Objective To evaluate the clinical efficacy of limited open reduction combined with percutaneous medial locking plate in treatment of Rüedi-Allg(o)wer type Ⅱ and Ⅲ closed tibial pilon fractures.Methods A retrospective case-control analysis was made on 45 cases of closed tibial pilon fractures treated surgically between June 2008 and December 2015.There were 33 males and 12 females,aged from 26-66 years (mean,44.6 years).All cases were unilateral tibial pilon fractures,among which 18 were on the left while 27 were on the right.Thirty-four cases were combined with fibular fractures.There were 14 cases of type Ⅱ fractures and 31 type Ⅲ fractures according to the Rüedi-Allg(o)wer classification.Using the Tscheme-Gotzen system to evaluate soft tissue injury,two patients were in grade 1,29 patients in grade 2,and five patients in grade 3.On the basis of surgical methods,the cases were divided into Group A,limited open reduction with percutaneous medial locking plate and Group B,conventional open reduction.The operation time,reduction quality,fracture healing time,American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale at final follow-up visit and complications were recorded and compared between the two groups.Results The operation time of Group A was shorter than that of Group B (P ＜ 0.05).All patients had been followed up for 12-24 months,among which Group A was 22.5 months and Group B was 20.0 months (P ＞ 0.05).Compared with Group B,Group A was superior in fracture healing time (P ＜ 0.05) and AOFAS ankle-hindfoot scale(P ＜0.05),but was inferior in reduction quality (P ＜ 0.05).Poor wound healing was observed in two cases in each group,yet there was no nonunion in all cases.Conclusion Compared with conventional open reduction,the limited open reduction combined with percutaneous medial locking plate has more advantages in operation time and fracture healing,which can achieve better ankle functions for closed tibial pilon fractures.

Objective: To analyze the risk factors of positive vertical resection margin of the postoperative specimens after endoscopic treatment of rectal neuroendocrine tumors (NET). Methods: A case-control study was performed. Clinical data of patients with rectal NET (G1) undergoing endoscopic treatment between January 2015 and June 2018 at the Department of Gastroenterology, Beijing Tsinghua Changgung Hospital were retrospectively collected. Inclusion criteria: cases underwent endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD), whose mucosal specimens were pathologically confirmed as NET, and NET was confined to the rectum by nuclide imaging examination before endoscopic treatment. Those with incomplete clinical data or follow-up data were excluded. Resected specimen was fixed and sliced every 2 mm, and when tumor cells were found to infiltrate the vertical cutting edge, the positive vertical margin was defined. Associations of gender, age, resection method, tumor diameter, lesion morphology (nodular lesions, biopsy or post-treatment scar-like changes), mitotic figure, Ki-67 index, etc. and positive vertical margin were analyzed. Univariate analysis was performed using binary logistic analysis and multivariate analysis was performed using logistic regression model. Results: A total of 133 patients with rectal NET were enrolled, including 93 males and 40 females, with an average age of (50.0±10.7) years. Sixty-four patients received EMR treatment and 3 patients (4.7%) had positive vertical margins. While 69 patients received ESD treatment and 13 (18.8%) had positive vertical margins. After endoscopic treatment, 16 cases (12.0%) were vertical positive margin, including 11 males and 5 females with an average age of (52.4±10.4) years. The lesion diameter was (9.0±4.7) mm. Univariate analysis showed that lesion diameter ≥10 mm (χ²=5.575, P=0.018) and scar-like changes (χ²=3.894, P=0.048) were significantly associated with positive vertical margin. Multivariate analysis showed that the lesion diameter ≥10 mm (OR=10.136, 95%CI: 2.114 to 48.591, P=0.004) was an independent risk factor for positive vertical margin of the specimen after endoscopic treatment of rectal NET. Conclusion The diameter of rectal NET ≥10 mm indicates a high risk for positive vertical margin after endoscopic treatment.

Objective:To investigate the relationship between renin-angiotensin system (RAS) and bone mineral density in children with glucocorticoids-induced osteoporosis (GIOP) .Methods:From Apr. 2020 to May. 2021, 53 children with GIOP were recruited in the Children’s Hospital of Taiyuan Maternal and Child Health Hospital and included in the observation group, and 47 children who received glucocorticoid therapy but did not suffer from GIOP were included in the control group. The levels of serum RAS components and bone mineral density of the two groups of pediatric patients were detected and compared, and the risk clinical indicators affecting bone mineral density and GIOP were analyzed.Results:There were no significant differences between the observation group and the control group in terms of gender, age, BMI, disease type, type of glucocorticoid use, use of anti-osteoporosis (OP) drugs, expression levels of Angiotensin converting enzyme 2 (ACE2) or angiotensin II (Ang Ⅱ) (all P>0.05) . The bone density value of the observation group was lower than those of the control group, and the levels of angiotensin converting enzyme (ACE) (1.19±0.23) , angiotensin receptor 1 (AT1R) (1.24±0.24) , angiotensin receptor 2 (AT2R) (1.14±0.17) , and Mas receptor (MasR) (1.11±0.28) were significantly higher than those of the control group (1.00±0.23, 1.00±0.25, 1.00±0.21, 1.00±0.20) , and the differences were statistically significant (all P<0.05) . Pearson analysis showed that bone mineral density was negatively correlated with the levels of ACE ( r=-0.34, P=0.013) , AT1R ( r=-0.41, P=0.002) and AT2R ( r=-0.34, P=0.014) , and stepwise regression model showed that ACE ( t=-2.21, P=0.032) and AT1R ( t=-2.92, P=0.005) were the main factors affecting bone mineral density. Logistic regression model analysis showed that bone mineral density ( OR=0.85, P<0.001) , Ang Ⅱ ( OR=0.53, P=0.041) and AT2R ( OR=2.00, P=0.024) were independent clinical risk factors affecting GIOP (all P<0.05) . Conclusion:RAS components ACE and AT1R are independent risk factors affecting bone mineral density in children with GIOP, and are significantly correlated with bone mineral density in children.