Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.

Objective:To explore the structural equation model to explore the levels of work-related musculoskeletal disorders (WMSDs) and various risk factors in the feet and ankle of China's occupational population, providing scientific basis for for preventing WMSDs in feet and ankles.Methods:Data of 73497 national occupational epidemiological cases were selected from June 2018 to December 2023 used the Chinese version of the Electronic Questionnaire on Musculoskeletal Disorders. The adverse ergonomic factors and their source classification standard and confirmatory factor analysis were used to investigate foot and ankle WMSDs and their related risk factors (including individual factors, work organization, work posture, work type, fatigue, etc.) in key occupational groups in China, and structural equation model hypothesis, fitting, verification, and path and intermediary effect analysis were carried out. The model fit evaluation indexes included Chi-square specific degrees of freedom ( χ2/ df), gauge fit index (NFI), Tucker Lewis index (TLI), goodness of Fit index (GFI), adjusted Goodness of Fit index (AGFI) and approximate root mean square error (RMSEA) . Results:A total of 73497 occupational workers were surveyed, with local muscle fatigue and WMSDs incidence rates in the feet and ankles being 17.17% and 12.06%, respectively. The fitting index of the adjusted structural equation model basically meets the standard (GFI=1, AGFI=1, RMESA=0.042, NFI=0.716, TLI=0.663). The top three factors affecting feet and ankle WMSDs are feet and ankle muscle fatigue, work type, and work organization, with standardized path coefficients of 0.221, 0.105, and 0.095, respectively. The top two factors affecting feet and ankle muscle fatigue are work organization and work type, with standardized path coefficients of 0.548 and 0.383, respectively. Feet and ankle muscle fatigue, work type, work organization, and work posture have a direct effect on feet and ankle WMSDs, with effect values of 0.221, 0.105, 0.095, and 0.077, respectively. The organization and type of work can also have indirect effects through feet and ankle muscle fatigue, with effect values of 0.121 and 0.084, respectively.Conclusion:Feet and ankle muscle fatigue has a direct impact on WMSDs, and plays a mediating role between ankle and ankle WMSDs caused by work organization and work type. Feet and ankle muscle fatigue is an important pathway leading to feet and ankle WMSDs. It is recommended that employers and managers detect job fatigue early and take corresponding prevention and intervention measures, which can play a key role in preventing feet and ankle WMSDs.

Objective:To compare the therapeutic effects of cannulated screws and Kirschner wires in the treatment of medial malleolar fractures of Salter-Harris types Ⅲ and Ⅳ in children.Methods:A retrospective study was conducted to analyze the data of 48 and 16 children who had been treated respectively at Department of Pediatric Orthopaedics, Fuzhou Second General Hospital, and Department of Pediatric Orthopaedics, Foshan Hospital of Traditional Chinese Medicine for medial malleolar fractures of Salter-Harris types Ⅲ and Ⅳ from June 2016 to June 2022. There were 32 males and 32 females with an age of 12 (10, 14) years; 31 left and 33 right sides were affected. By the Salter-Harris classification: type Ⅲ in 45 cases, and type Ⅳ in 19 cases. The patients were divided into 2 groups according to their internal fixation methods. Group A (44 cases) was subjected to internal fixation with cannulated screws and group B (20 cases) to internal fixation with Kirschner wires. At the last follow-up, anteroposterior and lateral X-ray films of their ankle joints were taken for imaging evaluation. Functional recovery of the affected limbs was evaluated based on the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scoring, and related complications were recorded.Results:The 2 groups were comparable because there were no significant differences in their preoperative general data except laterality ( P>0.05). All the patients were followed up for (37.3±21.5) months and achieved bony union. At the last follow-up, for groups A and B respectively, the distal lateral angle of the tibia was 89.0° (89.0°, 90.0°) and 89.0° (89.0°, 90.0°), the range of ankle motion was 73.5° (67.8°, 76.0°) and 70.0° (70.0°, 75.0°), and the good and excellent rate by the AOFAS ankle-hindfoot scoring was 97.7% (43/44) and 95.0% (19/20), showing no significant difference between the 2 groups ( P>0.05). There was a significant difference between the 2 groups in the incidence of premature physeal closure [36.4% (16/44) versus 65.0% (13/20)] ( P=0.033). Conclusions:In the treatment of medial malleolar fractures of Salter-Harris types Ⅲ and Ⅳ in children, internal fixation with both cannulated screws and Kirschner wires can lead to comparable efficacy in good functional recovery and imaging evaluation. However, fixation with cannulated screws may be more advantageous in reducing the risk of early closure of the epiphysis.

Objective:To explore the clinical features and surgical outcomes of greater trochanteric fractures of the femoral neck in children.Methods:A retrospective study was conducted to analyze the 5 children with greater trochanteric fracture of the femoral neck who had been treated at Department of Pediatric Orthopaedics, Fuzhou Second General Hospital from January 2011 to December 2020. There were 1 boy and 4 girls, with an age of (11.0±1.9) years. By the Delbet classification, all were type Ⅲ fractures. The time from injury to operation was (4.4±2.1) days. The children were treated with cannulated screws (1 case) or fixation with a pediatric hip plate (4 cases). The clinical features of such fractures were analyzed; the fracture union time and hip function and complications at the last follow-up were recorded.Results:The clinical features of greater trochanteric fractures of the femoral neck in children were: (1) involvement of 2 anatomic sites in a narrow region, (2) comminuted fractures, and (3) all Delbet type Ⅲ fractures. The follow-up time was (22.8±6.0) months. All the 5 children obtained bony union. The union time was (5.2±1.8) weeks for greater trochanteric fractures, and 8.0 (8.0,10.0) weeks for femoral neck fractures. Follow-up observed no necrosis of the femoral head, premature closure of the femoral head epiphysis, hip varus deformity, or length disparity between the lower limbs. Premature closure of the greater trochanteric epiphysis occurred in 2 children after surgery. According to the Ratliff scoring, the hip function was excellent in 3 cases and good in 2.Conclusions:Greater trochanteric fractures of the femoral neck in children are a special kind of proximal femoral comminuted fractures that affect 2 anatomic sites in a narrow region and belong all to Delbet type Ⅲ fractures. Open reduction and internal fixation with cannulated screws or a pediatric hip plate is a safe and effective treatment for such fractures.

The PCR-amplified severe fever with thrombocytopenia syndrome virus(SFTSV)Gn-DⅢ-Ⅲ gene was inserted into the pET-30a(+)prokaryotic expression vector to generate the re-combinant plasmid pET-SFTSV-Gn-D Ⅲ-Ⅲ.The plasmid was transformed into E.coli BL21(DE3)for Gn-DⅢ-m protein expression and the expression conditions were optimized.The Gn-DⅢ-Ⅲ protein purified with Ni-NTA column affinity chromatography was applied as the captured antigen to establish an indirect ELISA method for the detection of SFTSV antibody.The results demonstrated that the recombinant plasmid pET-SFTSV-Gn-D Ⅲ-Ⅲ was successfully constructed as identified by PCR and sequencing.The recombinant protein SFTSV Gn-D m-Ⅲ was soluble ex-pression in E.coli under the optimal induction conditions of 0.4 mmol/L IPTG at 25 ℃ for 4 h,and the protein purity was 91.77％after purification by Ni-NTA column.The optimal reaction con-ditions for the indirect ELISA of SFTSV antibody were as follows:coating antigen concentration(5 μg/mL),primary antibody(incubation at 37 ℃ for 1.5 h),and secondary antibody(diluted 1:10 000 and incubated at 37 ℃ for 1 h).The established method had no cross-reactivity with Rift Valley fever virus(RVFV),Ebola virus(EBOV),and tick-borne encephalitis virus(TBEV)posi-tive sera.The method had a high sensitivity,with P/N＞2.1 for SFTSV-positive sera diluted to 81920.Coefficients of variation for intra-and inter-batch reactions were less than 10％.Detection of four SFTSV-infected human clinical serum samples showed the serum samples from patients in re-mission were tested as positive(P/N＞2.1),while serum samples from patients with multiple or-gan failure were detected as negative(P/N＜2.1).The results indicated that the SFTSV Gn-D Ⅲ-Ⅲ protein was successfully expressed and purified,and it was used as the coating protein to estab-lish an indirect ELISA assay for SFTSV antibody,which possesses good specificity,sensitivity and reproducibility.This method might be applied to detect human SFTSV clinical serum samples.

Objective:To explore the diagnosis and treatment of humeral medial epicondyle fracture combined with radial neck fracture in children and adolescents.Methods:The clinical data were retro-spectively analyzed of the 12 pediatric patients with fractures of the humeral medial epicondyle plus the radial neck who had been admitted from February 2015 to August 2021 to Department of Pediatric Orthopedics, The Second Hospital of Fuzhou. There were 6 males and 6 females, with an age of (11.1 ± 2.5) years. According to the Papavasiliou classification, the humeral medial epicondyle fractures were type Ⅱ in 7 cases, type Ⅲ in 2 cases and type Ⅳ in 3 cases; according to the Judet classification, the radial neck fractures were type Ⅰ in 3 cases, type Ⅱ in 4 cases and type Ⅲ in 5 cases. Two Judet-Ⅰ radial neck fractures were missed by X-ray exam-ination but diagnosed by CT examination. Of the humeral medial epicondylar fractures, 9 were treated by open reduction and hollow screwing and 3 by closed reduction and Kirschner wiring. Of the radial neck fractures, 8 were treated by closed reduction and elastic intramedullary nailing and 4 conservatively. Fracture healing was followed up by postoperative radiographs. At the last follow-up, the carrying angles were measured, Kim Elbow Function Score (KEPS) was used to evaluate the functional recovery of the injured limb, and related complications were recorded.Results:All the 12 patients were followed up for (40.0±25.6) months. Fractures headed after (6.3±1.2) weeks. At the last follow-up, the carrying angle was 15.5°±2.6° on the injured side and 14.7°±2.0° on the healthy side, showing no significant difference ( P>0.05); KEPS was (96.3±5.3) points on the injured side and (98.8±2.3) points on the healthy side, showing no significant difference either ( P>0.05). No incision infection, bone nonunion, elbow valgus, joint stiffness or other complications were found; the postoperative elbow stability recovered well. Conclusions:As the fracture of the humeral medial epicondyle combined with the radial neck fracture is a special type of injury of straightened elbow during valgus stress in children and adolescents, it is likely to be missed in diagnosis. The goal of treatment is good functional recovery by restoring the articular match and elbow stability.

Objective: To analyze the current status of work-related musculoskeletal disorders (WMSDs), work fatigue and musculoskeletal pain in Chinese occupational population, and to study the relationship between work fatigue and musculoskeletal pain and WMSDs. Methods: A total of 66 961 employees from 323 enterprises in 15 key industries in China were selected as the study subjects using stratified cluster sampling method. The incidence of WMSDs in the past year was investigated using the Chinese version of the Musculoskeletal Disorders Questionnaire, and the work fatigue and musculoskeletal pain were investigated using Borg 6-20 Rating of Perceived Exertion Scale and visual analogue scale. The data were standardized using the age composition data of 18 to 60 years from the seventh national population census. Results: The standardized annual incidence of WMSDs was higher in the front-line workers than that in the administrative and other supportive staff (38.82% vs 36.30%). The detection rates of work fatigue and musculoskeletal pain in the study subjects were 44.54% and 63.08%, respectively. The result of S-curve fitting showed that the risk of WMSDs increased with the level of work fatigue (P<0.01). Among the front-line workers, the average of monthly fatigue frequency in the neck, shoulder, lower back, upper back, wrist/hand, foot and ankle, knee, leg, and elbow were higher in the group with WMSDs compared to those without WMSDs (all P<0.01). The pain degree of musculoskeletal pain was higher in all nine sites in the fatigued group than in the no-fatigue group (all P<0.01). The standardized detection rate of musculoskeletal pain was higher in the fatigued group than in the non-fatigued group (80.38% vs 25.71%). The work fatigue was moderate and positively correlated with musculoskeletal pain in all seven sites except the lower back and elbow, with Kendall Tau-b correlation coefficients ranging from 0.423 to 0.546 (all P<0.01). Conclusion: There is a good correlation between work fatigue and local musculoskeletal pain, work fatigue and WMSDs in Chinese occupational population. Implementing ergonomic interventions to control the development of work fatigue can be an effective measure for preventing WMSDs.

Objective:To investigate the biomechanical properties of a new pediatric femoral neck system in the fixation of pediatric femoral neck fractures with a free fracture fragment.Methods:Ten Sawbones model bones were randomly divided into 2 even groups ( n=5), all of which were made into Delbet Type Ⅱ femoral neck fractures with a Pauwels angle of 70°. A free bone block was removed from the bottom at the proximal end of the fracture to simulate a femoral neck fracture with a free fragment. Group A were fixed with traditional inverted triangle cannulated screws, and group B with a new pediatric femoral neck system. After the 2 groups of specimens were placed on a biomechanical testing machine, each specimen was subjected to a static axial compression test, an anti-torsion test and a cyclic load test in turn. The biomechanical results were compared between groups A and B in aspects of axial compression stiffness, torsional stiffness and maximum displacement difference. Results:The axial compression stiffness [(321.718±5.770) N/mm] and torsional rigidity [(1.448±0.079) N·m/°] in group B were significantly higher than those in group A [(266.722±4.788) N/mm and (1.282±0.023) N·m/°] ( P<0.05). The maximum displacement difference in the cyclic load test in group B [(0.063±0.038) mm] was also significantly smaller than that in group A [(0.117±0.056) mm] ( P<0.05). Conclusion:In fixation of pediatric femoral neck fractures with a free fracture fragment, the new pediatric femoral neck system can lead to better biomechanical stability than the traditional inverted triangle cannulated screws.

Background Prolonged awkward postures during occupational activities can lead to excessive musculoskeletal load on the wrist of workers and symptoms such as wrist pain or discomfort. Objective To survey the prevalence of wrist pain among workers in 10 key industries and analyze its correlation with wrist working postures. Methods By using stratified cluster sampling method, workers from 10 key industries, such as footwear manufacturing industry, shipbuilding manufacturing industry, and automobile manufacturing industry, were selected from seven regions in North China, East China, Central China, South China, Southwest China, Northwest China, and Northeast China. The demographic information, wrist working postures, pain in wrist of the workers were collected through a cross-sectional survey. Pearson χ² test was used to compare prevalence by selected factors, trend χ² test for between group comparison, and unconditional logistic regression models for the association of wrist working postures with wrist pain. Results There were 64052 workers enrolled in this survey, and 56286 provided valid questionnaires (the effective rate was 87.8%). According to the survey, the prevalence of wrist pain was 23.3% (13112/56286), and the industries with higher prevalences were footwear manufacturing (27.1%, 1927/7106), automobile manufacturing (24.9%, 5378/21560), and shipbuilding and related equipment manufacturing (24.4%, 850/3488) industries. Finger pinching (OR=2.09, 95%CI: 1.95-2.24), frequent wrist bending (OR=2.03, 95%CI: 1.92-2.15), fixed wrist bending (OR=1.77, 95%CI: 1.69-1.85), wrist on hard edge (OR=1.34, 95%CI: 1.28-1.40), and arms over shoulders (OR=1.11, 95%CI: 1.05-1.17) increased the risk of reporting wrist pain. Conclusion Awkward postures are related to wrist pain among workers in selected 10 key industries. The related factors are wrist on hard edge, frequent wrist bending, finger pinching, fixed wrist bending, and arms over shoulders.

Three cases of vibrio vulnificus-associated necrotizing fasciitis are presented. All patients showed a rapidly progressing, swelling, redness in the limb after eating seafood. Additionally, they presented with multiple organ dysfunction syndromes affecting the heart, lung, liver, kidney, coagulation, and blood. Vibrio vulnificus related necrotizing fasciitis is a fatal soft-tissue infection with high mortality. These are essential to improve survival by early clinical suspicion and immediate surgical intervention.