1.Construction and application of a quality control and improvement system for metabolic and bariatric surgery in Beijing
Peirong TIAN ; Mengyi LI ; Jingli LIU ; Rixing BAI ; Jingtao BI ; Guanglong DONG ; Yanmin DU ; Jiagang HAN ; Wei HAN ; Yong JIANG ; Yuanxin LI ; Zhifei LI ; Hongwei LIN ; Diangang LIU ; Yang LIU ; Fanqiang MENG ; Runhong NI ; Jinghai SONG ; Qiang XU ; Wenmao YAN ; Nengwei ZHANG ; Chaohui ZHONG ; Peng ZHANG ; Zhongtao ZHANG
Chinese Journal of Surgery 2025;63(7):624-629
Objective:To establish and assess the quality control and improvement system for metabolic and bariatric surgery in Beijing.Methods:Based on relevant documents from the National Health Commission and the Beijing Municipal Health Commission,and referencing the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) by the American Society for Metabolic and Bariatric Surgery,a quality control system was developed under the Beijing Quality Control and Improvement Center of Metabolic and Bariatric Surgery. The system incorporated on-site evaluations,data registration,and specialized training. From May to December 2023,on-site assessments were conducted at 21 hospitals in Beijing performing bariatric surgery,evaluating personnel qualifications,infrastructure,clinical workflows,and postoperative follow-up. A quality control database was created to collect real-time surgical data,and training was provided for data entry and professional skills. Assessment results were classified as excellent,qualified,or needing improvement,with rectification suggestions offered and follow-up visits conducted to track progress.Results:All 21 hospitals achieved a 100% compliance rate for surgical indications, 16 (76.2%) met standardized surgical operation criteria,and 14 (66.7%) had standardized postoperative management. However,only 5 (23.8%) achieved a 12-month postoperative follow-up rate of ≥60%,and 4 (19.1%) had established specialized databases. Key challenges included insufficient specialized staffing (19.1%), lack of multidisciplinary collaboration (47.6%), inadequate equipment (57.1%), and low follow-up rates (57.1%). The database collected data from over 2 000 patients across 111 fields. After rectification, specialized database coverage rose to 61.9% (13 hospitals). Multi-level training programs developed backbone physicians and specialized nurses,significantly addressing the shortage of specialized personnel.Conclusion:The quality control system established in this study,through the integration of on-site evaluation,data registration,and specialized training,effectively enhances the standardization of surgical practices and data management capabilities.
2.The early clinical outcome of ACDF under a cervical soft endoscopic minimally invasive system in the treatment of two-segment cervical myelopathy
Qinghao ZHAO ; Yuanhan LIU ; Rongzhen LIN ; Zhiyang ZHENG ; Zezheng LIU ; Xinying ZHOU ; Chaohui FAN ; Qingchu LI
Chinese Journal of Orthopaedics 2025;45(1):37-43
Objective:To investigate the early clinical outcomes of anterior cervical discectomy and fusion (ACDF) in the treatment of two-segment cervical spondylotic myelopathy (CSM) using a cervical soft endoscopic minimally invasive system.Methods:A retrospective follow-up study was conducted on the medical records of 23 patients with two-segment cervical myelopathy who underwent ACDF using a soft endoscopic cervical spine minimally invasive system at the Third Affiliated Hospital of Southern Medical University between October 2022 and December 2023. The cohort included 15 males and 8 females, aged 37-79 years (58.52±11.77 years). The affected cervical segments included: C 3, 4 and C 4, 5 in 2 cases; C 3, 4 and C 5, 6 in 3 cases; C 4, 5 and C 5, 6 in 10 cases; C 5, 6 and C 6, 7 in 7 cases; and C 4, 5 and C 6, 7 in 1 case. Clinical outcomes were evaluated based on the Japanese Orthopaedic Association (JOA) scores and visual analog scale (VAS) for neck and shoulder pain, assessed preoperatively and at 1 week, 1 month, and 3 months postoperatively. Additional data recorded included incision length, intraoperative blood loss, operative time, postoperative complications, and the presence of prevertebral soft tissue edema. The improvement rate of JOA scores at the final follow-up was also calculated. Results:All patients successfully underwent surgery and completed follow-up, with follow-up durations ranging from 3 to 6 months (4.01±0.98 months). The mean operative time was 80.09±22.66 min (range: 53-127 min), and the mean incision length was 3.25±0.32 cm (range: 3-4 cm). Estimated blood loss ranged from 10 to 100 ml, with a mean of 34.78±24.1 ml. Postoperative drainage ranged from 0 to 80 ml (mean: 23.13±26.1 ml), and postoperative hospitalization durations ranged from 4 to 12 days (6.83±2.59 days). JOA scores improved significantly from a preoperative median of 9.00(8.00, 10.00) to 12.00(11.00, 14.00) at 1 week, 13.00(12.00, 14.00) at 1 month, and 15.00(15.00, 16.00) at 3 months postoperatively (χ 2=220.492, P<0.001). VAS scores for neck and shoulder pain also improved significantly from a preoperative median of 5.00(4.00, 6.00) to 3.00(2.00, 3.00) at 1 week, 2.00(2.00, 3.00) at 1 month, and 2.00(1.00, 2.00) at 3 months postoperatively (χ 2=170.869, P<0.001). No postoperative complications such as dysphagia, hoarseness, nerve injury, cerebrospinal fluid leakage, or intraspinal hematoma were observed. Imaging revealed no significant prevertebral soft tissue edema. At the final follow-up, the improvement rate of JOA scores resulted in 14 cases rated as excellent and 9 as good. Conclusions:ACDF using a cervical soft endoscopic minimally invasive system demonstrates satisfactory clinical outcomes for the treatment of two-segment CSM. This technique reduces the incidence of common complications associated with both open and traditional endoscopic surgeries.
3.Molecular epidemiological characteristics and risk factors analysis of Carbapenem-resistant Enterobacterales intestines colonization of neonates in Shenzhen region
Hongmei YANG ; Ke CAO ; Zhile XIONG ; Xiaochun LIU ; Kaiyue YANG ; Yunxing HE ; Shaoxiang LIN ; Jiahe ZOU ; Shuyan LIU ; Tongyan DING ; Lingfan YIN ; Zhixiang LI ; Chaohui DUAN ; Zhenwen ZHOU
Chinese Journal of Preventive Medicine 2025;59(7):1022-1030
Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.
4.A novel interlocking intramedullary nail for type AO 32-A3 femoral shaft fractures: a finite element analysis
Peisheng CHEN ; Chaohui LIN ; Fengfei LIN ; Bin CHEN ; Dongze LIN ; Ke ZHENG
Chinese Journal of Orthopaedic Trauma 2025;27(3):228-233
Objective:To compare the biomechanical stability of a novel interlocking intramedullary nail (nIMN) with that of a traditional interlocking intramedullary nail (tIMN) in the treatment of type AO 32-A3 femoral shaft fractures using a finite element analysis.Methods:A healthy adult male volunteer, aged 30 years old and weighing 70 kg, was selected for collection of his CT scan data of the femur. A three-dimensional finite element model of the femur was established using software Mimics 17.0 and Geomagic Studio. After femoral shaft fractures of AO/OTA types 32-A3a, 32-A3b, and 32-A3c were simulated, nIMN and tIMN were assembled respectively. After boundary conditions and material properties of the models were set based on reference literature, 4 load states were simulated: vertical standing, slow walking, fast walking, and descending stairs. The displacements and stress distribution at the femoral fracture ends under the same conditions were compared between nIMN and tIMN schemes of fixation. The stabilities of each fracture model at different fixation schemes and load states were analyzed.Results:In the 4 load states simulated, the displacements of the fracture ends averaged 0.129 mm, and the maximum stresses 111.00 MPa. The smallest displacement and maximum stress (0.014 mm and 29.48 MPa) were found in the vertical standing in the femoral shaft fracture of type 32-A3c fixed with nIMN. The largest displacement and maximum stress (0.325 mm and 242.98 MPa) were found in descending stairs in the femoral shaft fracture of type 32-A3a fixed with tIMN. In femoral shaft fractures of types 32-A3a, 32-A3b, and 32-A3c, regardless of tIMN or nIMN fixation, the displacement and maximum stress increased with the load, with the femoral shaft fracture of type 32-A3a being particularly evident. nIMN fixation resulted in lower displacements and maximum stresses in AO/OTA types 32-A3a, 32-A3b, and 32-A3c than tIMN fixation. Taking descending stairs as an example, the overall maximum stress occurred on the proximal part of the femur and the surrounding area of Adams'arc, with the maximum stress fluctuating between 86.62 and 242.98 MPa. The maximum stress at the fracture end fluctuated between 0.44 and 56.49 MPa. The stress mainly concentrated on the medial part, and decreased from type 32-A3a to type 32-A3b to type 32-A3c.Conclusion:In type AO 32-A3 femoral shaft fractures, nIMN leads to a smaller fracture end displacement and a lower maximum stress than tIMN, indicating better rotational stability.
5.The impact of sliding distance of the femoral neck system on the curative efficacy of displaced femoral neck fractures: a retrospective cohort study
Xiaole JIANG ; Dongze LIN ; Yixin HUANG ; Ke ZHENG ; Jiajie LIU ; Chaohui LIN ; Peisheng CHEN ; Fengfei LIN
Chinese Journal of Orthopaedic Trauma 2025;27(9):758-766
Objective:To investigate the impact of sliding distance of the fmoral neck system (FNS) on the curative efficacy of displaced femoral neck fractures.Methods:A retrospective study was conducted to analyze the clinical data of the 179 patients with displaced femoral neck fracture who had been treated by FNS fixation at Department of Orthopaedics, The Second General Hospital of Fuzhou between September 2019 and September 2023. Based on the FNS sliding distance measured on X-ray films on the day after surgery or one day after surgery, the patients were assigned into 2 groups: a short sliding distance group [sliding distance ≤5 mm, n=55; 35 males, 20 females; median age: 50.0 (34.0, 59.0) years; body mass index (BMI): (24.0±2.4) kg/m 2] and a long sliding distance group [5 mm
6.Construction and evaluation of a diagnostic model for female stress urinary incontinence based on the mor-phology and elasticity of the levator ani muscle by transperineal three-dimensional ultrasound combined with shear wave elastography
Erfang GUO ; Lei FENG ; Chaohui SHI ; Ning LI ; Weiqun LIN ; Shuhua ZHANG
The Journal of Practical Medicine 2025;41(8):1224-1231
Objective To investigate the relationship between the morphology and elasticity of the levator ani muscle(LAM)and stress urinary incontinence(SUI),and to develop a multimodal diagnostic model for SUI based on LAM morphology and elasticity parameters,while evaluating the diagnostic performance of this model.Methods From September 2020 to September 2022,147 female patients with SUI from the Affiliated Hospital of North China University of Science and Technology were enrolled as the SUI group(case group),while 144 women without SUI during the same period were selected as the non-SUI group(control group).Transperineal ultrasonography was conducted to measure the anteroposterior diameter(LH-A1)and transverse diameter(LH-D1)of the levator hiatus at rest,the resting area of the levator hiatus(LA1),as well as the anteroposterior diameter(LH-A2),transverse diameter(LH-D2),and area(LA2)of the levator hiatus during the maximum Valsalva maneuver.Addi-tionally,ultrasonography was used to observe LAM injury(LA-MI)during pelvic muscle contraction.Shear wave elastography(SWE)was also performed transperineally to record the elastic modulus values of the puborectalis muscle at rest(E1)and during pelvic muscle contraction(E3).The differences in ultrasound parameters between the two groups were compared,and a logistic regression model was constructed for multivariate analysis to establish a diagnostic model for SUI.The goodness of fit of the logistic regression model was assessed using the Hosmer-Lemeshow test.The diagnostic performance of individual indicators and the diagnostic model for SUI was evaluated using the receiver operating characteristic(ROC)curve.Finally,the clinical utility of the model was assessed using decision curve analysis.Results There were statistically significant differences in age,BMI,LH-A1,LH-D1,LA1,LH-A2,LH-D2,LA2,LA-MI,E1,and E3 between the two groups(P<0.05).Multivariate logistic regression analysis revealed that age,BMI,LH-A1,LA2,LA-MI,E1,and E3 were significantly associated with SUI(P<0.05).Based on these findings,a diagnostic model for SUI was established:PRESUI=0.261×age+0.904×BMI-4.300×LH-A1+1.166×LA2-2.815×LA-MI+0.587×E1-0.631×E3-1.258.The model demon-strated excellent goodness-of-fit(P=0.983).The ROC curve analysis indicated that age,BMI,LH-A1,LA2,LA-MI,E1,and E3 all exhibited diagnostic efficacy for SUI(AUC>0.500,P<0.05).Notably,the AUC of the constructed diagnostic model for SUI was 0.996(95%CI:0.992~1.000),suggesting that the diagnostic accuracy of the model surpassed that of individual indicators.When the cut-off value of the diagnostic model was set at 0.437,the sensitivity reached 98.0%,and the specificity was 97.2%.Furthermore,the decision curve analysis demon-strated that the diagnostic model provided substantial net clinical benefit within the threshold probability range of 0.1 to 1.0.Conclusions The morphology and elasticity of the LAM are significantly altered in women with SUI.The SWE technique demonstrates potential application value for quantitatively assessing the elasticity of the LAM.Furthermore,the diagnostic model constructed based on age,BMI,LH-A1,LA2,LA-MI,E1,and E3 exhibits high clinical application value.
7.The early clinical outcome of ACDF under a cervical soft endoscopic minimally invasive system in the treatment of two-segment cervical myelopathy
Qinghao ZHAO ; Yuanhan LIU ; Rongzhen LIN ; Zhiyang ZHENG ; Zezheng LIU ; Xinying ZHOU ; Chaohui FAN ; Qingchu LI
Chinese Journal of Orthopaedics 2025;45(1):37-43
Objective:To investigate the early clinical outcomes of anterior cervical discectomy and fusion (ACDF) in the treatment of two-segment cervical spondylotic myelopathy (CSM) using a cervical soft endoscopic minimally invasive system.Methods:A retrospective follow-up study was conducted on the medical records of 23 patients with two-segment cervical myelopathy who underwent ACDF using a soft endoscopic cervical spine minimally invasive system at the Third Affiliated Hospital of Southern Medical University between October 2022 and December 2023. The cohort included 15 males and 8 females, aged 37-79 years (58.52±11.77 years). The affected cervical segments included: C 3, 4 and C 4, 5 in 2 cases; C 3, 4 and C 5, 6 in 3 cases; C 4, 5 and C 5, 6 in 10 cases; C 5, 6 and C 6, 7 in 7 cases; and C 4, 5 and C 6, 7 in 1 case. Clinical outcomes were evaluated based on the Japanese Orthopaedic Association (JOA) scores and visual analog scale (VAS) for neck and shoulder pain, assessed preoperatively and at 1 week, 1 month, and 3 months postoperatively. Additional data recorded included incision length, intraoperative blood loss, operative time, postoperative complications, and the presence of prevertebral soft tissue edema. The improvement rate of JOA scores at the final follow-up was also calculated. Results:All patients successfully underwent surgery and completed follow-up, with follow-up durations ranging from 3 to 6 months (4.01±0.98 months). The mean operative time was 80.09±22.66 min (range: 53-127 min), and the mean incision length was 3.25±0.32 cm (range: 3-4 cm). Estimated blood loss ranged from 10 to 100 ml, with a mean of 34.78±24.1 ml. Postoperative drainage ranged from 0 to 80 ml (mean: 23.13±26.1 ml), and postoperative hospitalization durations ranged from 4 to 12 days (6.83±2.59 days). JOA scores improved significantly from a preoperative median of 9.00(8.00, 10.00) to 12.00(11.00, 14.00) at 1 week, 13.00(12.00, 14.00) at 1 month, and 15.00(15.00, 16.00) at 3 months postoperatively (χ 2=220.492, P<0.001). VAS scores for neck and shoulder pain also improved significantly from a preoperative median of 5.00(4.00, 6.00) to 3.00(2.00, 3.00) at 1 week, 2.00(2.00, 3.00) at 1 month, and 2.00(1.00, 2.00) at 3 months postoperatively (χ 2=170.869, P<0.001). No postoperative complications such as dysphagia, hoarseness, nerve injury, cerebrospinal fluid leakage, or intraspinal hematoma were observed. Imaging revealed no significant prevertebral soft tissue edema. At the final follow-up, the improvement rate of JOA scores resulted in 14 cases rated as excellent and 9 as good. Conclusions:ACDF using a cervical soft endoscopic minimally invasive system demonstrates satisfactory clinical outcomes for the treatment of two-segment CSM. This technique reduces the incidence of common complications associated with both open and traditional endoscopic surgeries.
8.Molecular epidemiological characteristics and risk factors analysis of Carbapenem-resistant Enterobacterales intestines colonization of neonates in Shenzhen region
Hongmei YANG ; Ke CAO ; Zhile XIONG ; Xiaochun LIU ; Kaiyue YANG ; Yunxing HE ; Shaoxiang LIN ; Jiahe ZOU ; Shuyan LIU ; Tongyan DING ; Lingfan YIN ; Zhixiang LI ; Chaohui DUAN ; Zhenwen ZHOU
Chinese Journal of Preventive Medicine 2025;59(7):1022-1030
Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.
9.Construction and evaluation of a diagnostic model for female stress urinary incontinence based on the mor-phology and elasticity of the levator ani muscle by transperineal three-dimensional ultrasound combined with shear wave elastography
Erfang GUO ; Lei FENG ; Chaohui SHI ; Ning LI ; Weiqun LIN ; Shuhua ZHANG
The Journal of Practical Medicine 2025;41(8):1224-1231
Objective To investigate the relationship between the morphology and elasticity of the levator ani muscle(LAM)and stress urinary incontinence(SUI),and to develop a multimodal diagnostic model for SUI based on LAM morphology and elasticity parameters,while evaluating the diagnostic performance of this model.Methods From September 2020 to September 2022,147 female patients with SUI from the Affiliated Hospital of North China University of Science and Technology were enrolled as the SUI group(case group),while 144 women without SUI during the same period were selected as the non-SUI group(control group).Transperineal ultrasonography was conducted to measure the anteroposterior diameter(LH-A1)and transverse diameter(LH-D1)of the levator hiatus at rest,the resting area of the levator hiatus(LA1),as well as the anteroposterior diameter(LH-A2),transverse diameter(LH-D2),and area(LA2)of the levator hiatus during the maximum Valsalva maneuver.Addi-tionally,ultrasonography was used to observe LAM injury(LA-MI)during pelvic muscle contraction.Shear wave elastography(SWE)was also performed transperineally to record the elastic modulus values of the puborectalis muscle at rest(E1)and during pelvic muscle contraction(E3).The differences in ultrasound parameters between the two groups were compared,and a logistic regression model was constructed for multivariate analysis to establish a diagnostic model for SUI.The goodness of fit of the logistic regression model was assessed using the Hosmer-Lemeshow test.The diagnostic performance of individual indicators and the diagnostic model for SUI was evaluated using the receiver operating characteristic(ROC)curve.Finally,the clinical utility of the model was assessed using decision curve analysis.Results There were statistically significant differences in age,BMI,LH-A1,LH-D1,LA1,LH-A2,LH-D2,LA2,LA-MI,E1,and E3 between the two groups(P<0.05).Multivariate logistic regression analysis revealed that age,BMI,LH-A1,LA2,LA-MI,E1,and E3 were significantly associated with SUI(P<0.05).Based on these findings,a diagnostic model for SUI was established:PRESUI=0.261×age+0.904×BMI-4.300×LH-A1+1.166×LA2-2.815×LA-MI+0.587×E1-0.631×E3-1.258.The model demon-strated excellent goodness-of-fit(P=0.983).The ROC curve analysis indicated that age,BMI,LH-A1,LA2,LA-MI,E1,and E3 all exhibited diagnostic efficacy for SUI(AUC>0.500,P<0.05).Notably,the AUC of the constructed diagnostic model for SUI was 0.996(95%CI:0.992~1.000),suggesting that the diagnostic accuracy of the model surpassed that of individual indicators.When the cut-off value of the diagnostic model was set at 0.437,the sensitivity reached 98.0%,and the specificity was 97.2%.Furthermore,the decision curve analysis demon-strated that the diagnostic model provided substantial net clinical benefit within the threshold probability range of 0.1 to 1.0.Conclusions The morphology and elasticity of the LAM are significantly altered in women with SUI.The SWE technique demonstrates potential application value for quantitatively assessing the elasticity of the LAM.Furthermore,the diagnostic model constructed based on age,BMI,LH-A1,LA2,LA-MI,E1,and E3 exhibits high clinical application value.
10.A novel interlocking intramedullary nail for type AO 32-A3 femoral shaft fractures: a finite element analysis
Peisheng CHEN ; Chaohui LIN ; Fengfei LIN ; Bin CHEN ; Dongze LIN ; Ke ZHENG
Chinese Journal of Orthopaedic Trauma 2025;27(3):228-233
Objective:To compare the biomechanical stability of a novel interlocking intramedullary nail (nIMN) with that of a traditional interlocking intramedullary nail (tIMN) in the treatment of type AO 32-A3 femoral shaft fractures using a finite element analysis.Methods:A healthy adult male volunteer, aged 30 years old and weighing 70 kg, was selected for collection of his CT scan data of the femur. A three-dimensional finite element model of the femur was established using software Mimics 17.0 and Geomagic Studio. After femoral shaft fractures of AO/OTA types 32-A3a, 32-A3b, and 32-A3c were simulated, nIMN and tIMN were assembled respectively. After boundary conditions and material properties of the models were set based on reference literature, 4 load states were simulated: vertical standing, slow walking, fast walking, and descending stairs. The displacements and stress distribution at the femoral fracture ends under the same conditions were compared between nIMN and tIMN schemes of fixation. The stabilities of each fracture model at different fixation schemes and load states were analyzed.Results:In the 4 load states simulated, the displacements of the fracture ends averaged 0.129 mm, and the maximum stresses 111.00 MPa. The smallest displacement and maximum stress (0.014 mm and 29.48 MPa) were found in the vertical standing in the femoral shaft fracture of type 32-A3c fixed with nIMN. The largest displacement and maximum stress (0.325 mm and 242.98 MPa) were found in descending stairs in the femoral shaft fracture of type 32-A3a fixed with tIMN. In femoral shaft fractures of types 32-A3a, 32-A3b, and 32-A3c, regardless of tIMN or nIMN fixation, the displacement and maximum stress increased with the load, with the femoral shaft fracture of type 32-A3a being particularly evident. nIMN fixation resulted in lower displacements and maximum stresses in AO/OTA types 32-A3a, 32-A3b, and 32-A3c than tIMN fixation. Taking descending stairs as an example, the overall maximum stress occurred on the proximal part of the femur and the surrounding area of Adams'arc, with the maximum stress fluctuating between 86.62 and 242.98 MPa. The maximum stress at the fracture end fluctuated between 0.44 and 56.49 MPa. The stress mainly concentrated on the medial part, and decreased from type 32-A3a to type 32-A3b to type 32-A3c.Conclusion:In type AO 32-A3 femoral shaft fractures, nIMN leads to a smaller fracture end displacement and a lower maximum stress than tIMN, indicating better rotational stability.

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