Objective:To evaluate the efficacy of arthroscopic suture combined with perforator tendon double reduction and Endobutton plate technique for the treatment of tibial avulsion fracture of posterior cruciate ligament (PCL).Methods:A retrospective case series study was conducted to analyze the clinical data of 32 patients with tibial avulsion fracture of PCL, who were admitted to First People′s Hospital of Huizhou from January 2018 to October 2022. There were 19 males and 13 females, with age range of 18-65 years [(42.8±15.0)years]. By the Meyers-Mckeever classicfication, 27 patients were type II, and 5 type III. All the patients were treated with arthroscopic suture combined with perforator tendon double reduction and Endobutton plate technique to fix PCL tibial avulsion fracture at the insertion point. The fracture reduction was observed by X-ray films before discharge. Three months postoperatively, the fracture healing was observed by CT imaging, and the stability of knee joint was evaluated by posterior drawer test. The knee active range of motion, visual analogue score (VAS), Lysholm score, and International Knee Documentation Committee (IKDC) score were used to evaluate the pain and knee function before operation, at 3 months after operation, and at the last follow-up. Intraoperative and postoperative complications were observed.Results:All the patients were followed up for 6-36 months [(19.7±8.7)months]. The X-ray films showed satisfactory reduction of the fracture before discharge, and the CT showed that the fracture line was blurred to various degrees at 3 months after operation. Two patients had degree I positive posterior drawer test at 3 months after operation, and the rest were negative. The knee active range of motion was improved from 54.2°(45.0°, 70.0°) preoperatively to 124.8°(120.0°, 130.0°) at 3 months postoperatively and to 130.6°(125.0°, 135.0°) at the last follow-up (all P<0.01). The VAS was decreased from 5.1(3.0, 7.0)points preoperatively to 1.2(1.0, 2.0)points at 3 months postoperatively and to 0.1(0.0, 0.0)points at the last follow-up (all P<0.01). The Lysholm score was improved from 31.2(24.3, 37.0)points preoperatively to 73.6(69.3, 78.8)points at 3 months postoperatively and 92.6(91.0, 95.0)points at the last follow-up (all P<0.01). The IKDC score was increased from (20.9±7.1)points preoperatively to (59.2±8.9)points at 3 months postoperatively and to (77.5±7.0)points at the last follow-up (all P<0.01). Compared with 3 months after operation, the last follow-up showed significantly improved knee active range of motion, significantly decreased VAS, and significantly increased Lysholm score and IKDC score (all P<0.05). No intraoperative nerve vascular injury, postoperative incision infection, or lower limb venous thrombosis was observed. Conclusion:Arthroscopic suture combined with perforator tendon double reduction and Endobutton plate technique can achieve good reduction and high healing rate in patients with tibial avulsion fracture of PCL, with improved joint mobility, relieved pain, good recovery of knee joint function, and few complications.

Background Previous research indicated that isomers and alternatives of per- and polyfluoroalkyl substances (PFAS) probably disturb glucose metabolism; however, current epidemiological evidence on the associations of PFAS with fasting blood glucose is inconsistent. Besides, studies on the joint association of multiple components of PFAS and fasting blood glucose as well as the key component are scarce. Objective To evaluate the associations of PFAS isomers and alternatives with fasting blood glucose and their joint effects, as well as identify the key component among population without glucose metabolism problems. Methods We selected 923 adults without glucose metabolism problems or missing data from the Isomers of C8 Health Project in China (2015—2016). Serum PFAS isomers and alternatives and fasting blood glucose were measured using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) and automatic biochemical analyzer. We applied multiple linear regression to explore the associations of 16 pollutants which were detected among over 80% participants with fasting blood glucose. Meanwhile, we utilized qgcomp and Bayesian kernel machine regression (BKMR) models to explore the joint effects of PFAS isomers and alternatives mixture on target outcome indicators and identify the key component. Results The average age among the 923 participants in this study was (62.4±13.8) years old, including 472 men (51.1%) and 451 women (48.9%). Among selected PFAS isomers and alternatives, the highest serum concentration was ∑3+4+5m-PFOS (perfluoro-3/4/5-methylheptanesulfonate) with a median concentration of 10.20 ng·mL⁻¹. The concentrations of linear perfluorooctane sulfonate (n-PFOS, 9.61 ng·mL⁻¹), perfluorooctanoic acid (PFOA, 4.55 ng·mL⁻¹), linear perfluorohexane sulfonic acid (n-PFHxS, 2.48 ng·mL⁻¹), 6:2 chlorinated polyfluorinated ethersulfonic acid (6:2 Cl-PFESA, 1.90 ng·mL⁻¹), perfluoro-6-methylheptanesulfonate (iso-PFOS, 1.85 ng·mL⁻¹), perfluorobutanoic acid (PFBA, 1.81 ng·mL⁻¹), perfluorinated n-nonanoic acid (PFNA, 1.39 ng·mL⁻¹), and perfluoro-1-methylheptanesulfonate (1m-PFOS, 1.27 ng·mL⁻¹) were higher than 1.00 ng·mL⁻¹. After being adjusted for selected confounders, PFAS isomers and alternatives were positively associated with fasting blood glucose. With 1 ln unit concentration increment of 6:2 Cl-PFESA and PFNA, the estimated changes of fasting blood glucose were 0.18 (95%CI: 0.13, 0.23) mmol·L⁻¹ and 0.24 (95%CI: 0.18, 0.30) mmol·L⁻¹, respectively. The multi-pollutant models indicated a joint association of PFAS isomers and alternatives mixture with fasting blood glucose. The BKMR models reveals that as the quantiles of mixture elevated from the 50^th to the 75^th percentile, the values of fasting blood glucose increased 0.25 (95%CI: 0.21, 0.30) mmol·L⁻¹, and the posterior inclusion probability of PFNA was 0.92, implying that PFNA was the key component. Conclusion PFAS isomers and alternatives are positively associated with fasting blood glucose. PFNA is the key component of the joint association.

Background Studies on the association between greenness exposure and allergic rhinitis (AR) in children are mostly conducted in developed countries, and the conclusion is not consistent. Objective Using street view data to explore the association between greenness exposure and allergic rhinitis (AR) prevalence in Chinese children. Methods A cross-sectional study was conducted among 40868 children aged 2-17 years in three cities of Northeast China from 2012 to 2013, which consisted of 20886 (51.1%) boys and 19982 (48.9%) girls. The information of AR prevalence was obtained through questionnaire. Based on downloaded street view images from Tencent Maps, a green view index (GVI) of green vegetation (trees and grass) within 800 m and 1000 m buffer of the participants' schools was calculated by using artificial intelligence, and it was used as a surrogate of the greenness exposure. A mixed-effect logistic regression model was used to estimate the odds ratio (OR) of AR prevalence in children for per increase of inter-quartile range (IQR) of GVI. In addition, according to ambient PM_2.5 concentration, the participants were divided into a low PM_2.5 exposure group (≤56.23 μg·m⁻³) and a high exposure group (>56.23 μg·m⁻³) to investigate whether PM_2.5 was a modifier on the association between GVI and AR. Results The average age of the subjects was (10.40±3.68) years and 3 963 (9.7%) subjects reported diagnosed AR. Within 800 m buffer, an IQR increase in GVI for trees (IQR=0.031, OR=0.85, 95%CI: 0.81-0.90) and overall greenness (IQR=0.029, OR=0.86, 95%CI: 0.81-0.90) was associated with lower adjusted odds ratio of AR. The interaction between PM_2.5 and GVI was statistically significant (P< 0.1), that is, the negative associations of trees and overall greenness with AR were observed only at low PM_2.5 exposure levels. The sensitivity analysis results of GVI within 1000 m buffer was consistent with that within 800 m buffer. Conclusion Exposure to green vegetation, especially trees, may be associated with decreased risks of AR in children, and such associations may be more obvious in areas with a low PM_2.5 concentration.