Objective To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate.Methods A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software.STL data were input into 3D printer to print 1∶1 clavicle model and proximal clavicle anatomical plate.The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging.Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded.Results The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orienta-tion of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good.Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively.Conclusion The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.

Objective To explore clinical effect of closed reduction percutaneous elastic intramedullary nail assisted by arthrography in the treatment of radial neck fracture in children.Methods A retrospective analysis was performed on 23 chil-dren with radial neck fracture treated with arthrography assisted closed reduction and percutaneous elastic intramedullary nail internal fixation(arthrography with elastic nail group)from January 2019 to December 2022,including 12 males and 11 fe-males,aged from 2 to 12 years old with an average of(7.36±1.89)years old;According to Judet fracture types,14 children were type Ⅲ and 9 children were type Ⅳ.In addition,23 children with radial neck fracture were selected from January 2015 to December 2018 who were treated with closed reduction and percutaneous elastic intramedullary nail fixation(elastic nail group),including 11 males and 12 females,aged from 2 to 14 years old with an average of(7.50±1.91)years old;Judet classi-fication included 15 children were type Ⅲ and 8 children were type Ⅳ.Operative time and intraoperative fluoroscopy times were compared between two groups.Metaizeau evaluation criteria was used to evaluate fracture reduction,and Tibone-Stoltz evaluation criteria was used to evaluate functional recovery of elbow between two groups.Results Both groups were followed up for 12 to 24 months with an average of(16.56±6.34)months.Operative time and intraoperative fluoroscopy times of elastic nail group were(56.64±19.27)min and(21.13±7.87)times,while those of joint angiography with elastic nail group were(40.33±1 1.50)min and(12.10±3.52)times;there were difference between two groups(P＜0.05).According to Metaizeau evaluation,11 patients got excellent result,9 good and 3 fair in joint angiography with elastic nail group,while in elastic nail group,5 ex-cellent,13 good,4 acceptable,and 1 poor;the difference between two groups was statistically significant(P＜0.05).According to Tibone-Stoltz criteria,14 patients got excellent result,8 good,and 1 fair in joint arthrography with elastic nail group;while in elastic nail group,12 patients got excellent result,9 good,1 fair and 1 poor;there was no significant difference between two groups(P＞0.05).Conclusion Compared to percutaneous elastic intramedullary nail fixation,closed reduction assisted by arthrography has advantages of reduced operation time,decreased intraoperative fluoroscopy frequency,and improved fracture reduction.Arthrography enables clear visualization of the anatomical structures of radius,head,neck,bone,and cartilage in children,facilitating comprehensive display of fracture reduction and brachioradial joint alignment.This technique more pre-cisely guides the depth of elastic intramedullary nail implantation in radius neck,thereby enhancing surgical efficiency and success rate.

Objective To explore establishment and finite element analysis of personalized proximal clavicular anatomical plate screw fixation model.Methods A 40-year-old male healthy volunteer was selected and the finite element analysis modules of 3D reconstruction software Mimics 15.01,Hypermesh 2019 and Abaqus 2020 were used.The finite element model of anatomic plate at the proximal clavicle was established,and a vertical load of 250 N was applied to the distal end of long axis of clavicle about 15 mm,then the overall structure,plate and screw displacement cloud image,Mises stress distribution were ob-served.Results The displacement distribution of the overall structure shows the maximum displacement was distributed on the distal clavicle.Under the four conditions of normal upper limb weight,longitudinal clavicle fracture,oblique fracture and shoulder impact violence during fall,longitudinal clavicle fracture and oblique fracture,the maximum displacement were 1.04 mm,1.03 mm,1.35 mm and 1.33 mm,respectively.The displacement cloud map of titanium alloy steel plate showed the largest displacement was distributed near the distal clavicular bone,and the maximum displacement were 0.89 mm,0.88 mm,1.10 mm and 1.09 mm,respectively.The displacement cloud map of titanium alloy screw showed the largest displacement was distribut-ed at the root of the distal screw,and the maximum displacement were 0.88 mm,0.87 mm,1.08 mm and 1.06 mm,respectively.Mises stress distribution showed the maximum stress was mainly distributed on titanium alloy plates and screws,and the stress on the clavicle was very small.Mises stress distribution cloud showed the maximum Mises stress was distributed at the second row of screw holes near the clavicle,and the maximum Mises stress were 673.1,678.1,648.5,654.4 MPa,respectively.The maximum stresses of titanium alloy screws were 414.5,417.4,415.8 and 419.7 MPa,respectively.Conclusion The biomechan-ical changes of personalized proximal clavicular anatomical plates are demonstrated by using 3D finite element method to pro-vide biomechanical data for personalized proximal clavicular anatomical plates.

Objective To compare the incidence of superior facet joint violation in patients with different preoperative diagnoses in posterior lumbar interbody fusion.Methods The clinical data of 320 patients who underwent posterior lumbar interbody fusion from January 2018 to December 2021 in our hospital were retrospectively analyzed,and the preoperative diagnoses were including the lumbar disc herniation/lumbar spinal canal stenosis,degenerative lumbar spondylolisthesis,and isthmic lumbar spondylolisthesis.The superior facet joint violation was graded based on the postoperative lumbar CT,the incidences of superior facet joint intrusion of patients with different preoperative diagnosis were compared,and the correlations between relevant parameters(including the apical vertebrae of fixation segments,facet joint angle,depth of lamina,introversion angle of pedicle screw,axial diameter of facet joint,and slippage length of vertebrae)with superior facet joint violation and preoperative diagnoses were investigated.Results The incidence of superior facet joint violation in the patients with isthmic lumbar spondylolisthesis(57.4%)was higher than that in the patients with lumbar disc herniation/lumbar spinal canal stenosis(41.2%)and degenerative lumbar spondylolisthesis(35.9%),with statistically significant differences(P<0.05).The apical vertebrae of fixation segments,facet joint angle,axial diameter of facet joint and introversion angle of pedicle screw were related with the occurrence of superior facet joint violation(P<0.05).There were statistically significant differences in the facet joint angle,axial diameter of facet joint and apical vertebrae of fixation segments among patients with different preoperative diagnoses(P<0.05).Conclusion Patients with isthmiclumbar spondylolisthesis are more likely to occur superior facet joint violation than patients with lumbar disc herniation/lumbar spinal canal stenosis and degenerative lumbar spondylolisthesis.

Objective To explore the effect of cardiac shock wave therapy(CSWT)on ST deviation of electrocardiogram and myocardial perfusion imaging in coronary artery disease(CAD)patients.Methods CAD patients who received CSWT in Cardiology Department of Beijing Hospital from December 2016 to August 2022 were enrolled.Three months of CSWT were conducted with a total of 9 times shock wave treatment.Clinical data,myocardial perfusion imaging data and stress electrocardiogram data were collected.Myocardial perfusion score,electrocardiographic data were compared before and after CSWT.Results A total of 55 patients were finally enrolled.There were 43 male and 12 female patients with an average age of(67.45±8.96)years old.ST deviation on 12 leads of electrocardiogram did not show significant difference before and after CSWT.Myocardial perfusion imaging showed global stress perfusion score(P=0.031)and reverse perfusion score(P=0.024).Global rest ischemia score reduced after CSWT(P=0.034).Target stress perfusion score(P=0.002),target reverse perfusion score(P=0.002),target reverse ischemic area(P=0.001)were improved after CSWT.Conclusions CSWT may not influence ST deviation of electrocardiogram,but may improve myocardial ischemia in CAD patients,

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.