Objective:To investigate the relationship between epicardial adipose tissue (EAT) and frequent premature ventricular contractions (PVC) based on no-contrast chest CT scanning and evaluate the predictive value of EAT for high PVC loading levels.Methods:A case-control study was conducted to collect patients with PVC from January 2021 to June 2023 in the First Affiliated Hospital of Xinjiang Medical University. The study subjects were divided into a PVC high-load group (≥20%) and a PVC low-load group (<20%) based on the level of PVC loading in the 24-hour Holter electrocardiography monitoring. The parameter characteristics of EAT were obtained from no-contrast chest CT images. Multivariate logistic regression model analysis was used to assess the factors associated with high PVC loading levels, and the receiver operating characteristic (ROC) curve was used to assess the predictive value of the model.Results:A total of 166 subjects were included in the study, including 50 in the PVC high-load group and 116 in the PVC low-load group. Compared with the PVC low-load group, EATV was significantly increased in the high-load group ( Z=4.83, P<0.001), and EATA was significantly lower in the high-load group than in the low-load group ( t=-3.95, P<0.001). However, there was no statistically significant difference for the comparison of EATD ( Z=-1.56, P=0.120). Multivariate logistic regression model analysis showed that high EATV and low EATA were factors of high PVC loading levels [EATV: OR=1.01 (95% CI: 1.00-1.02), EATA: OR=1.16 (95% CI: 1.02-1.32)]. The area under the ROC curve for predicting high PVC loading levels by EATV and EATA was 0.79 (95% CI: 0.71-0.86). Conclusion:EATV and EATA are factors of high PVC loading levels and have predictive value for high PVC loading levels.

Objective:To investigate the relationship between epicardial adipose tissue (EAT) and frequent premature ventricular contractions (PVC) based on no-contrast chest CT scanning and evaluate the predictive value of EAT for high PVC loading levels.Methods:A case-control study was conducted to collect patients with PVC from January 2021 to June 2023 in the First Affiliated Hospital of Xinjiang Medical University. The study subjects were divided into a PVC high-load group (≥20%) and a PVC low-load group (<20%) based on the level of PVC loading in the 24-hour Holter electrocardiography monitoring. The parameter characteristics of EAT were obtained from no-contrast chest CT images. Multivariate logistic regression model analysis was used to assess the factors associated with high PVC loading levels, and the receiver operating characteristic (ROC) curve was used to assess the predictive value of the model.Results:A total of 166 subjects were included in the study, including 50 in the PVC high-load group and 116 in the PVC low-load group. Compared with the PVC low-load group, EATV was significantly increased in the high-load group ( Z=4.83, P<0.001), and EATA was significantly lower in the high-load group than in the low-load group ( t=-3.95, P<0.001). However, there was no statistically significant difference for the comparison of EATD ( Z=-1.56, P=0.120). Multivariate logistic regression model analysis showed that high EATV and low EATA were factors of high PVC loading levels [EATV: OR=1.01 (95% CI: 1.00-1.02), EATA: OR=1.16 (95% CI: 1.02-1.32)]. The area under the ROC curve for predicting high PVC loading levels by EATV and EATA was 0.79 (95% CI: 0.71-0.86). Conclusion:EATV and EATA are factors of high PVC loading levels and have predictive value for high PVC loading levels.

Objective:To determine the relationship between tibial plateau stresses and malunion by exploring the changes in mechanical conduction in the knee joint after malunion of Hoffa fracture of the tibial plateau.Methods:This study selected 28 knee joint specimens treated with formalin for preservation, half of which were from male and half from female individuals with an age of (51.4±9.5) years. Their structures were intact, and flexion-extension activities normal. X-ray examinations excluded osteoporosis, tuberculosis, and diseases that could have potentially affected bone quality. The knee specimens were divided into a control group (intact tibia) ( n=4) and 6 groups of tibial plateau Hoffa fracture malunion model: 3 vertical malunion groups (groups V1, V2, and V3, with a vertical displacement of 1, 2, and 3 mm, respectively, n=4) and 3 separation malunion groups (groups S3, S5, and S7, with a separation displacement of 3, 5, and 7 mm, respectively), with half males and half females in each group. After a 600N vertical load was applied at passive knee flexions at 0°, 30°, 60°, 90°, and 120°, the stress levels in the medial and lateral compartments of the knee joint were measured using pressure-sensitive films. Results:Under a vertical load of 600 N, when the knee joint was in a neutral position (flexion of 0°), the differences in the medial and lateral tibial plateau stress values were not statistically significant between the malunion models groups and the control group ( P>0.05). When the knee flexion increased to 30°, the medial tibial plateau stress in the V3 and S7 groups was significantly greater than that in the control group ( P<0.05). At a knee flexion of 60°, the medial plateau stress was significantly greater in the V3, S5 and S7 groups than that in the control group, and the differences were significantly greater than the comparisons at a knee flexion of 30° (all P<0.05). When the knee flexion was 90°, the medial plateau stress in the V2, V3, S5 and S7 groups was significantly greater than that in the control group ( P<0.05), but the lateral tibial plateau stress in the V3 group was significantly smaller than that in the control group ( P<0.05). When the knee flexion was further increased to 120°, the differences in the medial and lateral plateau stress values were statistically significant between all the malunion groups and the control group ( P<0.05), and the differences significantly greater than the comparisons at a knee flexion of 90° (all P<0.05). Under a vertical load of 600 N, the differences in the stresses on the medial and lateral plateaus were not statistically significant between the control group and all the malunion groups at a knee flexion of 0° ( P>0.05). When the knee flexion increased to 30°, the difference between the medial and lateral stresses was not statistically significant in the control group ( P>0.05), but was statistically significant in the V3 and S7 groups ( P<0.05). When the knee flexion reached 60°, 90°, and 120°, the differences between the medial and lateral tibial plateau stresses in all the groups were statistically significant ( P<0.05). Conclusions:The peak knee stresses after malunion of Hoffa fracture of the tibial plateau correlate with the severity of malunion and knee flexion angles. The mechanical properties are not significantly different between a mild malunion knee and a normal knee, but a significant displacement (vertical displacement >2 mm and separation displacement ≥5 mm) may increase the peak knee stresses to increase the risk of knee osteoarthritis. When the severity of malunion is certain, an increase in knee flexion angle increases the difference in the peak stress between the medial and lateral tibial plateaus, thus increasing the risk of knee osteoarthritis.

The neutrophil-to-lymphocyte ratio (NLR), the ratio of inflammatory cell counts in the blood, reflects the changes of neutrophils and lymphocytes in the inflammatory system in the peripheral blood. More and more scholars have found that NLR increases in patients with bone and joint injury, which can be used to predict postoperative mortality, infection, deep vein thrombosis, pain and other complications. This article is intended to review the application of NLR in bone and joint injury and related complications, providing reference for clinical application of NLR.

Objective:To compare the biomechanical properties between triangular supporting fixation and conventional dynamic hip screw (DHS) fixation in the treatment of femoral intertrochanteric fractures.Methods:Eight pairs of 16 femoral specimens with an average death age of 51.9 years were used in this study. After thawing, they were randomly divided into an experimental group ( n=8) and a control group ( n=8) according to the left or right laterality. They were made models of femoral intertrochanteric fracture of AO 31-A1 type with strain gauges pasted. The experimental group was subjected to fixation with double triangu-lar supporting and the control group conventional DHS fixation to achieve anatomical reduction. The specimens were then mounted onto a biomechanical testing machine and subjected to loading till 400 N at a rate of 10 N/s. The values of overall deformation of the specimens and strain at 16 selected sites were recorded and compared between the 2 model groups. Results:Under the load of 400 N, the overall deformation was (0.31±0.13) mm for the experimental group and (0.49±0.21) mm for the control group, showing a significant difference ( t=-2.456, P=0.023). The strain values in front of femoral neck, upon front fracture line, at inferior-lateral, inferior-median and inferior-interior sites of front fracture line, at the root of anterior fixation screw, below medial femoral neck fracture line, behind femoral neck, at superior-lateral, superior-median and superior-interior sites of posterior fracture line, below posterior fracture line, at superior and inferior roots of posterior fixation screw, at points parallel to the fixation screw in front of and behind femoral shaft were, respectively, -244.90, 13.16, -71.77, -124.38, -366.89,121.62, -10.94, -166.00, -54.93, -367.38, -608.93, -69.09, 326.50, 133.14, 52.97, and -185.82 in the experimental group and -24.62, -40.39, -36.99, -120.97, -486.38, 99.20, 35.36, -205.67, -74.30, -566.01, -1, 085.40, -77.41, 334.34, 114.08, 38.50, and -235.74 in the control group. Internal fixation failure occurred in one specimen in the control group after 1,759 cycles of loading but in none in the experimental group. Conclusion:For femoral intertrochanteric fractures, double triangular supporting fixation may result in less overall deformation and is more consistent with the normal biomechanical conduction of the femur than conventional DHS fixation.

Objective:To compare the biomechanical properties of triangular supporting fixation and Gamma nail fixation for intertrochanteric fractures of the femur.Methods:The femoral CT imaging data provided by a healthy adult male volunteer aged 40 years, height 172 cm, and weight 75 kg were used to reconstruct the femur model using Mimics 21.0 software and Geomagics 2013 software. Evans type I intertrochanteric fracture models were established using UG12.0 software, and Gamma nail and triangular supporting intramedullary nail models were reconstructed to simulate intertrochanteric fracture internal fixation, respectively. In Abaqus software, two internal fixation models of Gamma nail and triangular supporting intramedullary nail in standing state are simulated, and the stress peaks of the main nail, fixation screw and bone substance were collected, also the stress peak of supporting screw of the triangular supporting intramedullary nail is obtained. Additionally, the maximum displacement of the fracture model fixed by Gamma nail and triangular supporting intramedullary nail is measured.Results:Under the load of 1 200 N, the peak stress of the two fracture internal fixation models was located in the main nail, in which the peak stress of the triangular supporting intramedullary nail was 233.73 MPa, which was 11.9% lower than that of the Gamma nail (265.21 MPa); the peak stress of the fixation screw was located in the contact area between the pressure screw and the main nail, which was 23.2% lower in triangular supporting intramedullary nail than that of the Gamma nail (138.86 MPa vs. 180.75 MPa); the peak stress of the bone model was located in the medial cortex of the femur, which was 61.67 MPa and 32.38 MPa, respectively, 47.5% lower in the triangular supporting intramedullary nail than that of the Gamma nail; the peak stress of the supporting screw in the triangular supporting intramedullary nail was 92.04 MPa. The maximum displacement of the fracture model fixed with triangular supporting intramedullary nail was 17.34 mm, which was 10.5% less than the maximum displacement of the fracture model fixed with Gamma nail (19.37 mm). Conclusion:Compared with Gamma nail, triangular supporting intramedullary nail fixation can significantly improve the stability of intertrochanteric fractures and stress distribution as well as reduce stress peak and stress concentration area, which is helpful to improve the efficacy of intertrochanteric fractures.

Background The surgery for retinal detachment induced by macular hole in high myopic eye has a lower success rate in comparison with other rhegmatogenous retinal detachment.A combination procedure of vitrectomy and heavy silicone oil tamponade for retinal detachment induced by macular hole in high myopic eye has been used,but different outcomes are reported.Objective This study was to assess the efficacy of heavy silicone oil tamponade for the treatment of retinal detachment with macular hole in high myopic eye.Methods The clinical data of 20 eyes of 20 patients who received vitrectomy combined heavy silicone oil tamponade surgery for retinal detachment induced by macular hole in high myopia under the informed consent in Beijing Tongren Eye Center from September 2007 to December 2009 were retrospectively analyzed.The 20 G vitrectomy was used during the surgery.In addition,other procedures,such as epiretinal membrane peeling,retinotomy,endo-laser photocoagulation,phacoemulsification and intraocular lens (IOL) implantation were optionally performed as necessary.No special position was required after the surgery.Heavy silicon oil was removed via pars plana,and retinal reattachment after heavy silicon oil removal was defined as success of surgery.Postoperative LogMAR vision,intraocular pressure,retinal reattachment and complications were observed and evaluated.Results The preoperative average spherical equivalent refractive error was (-14.3 ±3.0) D in the eyes.Among the 20 eyes,there were 7 (35％) recurrent retinal detachment and 7 eyes (35％) complicated with choroidal detachment preoperatively.After surgery,the retinas were reattached in 95％ eyes (19/20),including retinal reattachment after first operation in 18 eyes (90％) and after second surgery in 1 eye (5％).A localized retinal detachment was still existed after a second surgery in the other 1 eye.The mean LogMAR vision improved from preoperative 2.77 ±0.81 to postoperative 1.22±0.46 (P =0.000).All the phakic eyes developed different degrees of sub-capsular cataract.Long-term ocular hypertension was found in 2 eyes after surgery.Conclusions The combination of vitrectomy and heavy silicone oil endotamponade is a safe and effective approach to retinal detachment with macular hole in high myopic patients.This procedure may improve vision and offers comfortable position after surgery for the patients.