Thoracolumbar spine fracture often leads to severe pain, functional impairments, and neurological deficits, for which open reduction and internal fixation can effectively restore the spinal structural stability. Open decompression and reduction with internal fixation can help relieve spinal cord compression and improve spinal function in cases of concomitant cord injury. Although spinal stability can be restored through surgery, patients often face chronic pain and functional impairments postoperatively. A postoperative rehabilitation program is critical in optimizing therapeutic outcomes, reducing complications, and minimizing the risk of secondary injuries. However, current rehabilitation methods, such as physical therapy, functional training, and pain management, are confronted with problems in clinical practice, including significant variation in efficacy, poor patient adherence, and prolonged rehabilitation period. There is an urgent need for a unified rehabilitation strategy to address these problems. To this end, the Spinal Trauma Group of the Orthopedic Physicians Branch of the Chinese Medical Association and the Spine Health Professional Committee of the Chinese Human Health Technology Promotion Association organized experts from relevant fields to formulate Evidence-based guidelines for rehabilitation treatment after internal fixation of thoracolumbar spine fracture in adults ( version 2025) by integrating evidences from clinical researches and advanced rehabilitation concepts at home and abroad. A total number of 14 recommendations concerning the rehabilitation treatment with multimodal analgesia, psychological intervention, deep vein thrombosis prevention, core muscle and extremity exercise, appropriate use of braces, early weight-bearing, device-aided rehabilitation exercise, neuroregulatory therapy, rehabilitation team were put forward, aiming to standardize the post-operative rehabilitation process following internal fixation, promote the functional recovery, and enhance patients′ quality of life.

Objective:To compare the efficacy of closed reduction and internal fixation combined with percutaneous kyphoplasty (PKP) and non-operative treatment for intertrochanteric fracture combined with osteoporotic vertebral compression fracture (OVCF) in the elderly.Methods:A retrospective cohort study was conducted to analyze the clinical data of 59 patients with intertrochanteric fracture combined with OVCF admitted to Tianjin Hospital from June 2020 to June 2023, including 16 males and 43 females, aged 66-91 years [(80.2±6.8)years]. The injured vertebral segments included T 10 in 3 patients, T 11 in 9, T 12 in 18, L 1 in 17, L 2 in 8, and L 3 in 4. According to the Genant semi-quantitative classification of vertebral fracture, 42 patients were scaled into grade 1 and 17 into grade 2. Based on the AO classification of intertrochanteric fracture, 33 patients were classified as type A1, 21 type A2, and 5 type A3. All the patients underwent closed reduction and internal fixation for intertrochanteric fractures, among whom 26 patients received PKP after the internal fixation of OVCF (PKP group) and 33 patients received non-surgical treatment after the internal fixation of OVCF (non-surgical group). The healing of the hip incision at 2 weeks after internal fixation and the healing of intertrochanteric fractures at 6 months after surgery were observed in both groups. The visual analogue scale (VAS) for low back pain was compared between the two groups before PKP, immediately after PKP, at 3 months after PKP, and at the last follow-up. The Oswestry disability index (ODI), anterior vertebral height ratio, and Cobb angle of the injured vertebrae were compared between the two groups before PKP, at 3 months after PKP, and at the last follow-up. The Harris hip function score was compared between the two groups at 3 months after internal fixation and at the last follow-up. Cement leakage was observed. The incidence of deep vein thrombosis (DVT) in the lower extremities after internal fixation were compared between the two groups. Results:All the patients were followed up for 10-46 months [(25.5±9.9)months]. The hip incisions of both groups all healed by first intention at 2 weeks after internal fixation, and the intertrochanteric fracture in both groups had bony union at 6 months after surgery. There were no significant differences between the two groups in VAS or ODI before PKP ( P>0.05). Immediately after PKP, at 3 months after PKP, and at the last follow-up, the VAS scores for low back pain were (2.6±0.6)points, (2.4±0.9)points, and (1.5±0.5)points in the PKP group, which were lower than those in the non-surgical group [(8.2±0.8)points, (3.7±1.2)points, and (3.3±0.6)points] ( P<0.01). At 3 months after PKP and at the last follow-up, the ODI values were (21.4±6.9)% and (16.2±6.3)% in the PKP group, which were lower than (38.6±11.6)% and (32.7±12.0)% in the non-surgical group ( P<0.01). The VAS for low back pain and ODI in both groups were gradually improved at each time point after PKP compared with those before PKP ( P<0.05 or 0.01). There were no significant differences in the anterior vertebral height ratio or Cobb angle of the injured vertebrae in the two groups before PKP ( P>0.05). At 3 months after PKP and at the last follow-up, the anterior vertebral height ratio was (79.8±9.6)% and (79.3±9.4)% in the PKP group, which were higher than (73.4±9.3)% and (62.0±10.4)% in the non-surgical group ( P<0.05 or 0.01); the values of the Cobb angle of the injured vertebrae were (12.6±3.6)° and (12.0±3.3)°in the PKP group, which were lower than (15.5±2.6)° and (20.4±4.9)° in the non-surgical group ( P<0.01). There were no significant differences in the anterior vertebral height ratio and Cobb angle of the injured vertebrae in the PKP group before PKP and at each time point after PKP ( P>0.05) while in the non-surgical group, the anterior vertebral height ratio at each time point after PKP was lower than that before PKP and the Cobb angle of the injured vertebrae was increased compared with that before PKP ( P<0.01). At 3 months after internal fixation and at the last follow-up, the Harris hip function scores in the PKP group were (76.4±3.4)points and (87.7±4.5)points, which were higher than (57.0±6.8)points and (76.3±8.9)points in the non-surgical group ( P<0.01). The Harris hip function scores in both groups were improved at the last follow-up, compared with those at 3 months after internal fixation. Five patients had cement leakage in the PKP group, all of which were lateral leakage.There was no occurrence of radiating pain in the lower extremities. The incidence of DVT at 1 month after internal fixation was 19.2% (5/26) in the PKP group, which was lower than 57.6% (19/33) in the non-surgical group ( P<0.01). Conclusion:Compared with non-operative treatment after the closed reduction and internal fixation, PKP after internal fixation can significantly relieve low back pain in the early stage, improve the functional restoration of the vertebral column, maintain vertebral height, prevent kyphosis, promote the recovery of the hip joint function, and reduce the occurrence of DVT in the lower extremities in the treatment of intertrochanteric fracture combined with OVCF.

Acute symptomatic osteoporotic thoracolumbar compression fracture (ASOTLF) can lead to chronic low back pain, kyphosis deformity, pulmonary dysfunction, loss of mobility, and even life-threatening complications. Vertebral augmentation is currently the mainstream treatment method for this condition. In 2019, the Editorial Board of Chinese Journal of Trauma and the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association collaboratively led the development of Clinical guideline for vertebral augmentation for acute symptomatic osteoporotic thoracolumbar compression fractures. Six years later, with advances in clinical diagnosis and treatment techniques as well as accumulating evidence in related fields, the 2019 guideline requires updating. To this end, the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association, the Spinal Health Professional Committee of China Human Health Science and Technology Promotion Association, and the Minimally Invasive Orthopedics Professional Committee of Shaanxi Medical Doctor Association have organized experts in the field to develop the Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures ( version 2025) , based on the latest evidence-based medical researches. This guideline incorporates 3 recommendations retained from the 2019 version with updated strength of evidence, along with 12 new recommendations. It provides recommendations from six aspects of diagnosis, pain management, treatment option selection, prevention of postoperative complications, anti-osteoporosis therapy, and postoperative rehabilitation, aiming to provide a reference for standard treatment of vertebral augmentation for ASOTLF in hospitals at all levels.

Objective:To explore the correlation between metabolic syndrome (MS), serum high-sensitivity C-reactive protein (hs-CRP) levels, their combination and the risk of digestive system malignancies.Methods:A prospective cohort study was conducted in the participants from the Kailuan cohort who took health examination in July 2006. Anthropometric parameters, epidemiological information, and laboratory test results were collected. Incidence and mortality of digestive system malignant tumors were collected through biennial health examinations and questionnaires. The follow-up period ended on December 31, 2021.According to MS status and hs-CRP levels (hs-CRP≤3 or >3 mg/L), the cohort was divided into 4 groups, induding MS -hs-CRP -, MS -hs-CRP +, MS + hs-CRP -, and MS + hs-CRP + group. Chi-squared test, one analysis of variance, and the Kruskal-Wallis H test were used for inter-group comparison among groups. Kaplan-Meier method was used to calculate the cumulative incidence of digestive system malignant tumors, and log-rank test was performed to compare the cumulative incidence among groups. Multivariable Cox proportional hazards regression models were used to evaluate the effects of MS and hs-CRP levels on the overall risk of digestive system malignant tumors, as well as the effects of their combination on the risk of digestive system malignant tumors of different site, and relevant confounding factors were adjusted.A sensitivity analysis was conducted by excluding individuals diagnosed with digestive system malignancies within one year of follow-up, as well as those taking antihypertensive, antidiabetic, or lipid-lowering medications. Results:A total of 92 916 participants were included in this study. Among them, 57 933 cases were in the MS -hs-CRP - group, 10 949 cases in the MS -hs-CRP + group, 18 412 cases in the MS + hs-CRP - group, and 5 622 cases in the MS + hs-CRP + group.The median follow-up period was 15.01 years (14.66 to 15.20 years). By the end of follow-up, these were 1 992 cases of new-onset digestive system malignant tumors. The cumulative incidence rates of digestive system malignant tumors of MS -hs-CRP -, MS -hs-CRP +, MS + hs-CRP -, and MS + hs-CRP + groups were 2.0%(1 164/57 933), 2.3%(249/10 949), 2.4%(440/18 412), and 2.5%(139/5 622), respectively. The difference in the cumulative incidence among the 4 groups was statistically significant ( χ2=14.09, P=0.003).The results of multivariate Cox analysis showed that, after hs-CRP level and other confounding factors were adjusted, the risk of developing digestive system malignant tumors in participants with MS was 21.4% higher than that in those without MS ( HR=1.214 (95% confidence interval (95% CI): 1.086 to 1.340), P<0.001). After MS status and other confounding factors were adjusted, the risk of developing digestive system malignant tumors in participants with high hs-CRP level (>3 mg/L) was 17.2% higher than those with low hs-CRP level (≤3 mg/L) ( HR=1.172 (95% CI: 1.042 to 1.303), P=0.008). After relevant confounding factors were adjusted, the risks of developing digestive system malignant tumors in the MS -hs-CRP +, MS + hs-CRP -, and MS + hs-CRP + groups increased by 17.2%, 21.4%, and 35.9%, respectively, as compared with that of the MS -hs-CRP - group ( HR=1.172 (95% CI: 1.017 to 1.399), P=0.028; HR=1.214 (95% CI: 1.074 to 1.356), P=0.002; HR=1.359 (95% CI: 1.135 to 1.635), P=0.001). Among the 4 groups, the overall risk of developing digestive system malignant tumors of MS + hs-CRP + group was the highest. After relevant confounding factors were adjusted, the risks of colorectal cancer, liver cancer, and pancreatic cancer of the MS + hs-CRP + group increased by 46.2%, 35.7%, and 88.3%, respectively, as compared with those of the MS -hs-CRP - group ( HR=1.462 (95% CI: 1.088 to 1.956), HR=1.357 (95% CI: 1.132 to 2.089), HR=1.883 (95% CI: 1.052 to 3.342)), suggesting that MS combined with high hs-CRP was a significant risk factor for increased incidences of colorectal cancer, liver cancer, and pancreatic cancer ( P=0.012, 0.016 and 0.033). After participants diagnosed with new digestive system malignancies within one year of follow-up and those taking antihypertensive, antidiabetic, or lipid-lowering medications (108 cases, 10 680 cases, 2 344 cases, 906 cases) were excluded, the results of sensitivity analysis indicated the increased risk of digestive system malignant tumors in the MS -hs-CRP +, MS + hs-CRP -, and MS + hs-CRP + groups were 12.1%, 21.4%, 28.7%; 18.2%, 21.4%, 24.8%; 16.4%, 21.4%, 32.2%; 17.3%, 20.4%, 35.8%. Among the 3 groups, the increased risk of developing digestive system malignant tumors of MS + hs-CRP + group was the highest. Conclusion:MS and hs-CRP >3 mg/L are both independent risk factors for developing digestive system malignant tumors, and their combination further increases the risk of developing digestive system malignant tumors.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To explore the degree of change in anteversion angle and related risk factors after intramedullary nail fixation of intertrochanteric femur fracture in the elderly.Methods:The data of 256 elderly patients who underwent intramedullary nail fixation for intertrochanteric fractures of the femur at Tianjin Hospital of Tianjin University from March 2020 to March 2023 were selected, including 114 males and 142 females, with an age of 75.40±10.69 years (range, 65-94 years). The degree of change in the anteversion angle of the affected hip before and after the surgery was measured by CT scan of the hip, the Receiver Operating Characteristic Curve (ROC) was plotted, the area under the ROC curve was analyzed, and the optimal degree of grouping was determined by calculating the Youden Index, then all the patients were divided into two groups. The correlation between various risk factors (age, sex, type of internal fixation, fracture AO type, quality of reduction, fracture medial cortical defect or not, cusp distance) and the change of anterior tilt angle was screened by univariate and multivariate logistic regression analyses.Results:All 256 patients were followed up for 20.7±2.1 months (range, 18-23 months). Anteversion on the healthy side was 12.68°±5.10° (range, 5°-28°); postoperative anteversion on the affected side was 15.04°±7.67° (range, 9°-36°). By comparing the difference in the anterior tilt angle between the affected side and the healthy side, it was found that the anterior tilt angle of 67 patients was completely restored to the healthy side level after the operation. The anteversion angle was enlarged in 131 cases, of which the mildly increased angle (1°-9°) was found in 106 cases, moderately increased (10°-15°) was found in 17 cases, and significantly increased (>15°) was found in 8 cases; 58 patients showed anteversion angle reduction, of which 45 cases were mildly reduced (1°-9°), 13 cases were moderately reduced (10°-14°). The area under the ROC curve for the patient's anteversion angle and its 95% CI were 0.714(0.559, 0.867), and the maximum value of its Youden Index was 0.221, which corresponded to the optimal critical angle of 4°. There was no statistically significant difference in age, gender, reduction quality or fracture AO classification between the group with an anteversion angle>4° and the group with an anteversion angle≤4° ( P>0.05). The types of internal fixation, medial cortical defect and insufficient tip apex distance (TAD) were included in the binary variable logistic regression analysis. The results showed that single-nail internal fixation [ OR=0.412, 95% CI(0.244, 0.695), P=0.007], medial cortical defect [ OR=0.471, 95% CI(0.279, 0.793), P=0.009] and TAD>25 mm [ OR=0.367, 95% CI(0.207, 0.651), P=0.003] are independent risk factors for changes in anteversion angle after intramedullary nail fixation of intertrochanteric femur fractures in elderly. Conclusion:Single-nail internal fixation, medial cortical defect and TAD >25 mm are independent risk factors for the change of anteversion angle after intramedullary nail internal fixation of intertrochanteric fractures in the elderly.