the strong fluorescence 58～151 fold more than that of sparfloxacin itself. Thus a new sensitive method for the direct determination of sparfloxacin in human urine by derivative-synchronous fluorescence was presented. A plausible mchanism was proposed to explin this behavior.

Objective To evaluate effect of two-stage exchange total hip arthroplasty (THA) using an antibiotic-loaded cement spacer in the treatment of hip infection secondary to hip surgery.Methods From January 2005 to January 2010,6 consecutive patients with infected hip secondary to hip surgery,including 2 males and 4 females,aged from 43 to 68 years (average,59.7±9.2 years) were treated with two-stage exchange THA.There were 3 cases of femoral neck fracture treated with compression screws fixation,1 case of femoral head necrosis treated with bone graft,and 2 cases of early stage femoral head necrosis treated with core decompression and local interventional therapy respectively.Debridement and insertion of antibioticloaded cement spacer was performed in the first stage.After eradication of infection,it was converted to THA in the second stage.All patients were followed up regularly.Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were tested.Harris score was used to evaluate the function of the hips.Results All patients were followed up for an average of 46 months (range,24 to 81 mouths).Five of 6 patients were successfully converted to THA after an average of 14 weeks.One patient accepted the second debridement and reinsertion of a spacer owing to the abnormal values of ESR and CRP; this case was converted to THA successfully 12 weeks after the second debridement.Harris hip score improved from preoperative 35.6±3.3 to 57.8±5.4 between the two stages and 92.3±5.7 at final follow-up.One patient suffered deep vein thrombosis in the infected extremity and pulmonary embolism.There was no reinfection after THA.Conclusion Twostage exchange THA using an antibiotic-loaded cement spacer can obtain satisfactory results for the treatment of hip infection secondary to the hip surgery.

ObjectiveTo explore the magnitude of the deformation of Durom cup after press-fit implantation in cadaver models and to investigate which part of the cup would deform the most.Methods Three fresh adult cadaver pelves were harvested and were cleaned of soft tissue,preserving the sacrospinous and sacrotuberous ligaments.Bilateral acetabular replacements in all cadaver pelves were performed by a senior surgeon.All acetabulums were reamed with corresponding reamers,and the direction of reaming was 40°to 45° of abduction and 15° to 20° of anteversion.Larger reamers were used sequentially until the anterior and posterior walls were firmly engaged.Six Durom cups were implanted.The deformation of each cup was detected by 3D Digital Image Correlation (3D DIC) method,and the magnitude and the parts of the deformation were recorded.ResultsThe diameters of cups were 50 mm in 2,52 mm in 2 and 54 mm in 2,respectively.All cups generated different degree of deformation,which were mostly located in the posterior-superior quadrant and the areas of the ramus of ischium.After measuring the maximum deformed areas for three times,it was found that the localized depression deformation occurred in all cups.The average deformation value was (41.73±8.86) μm (range,29.91-49.43 μm).There was no significant change in deformation value 24 hours after press-fit implantation and 7 days after removing the cups.ConclusionDurom large diameter metal acetabular component will generate deformation during the press-fit implantation.And the deformation may play an important role in more wear and more ions release.

Objective To compare the serum metal ion levels and host immunologic response of patients received non-modular,large-head metal-on-metal total hip arthroplasty (THA,Durom) with those received modular titanium acetabular component (Trilogy) using conventional head sizes and metal-on-highly cross-linked polyethylene articulations at mean 2-year follow-up interval.Methods A continuous series of 32 consecutive patients (32 hips) accepted THA with a Durom large head metal-on-metal articulation between January 2008 and December 2010 was as study group (Durom Group).From all the patients who received THA with Trilogy prosthesis at the same period,32 patients matched the Durom group in age,gender and body mass index (BMI) were chosen to form the Trilogy group.Another 32 healthy volunteers also matched the Durom group were chosen to form the control group.At the final follow-up,the serum metal ion levels,host immunologic response were evaluated.Results The mean follow-up time for Durom group was 24.9 months (range,15-34 months) compared to 25.53 months (range,15-48 months) for Trilogy group.Co and Cr levels in Durom group were 4.33 and 1.95 times as high as those in Trilogy group.There was no statistically significant difference in serum C3,C4,IgA,IgG,IgM value in three groups.CD3+,CD4+ and CD8+cells in Durom group decreased significantly compared with Trilogy and control groups.The interferon-γ(IFN-γ) level in Durom group was significantly higher than that in Trilogy and control groups.Conclusion The serum cobalt and chromium levels in patients received Durom metal-on-metal THA elevated significantly in early period.Meanwhile,some amount of impact on host cell mediated immunity occurred.

Objective To investigate the method and efficacy in treating acetabular bone defects by the use of titanium wire mesh and impact bone allograft in revision total hip arthroplasty.Methods Twenty-two patients (22 hips) with acetabular bone defects in revision total hip arthroplasty were treated with wire mesh and impact bone allograft from January 2008 to December 2013.There were 7 males and 15 females in the present study.The average age of the patients at the surgery was 64.8 (37-78) years.According to Paprosky classification,there were 9 cases of type ⅡA,4 cases of ⅡB,7 cases of ⅡC and 2 cases of ⅢB.Twenty cases with aseptic loosen and 2 with periprosthetic infection were underwent revision surgery.Deep frozen cancellous bone allograft was sterilized and morselized to particles with the size of 7 to 10 mm.After removal of loosed acetabular component,the bone grafts were impacted into the acetabular defects area to restore the bone quantity.Titanium wire mesh with appropriate diameter was chosen to fix on impacted bone graft and fixed acetabulum with screws.Polyethylene cup was cemented in the mesh wire with proper position.Harris hip score system was used to evaluate the hip joint function.The AP pelvis X-ray was taken at 1 week,3 months,12 months and annually thereafter postoperatively to evaluate the rotation center,fusion of the bone graft and loosening of cup.Results All patients were followed up with the average period 5.1 years (3-7 years).The average Harris hip score before revision was 43.75±13.45,while the score was 85.33±7.84 at last follow-up (t=7.930,P=0.000).The average height of hip rotation center of surgical side was 3.49±0.77 cm before surgery,while its height at last follow-up was 2.22±0.22 cm (t=4.390,P=0.005).The distance between hip rotation center and the base of acetabulum was 3.54±0.45 cm before surgery,while its value was 3.52± 0.76 cm at last follow-up.All the bone grafts came to infusion with the average time 12 months (9-15 months).There was no case with cup migration more than 4 mm or rotation greater than 5° at last follow-up.One patient had the symptom of sciatic nerve injury.No case was with infection or dislocation.Conclusion In the treatment of acetabular bone defects,wire mesh and impact bone allograft with cemented cup in revision total hip arthroplasty can reconstruct hip rotation center and the acetabular bone quantity effectively.Satisfied early-midterm curative effects could be acquired by using this method.

Objective To compare the clinical safety and efficacy of simultaneous bilateral total knee arthroplasty (TKA) and staged bilateral TKA in treatment of both knee osteoarthritis.Methods A total of 119 patients (14 males,105 females) with both knee osteoarthritis who underwent TKA from March 2005 to March 2012 were retrospectively analyzed.Their ages ranged from 30 to 81 years with the average age of 65.23±6.33 years.The patients were divided into three groups according to different treaments:simultaneous bilateral TKA group,staged bilateral TKA group during the same hospitalization period and staged bilateral TKA group in two separate hospitalization periods.All the procedures were performed by the same surgeons and the same type of prostheses (LPS-Flex,Zimmer,US) were implanted.Differences of preoperative factors (age,height,body mass in dex and complications),treatment factors (preoperative hemoglobin,operation time,drainage volume,blood transfusion volume,total hospitalization time and total hospitalization costs) and postoperative curative effects (HSS scores,WOMAC scores and ROM)among three groups were compared.The analysis of viariace,LSD-t test and x2 test were used for data analysis.Results The differences of gender composition,body mass index,preoperative hemoglobin were not statistically significant among three groups (P＞0.05).The patientsin simultaneous bilateral TKA group were younger,and havelower incidence ofpreoperative complications (P＜0.05).The differences of post-operative HSS scores,WOMAC scores and ROM were not statistically significant among the three groups (P＞0.05).Although the total hospitalization time,operation time were shorter,and the hospitalization costs were significant ly lower in simultaneous bilateral TKA group,the total drainage volume,the total blood transfusion volume and incidence of postoperative complication rate were higher in this group than those of the other two grops (P＜0.05).Conclusion Due to great impact on patients' physiological conditions,more postoperative complication occurrence and high risk of periprosthetic infection,the decision of simultaneous bilateral TKA should be made cautiously.

Objective To determine the incidence of avascular necrosis after closed reduction and cannulated compression screws fixation of intra-capsular femoral neck fracture and to investigate the multiple factors correlated to avascular femoral head necrosis.Methods All the patients of intra-capsular femoral neck fracture who accepted closed reduction and cannulated compression screws fixation between 2001 and 2010 in Jiangsu Province were reviewed in multi-centers retrospectively.The multiple factors were analyzed including age,gender,affected side,mechanism of injury,fracture classification,procedure delay,quality of reduction,time of full-weight-bearing,configuration of the screws and removal of the screws.Multiple correlation factors were analyzed with SPSS 13.0 statistic system.Results Complete case records were documented in 1849 cases who were followed up for an average 6.5±2.7 years (range,2-10 years).Avascular necrosis occurred in 246 cases (13.3％).The average time of diagnosis of avascular necrosis was 17±4.6months (range,8-72 months) after injury.The average Harris score of the hips which didn't develop to avascular necrosis was 93.8±8.9 (range,78～100) at the last follow up.Multiple correlation factors analysis indicated that displacement degrees of fracture and the quality of reduction were significantly correlated to the incidence of avascular necrosis (OR=2.078,3.423).Conclusion Closed reduction and cannulated compression screws fixation after the intra-capsular femoral neck fracture can get satisfactory results.Displacement degrees of fracture and the quality of reduction are significantly correlated to the incidence of avascular femoral head necrosis.