BACKGROUND:Periprosthetic fracture of the femoral of the knee after total knee arthroplasty is one of the common complications,and there is a lack of biomechanical research on the periprosthetic fractures of the femoral of the knee under different bone strength conditions.The three-dimensional finite element analysis can provide a biomechanical basis for clinical practice. OBJECTIVE:To investigate the biomechanical changes of anterior femoral notching after total knee arthroplasty under different bone strengths,and to provide a mechanical basis for the clinical prevention of supracondylar femoral periprosthetic fractures after knee arthroplasty. METHODS:The femoral CT data of healthy adults were obtained,and the three-dimensional model of femoral lateral replacement of the knee joint was established by Mimics,Geomagic studio,and Solidworks software.Anterior femoral notching models of different depths were constructed,and the models were imported into ANSYS software to analyze the changes of biological stress on the femoral condyle with different bone strengths and different anterior femoral notching depths.The stress changes of the femoral anterior condyle section after and before the filling of anterior femoral notching with bone cement were analyzed. RESULTS AND CONCLUSION:(1)Under any bone strength,the supracondylar stress increased with the depth of anterior femoral notching.In normal bone conditions,there was a stress abrupt change point when the anterior femoral notching depth was between 3 mm and 4 mm.In the case of osteoporosis,there was a stress abrupt point when the anterior femoral notching depth was between 2 mm and 3 mm.(2)When anterior femoral notching occurred during knee arthroplasty and the depth exceeded the thickness of the bone cortex,the supracondylar stress of the femoral gradually increased as the bone strength decreased.(3)The stress of the anterior femoral condyle section decreased when the model with an anterior femoral notching depth of 3 mm was filled with bone cement.(4)The results show that anterior femoral notching should be avoided during knee arthroplasty,especially in patients with osteoporosis.If anterior femoral notching occurs during surgery,bone cement can be used to evenly fill the anterior femoral notching to reduce the supracondylar stress of the femur and reduce the incidence of periprosthetic fractures of the femoral joint

Infection Prevention and Control(IPC)programs are crucial for prevention of hospital-associated infec-tions(HAIs),health and safety of patients and health care workers.The major task confronting the health care is to effectively carry out the IPC programs so as to raise the efficiency and quality of management of HAIs.In recent years,the rapid development of artificial intelligence(AI)technology has provided new ideas for the management of HAIs.The application and progress of research on application of AI technologies such as machine learning,nat-ural language processing and computer vision in surveillance,early warning,diagnosis,prevention and control,smart medical equipment and management of antibiotics were reviewed in the article.Meanwhile,the problems and challenges confronting the AI application,such as technical breakthroughs,data privacy and health care work-ers' acceptance,were also expounded.In the future,it is necessary to push forward the technology research and development,establish the safe and reliable data management system,increase the experience of health care work-ers and energize the interdisciplinary cooperation on IPC.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective:To analyze the characteristics of anonymous online dating and related factors of not being tested for HIV among men who have sex with men and to provide the basis for developing targeted HIV prevention strategies and intervention measures.Methods:Using a cross-sectional study design, respondents were recruited with the assistance of MSM social organizations from April to July 2023 in eight cities in Shandong Province. Snowball sampling, activity venues, and networks were employed, targeting a sample size of 400 people per city. A face-to-face questionnaire survey collected data on sociodemographic characteristics, drug use, sexual intercourse, and online informed dating. Blood samples were also collected for HIV and syphilis antibody testing.Results:In the past six months, 2 787 MSM sought homosexual partners through the Internet, and 78.26% (2 181/2 787) chose to make anonymous online dating. Before having homosexual sex with online sexual partners, 10.41% (290/2 787) of them did not ask each other about HIV infection status and 33.37% (930/2 787) of them not being tested for HIV. There were statistically significant differences in the distribution of age, marital status, household registration, education level, sexual orientation, ways to find male sexual partners, not asking online sexual partners about their HIV status before sexual intercourse, no mutual HIV testing with online sexual partners before sexual intercourse, and syphilis antibody between anonymous and non-anonymous online dating persons (all P<0.05). The results of multivariate logistic regression analysis showed that <25 years old (a OR=1.43, 95% CI: 1.15-1.77) and ≥35 years old age group (a OR=1.61, 95% CI: 1.29-2.01), people with no AIDS knowledge (a OR=2.37, 95% CI: 1.25-4.49), drug users (a OR=1.38, 95% CI: 1.17-1.63), online dating anonymous (a OR=2.19, 95% CI: 1.76-2.73), HIV antibody positive (a OR=3.61, 95% CI: 2.22-5.88) and no intervention services in the last 1 year (a OR=1.58, 95% CI: 1.05-2.38) were the related factors of MSM not being tested for HIV before having sexual intercourse through online dating. Conclusions:The phenomenon of anonymous online dating was common among MSM in Shandong Province, and the proportion of MSM not being tested for HIV before having sexual intercourse through anonymous online dating was relatively high. It is necessary to strengthen health publicity and promote informed dating in MSM.

Objective:To analyze the characteristics of anonymous online dating and related factors of not being tested for HIV among men who have sex with men and to provide the basis for developing targeted HIV prevention strategies and intervention measures.Methods:Using a cross-sectional study design, respondents were recruited with the assistance of MSM social organizations from April to July 2023 in eight cities in Shandong Province. Snowball sampling, activity venues, and networks were employed, targeting a sample size of 400 people per city. A face-to-face questionnaire survey collected data on sociodemographic characteristics, drug use, sexual intercourse, and online informed dating. Blood samples were also collected for HIV and syphilis antibody testing.Results:In the past six months, 2 787 MSM sought homosexual partners through the Internet, and 78.26% (2 181/2 787) chose to make anonymous online dating. Before having homosexual sex with online sexual partners, 10.41% (290/2 787) of them did not ask each other about HIV infection status and 33.37% (930/2 787) of them not being tested for HIV. There were statistically significant differences in the distribution of age, marital status, household registration, education level, sexual orientation, ways to find male sexual partners, not asking online sexual partners about their HIV status before sexual intercourse, no mutual HIV testing with online sexual partners before sexual intercourse, and syphilis antibody between anonymous and non-anonymous online dating persons (all P<0.05). The results of multivariate logistic regression analysis showed that <25 years old (a OR=1.43, 95% CI: 1.15-1.77) and ≥35 years old age group (a OR=1.61, 95% CI: 1.29-2.01), people with no AIDS knowledge (a OR=2.37, 95% CI: 1.25-4.49), drug users (a OR=1.38, 95% CI: 1.17-1.63), online dating anonymous (a OR=2.19, 95% CI: 1.76-2.73), HIV antibody positive (a OR=3.61, 95% CI: 2.22-5.88) and no intervention services in the last 1 year (a OR=1.58, 95% CI: 1.05-2.38) were the related factors of MSM not being tested for HIV before having sexual intercourse through online dating. Conclusions:The phenomenon of anonymous online dating was common among MSM in Shandong Province, and the proportion of MSM not being tested for HIV before having sexual intercourse through anonymous online dating was relatively high. It is necessary to strengthen health publicity and promote informed dating in MSM.

Infection Prevention and Control(IPC)programs are crucial for prevention of hospital-associated infec-tions(HAIs),health and safety of patients and health care workers.The major task confronting the health care is to effectively carry out the IPC programs so as to raise the efficiency and quality of management of HAIs.In recent years,the rapid development of artificial intelligence(AI)technology has provided new ideas for the management of HAIs.The application and progress of research on application of AI technologies such as machine learning,nat-ural language processing and computer vision in surveillance,early warning,diagnosis,prevention and control,smart medical equipment and management of antibiotics were reviewed in the article.Meanwhile,the problems and challenges confronting the AI application,such as technical breakthroughs,data privacy and health care work-ers' acceptance,were also expounded.In the future,it is necessary to push forward the technology research and development,establish the safe and reliable data management system,increase the experience of health care work-ers and energize the interdisciplinary cooperation on IPC.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

With the increasing proportion of human papilloma virus(HPV)infection in the pathogenic factors of oro-pharyngeal cancer,a series of changes have occurred in the surgical treatment.While the treatment mode has been im-proved,there are still many problems,including the inconsistency between diagnosis and treatment modes,the lack of popularization of reconstruction technology,the imperfect post-treatment rehabilitation system,and the lack of effective preventive measures.Especially in terms of treatment mode for early oropharyngeal cancer,there is no unified conclu-sion whether it is surgery alone or radiotherapy alone,and whether robotic minimally invasive surgery has better func-tional protection than radiotherapy.For advanced oropharyngeal cancer,there is greater controversy over the treatment mode.It is still unclear whether to adopt a non-surgical treatment mode of synchronous chemoradiotherapy or induction chemotherapy combined with synchronous chemoradiotherapy,or a treatment mode of surgery combined with postopera-tive chemoradiotherapy.In order to standardize the surgical treatment of oropharyngeal cancer in China and clarify the indications for surgical treatment of oropharyngeal cancer,this expert consensus,based on the characteristics and treat-ment status of oropharyngeal cancer in China and combined with the international latest theories and practices,forms consensus opinions in multiple aspects of preoperative evaluation,surgical indication determination,primary tumor re-section,neck lymph node dissection,postoperative defect repair,postoperative complication management prognosis and follow-up of oropharyngeal cancer patients.The key points include:① Before the treatment of oropharyngeal cancer,the expression of P16 protein should be detected to clarify HPV status;② Perform enhanced magnetic resonance imaging of the maxillofacial region before surgery to evaluate the invasion of oropharyngeal cancer and guide precise surgical resec-tion of oropharyngeal cancer.Evaluating mouth opening and airway status is crucial for surgical approach decisions and postoperative risk prediction;③ For oropharyngeal cancer patients who have to undergo major surgery and cannot eat for one to two months,it is recommended to undergo percutaneous endoscopic gastrostomy before surgery to effectively improve their nutritional intake during treatment;④ Early-stage oropharyngeal cancer patients may opt for either sur-gery alone or radiation therapy alone.For intermediate and advanced stages,HPV-related oropharyngeal cancer general-ly prioritizes radiation therapy,with concurrent chemotherapy considered based on tumor staging.Surgical treatment is recommended as the first choice for HPV unrelated oropharyngeal squamous cell carcinoma(including primary and re-current)and recurrent HPV related oropharyngeal squamous cell carcinoma after radiotherapy and chemotherapy;⑤ For primary exogenous T1-2 oropharyngeal cancer,direct surgery through the oral approach or da Vinci robotic sur-gery is preferred.For T3-4 patients with advanced oropharyngeal cancer,it is recommended to use temporary mandibu-lectomy approach and lateral pharyngotomy approach for surgery as appropriate;⑥ For cT1-2N0 oropharyngeal cancer patients with tumor invasion depth＞3 mm and cT3-4N0 HPV unrelated oropharyngeal cancer patients,selective neck dissection of levels ⅠB to Ⅳ is recommended.For cN+HPV unrelated oropharyngeal cancer patients,therapeutic neck dissection in regions Ⅰ-Ⅴ is advised;⑦ If PET-CT scan at 12 or more weeks after completion of radiation shows intense FDG uptake in any node,or imaging suggests continuous enlargement of lymph nodes,the patient should undergo neck dissection;⑧ For patients with suspected extracapsular invasion preoperatively,lymph node dissection should include removal of surrounding muscle and adipose connective tissue;⑨ The reconstruction of oropharyngeal cancer defects should follow the principle of reconstruction steps,with priority given to adjacent flaps,followed by distal pedicled flaps,and finally free flaps.The anterolateral thigh flap with abundant tissue can be used as the preferred flap for large-scale postoperative defects.

Objective To explore the safety and efficacy of neoadjuvant chemotherapy(NAC)combined with immunotherapy before radical cystectomy plus pelvic lymph nodes dissection(RC-PLND)for muscle-invasive bladder cancer(MIBC).Methods The clinical data of 101 patients with MIBC who underwent neoadjuvant therapy followed by RC-PLND in the Department of Urology,the First Affiliated Hospital of Xi'an Jiaotong University during Jan.2019 and Dec.2023 were retrospectively analyzed,including 71 patients(70.3％)who received NAC(NAC group)and 30(29.7％)who received NAC combined with immunotherapy(NAC combine immunotherapy group).The clinical and pathological data and adverse events during neoadjuvant therapy were compared.Logistic regression analysis was used to explore the independent predictors of pathological complete response(pCR)and pathological partial response(pPR).Results There were no significant differences in the baseline data between the two groups(P＞0.05).However,the proportion of multiple tumors in patients receiving NAC before surgery was significantly higher than that in the NAC combined immunotherapy group(69.0％vs.46.7％,P=0.034).Compared with NAC group,NAC combined with immunotherapy group had significantly improved rate of pathological downstaging and pPR(60.6％vs.83.3％,P=0.026;45.1％vs.70.0％,P=0.022).Furthermore,the rate of pCR in patients undergoing NAC combined immunotherapy was higher than those undergoing NAC,but the difference was not significant(53.3％vs.33.8％,P=0.067).Logistic regression analysis revealed that clinical T-stage and tumor diameter were independent predictors of pCR and pPR(P＜0.05).In addition,the most common adverse events during neoadjuvant therapy were anemia,decreased white blood cells,nausea,and vomiting,but most of them were grade 1-2 and could be relieved through symptomatic treatment.Conclusion NAC combined with immunotherapy is safe and effective,which can improve the rate of pathological downstaging,pPR and pCR,without increasing the incidence of adverse reactions.

Objective:To investigate the current status of endoscopic treatment for gastroesophageal varices in portal hypertension in China, and to provide supporting data and reference for the development of endoscopic treatment.Methods:In this study, initiated by the Liver Health Consortium in China (CHESS), a questionnaire was designed and distributed online to investigate the basic condition of endoscopic treatment for gastroesophageal varices in portal hypertension in 2022 in China. Questions included annual number and indication of endoscopic procedures, adherence to guideline for preventing esophagogastric variceal bleeding (EGVB), management and timing of emergent EGVB, management of gastric and isolated varices, and improvement of endoscopic treatment. Proportions of hospitals concerning therapeutic choices to all participant hospitals were calculated. Guideline adherence between secondary and tertiary hospitals were compared by using Chi-square test.Results:A total of 836 hospitals from 31 provinces (anotomous regions and municipalities) participated in the survey. According to the survey, the control of acute EGVB (49.3%, 412/836) and the prevention of recurrent bleeding (38.3%, 320/836) were major indications of endoscopic treatment. For primary [non-selective β-blocker (NSBB) or endoscopic therapies] and secondary prophylaxis (NSBB and endoscopic therapies) of EGVB, adherence to domestic guideline was 72.5% (606/836) and 39.2% (328/836), respectively. There were significant differences in the adherence between secondary and tertiary hospitals in primary prophylaxis of EGVB [71.0% (495/697) VS 79.9% (111/139), χ2=4.11, P=0.033] and secondary prophylaxis of EGVB [41.6% (290/697) VS 27.3% (38/139), χ2=9.31, P=0.002]. A total of 78.2% (654/836) hospitals preferred endoscopic therapies treating acute EGVB, and endoscopic therapy was more likely to be the first choice for treating acute EGVB in tertiary hospitals (82.6%, 576/697) than secondary hospitals [56.1% (78/139), χ2=46.33, P<0.001]. The optimal timing was usually within 12 hours (48.5%, 317/654) and 12-24 hours (36.9%, 241/654) after the bleeding. Regarding the management of gastroesophageal varices type 2 and isolated gastric varices type 1, most hospitals used cyanoacrylate injection in combination with sclerotherapy [48.2% (403/836) and 29.9% (250/836), respectively], but substantial proportions of hospitals preferred clip-assisted therapies [12.4% (104/836) and 26.4% (221/836), respectively]. Improving the skills of endoscopic doctors (84.2%, 704/836), and enhancing the precision of pre-procedure evaluation and quality of multidisciplinary team (78.9%, 660/836) were considered urgent needs in the development of endoscopic treatment. Conclusion:A variety of endoscopic treatments for gastroesophageal varices in portal hypertension are implemented nationwide. Participant hospitals are active to perform emergent endoscopy for acute EGVB, but are inadequate in following recommendations regarding primary and secondary prophylaxis of EGVB. Moreover, the selection of endoscopic procedures for gastric varices differs greatly among hospitals.