目的:探讨锁骨中段骨折最适内固定方式。方法:总结1990年1月～2007年6月426例锁骨中段骨折采用钢丝、克氏针、钢板内固定治疗，术后随访6个月～12个月，对不同内固定疗效进行评估。结果:钢丝固定53例，固定失败18例，优良率66.04%；克氏针固定97例，固定失败12例，优良率87.63%；钢板固定276例，固定失败19例，优良率93.12%。结论:钢丝固定锁骨中段骨折不确切，克氏针固定适应症窄，钢板内固定可靠，对抗上肢旋转剪力、内外张力，有利于骨折愈合和锁骨功能的早期建立。在应用的四种类型钢板中:解剖钢板、重建钢板术后并发症少，是治疗锁骨中段骨折较为理想的内固定方式。
Signal classification is a key of brain-computer interface (BCI). In this paper, we present a new method for classifying the electroencephalogram (EEG) signals of which the features are heterogeneous. This method is called wrapped elastic net feature selection and classification. Firstly, we used the joint application of time-domain statistic, power spectral density (PSD), common spatial pattern (CSP) and autoregressive (AR) model to extract high-dimensional fused features of the preprocessed EEG signals. Then we used the wrapped method for feature selection. We fitted the logistic regression model penalized with elastic net on the training data, and obtained the parameter estimation by coordinate descent method. Then we selected best feature subset by using 10-fold cross-validation. Finally, we classified the test sample using the trained model. Data used in the experiment were the EEG data from international BCI Competition Ⅳ. The results showed that the method proposed was suitable for fused feature selection with high-dimension. For identifying EEG signals, it is more effective and faster, and can single out a more relevant subset to obtain a relatively simple model. The average test accuracy reached 81.78%.
The treatment of chronic thoracoabdominal aortic dissection aneurysm remains a major challenge in aortic surgery. Open surgery is the mainstream treatment at present. New devices for endovascular treatment of chronic thoracoabdominal aortic dissection are gradually applied in clinical practice. The hybrid procedure is a combination of open and endovascular procedures. The appropriate treatment should be selected according to the patient's age, anatomy, genetic aortic disease, and comorbidities.
ObjectiveTo investigate revision reasons and prosthesis selection of Crowe Ⅳ developmental dysplasia of the hip (DDH) after total hip arthroplasty (THA). MethodsA clinical data of 14 patients (15 hips) with Crowe Ⅳ DDH, who underwent a revision hip arthroplasty between January 2008 and May 2018, was retrospectively reviewed. There were 1 male (1 hip) and 13 females (14 hips). The age ranged from 27 to 63 years (mean, 45.0 years). There were 7 cases of left hip, 6 cases of right hip, and 1 case of bilateral hips. The prosthetic interfaces of primary THA were metal-on-polyethylene (MOP) in 9 hips, ceramic-on-ceramic (COC) in 4 hips, ceramic-on-polyethylene (COP) in 1 hip, and ceramic-on-metal in 1 hip. The time from primary THA to revision was 3-204 months (mean, 65.0 months). The causes of revision included aseptic loosening in 7 hips, dislocation in 3 hips, periprosthetic joint infection in 2 hips, osteolysis in 1 hip, nonunion of osteotomy in 1 hip, and a small-angle of femoral anteversion in 1 hip. Preoperative Harris score was 54.1±17.8 and the range of motion (ROM) of flexion was (92.7±20.2)°. Preoperative X-ray films showed the acetabular bone defect in 11 hips and osteolysis of femoral side in 4 hips. During the revision, the prostheses with COP and COC interfaces were used in 5 hips and 10 hips, respectively. Both acetabular and femoral revisions were performed in 11 hips and only femoral revision was performed in 4 hips.ResultsThe mean operation time was 3.7 hours (range, 1.5-6.0 hours). The mean intraoperative blood loss was 940.0 mL (range, 200-2 000 mL). All patients were followed up 16-142 months (mean, 73.9 months). Postoperative X-ray films showed no difference in inclination and anteversion between primary THA and revision (P>0.05). The height of rotation center and offset after revision were higher than those after primary THA, and the difference in offset was significant (P<0.05). At last follow-up, the Harris score and ROM of flexion were 85.0±7.3 and (115.0±17.0)°, respectively, which were significantly higher when compared with those before revision (t=8.909, P=0.000; t=4.911, P=0.000). Three hips underwent a re-revision operation. All protheses were fixed well and no radiolucent line, loosening, or subsidence was observed at last follow-up.ConclusionThe most common reason for revision in patients with Crowe Ⅳ DDH after THA was aseptic loosening. Due to high activity demand of this population, the prosthesis with MOP interface should be prevented and the prosthesis with COC interface could be alternative. Metal block, cup-cage, and reinforcement ring were reasonable solutions for reconstruction of acetabulum with severe bone defects and have satisfactory effectiveness. S-ROM prosthesis should be the preferred stem for neither primary THA or revision.
Evidence synthesis is the use of standardized, clear and rigorous methods to bring together and merge existing research data, knowledge and information, focusing on specific research questions, in order to provide a basis for relevant medical and health decision-making. At present, there are many types of evidence synthesis methods, the number of related applied researches has proliferated, however, it is easy to confuse different methods, which leads to problems such as misuse and abuse. The choice of inappropriate synthesis method will reduce the credibility and applicability of evidence. Clarifying the path and link of the selection of evidence synthesis methods will play a positive role in promoting the standardization of evidence-based evaluation. Thus, this paper briefly describes the development and classification of evidence synthesis methods, and reviews 18 representative evidence synthesis methods and its application examples in the medical field including systematic review. It also introduces the "Right Review", an evidence synthesis method selection tool that has been developed and put into use in recent years, and clarifies the limitations of the current selection tools and methods. At the same time, referring to existing tools, theories, and models, the selection path for different evidence synthesis methods and the decision process of evidence synthesis are proposed to provide reference for researchers to choose the evidence synthesis method reasonably.
Due to the high complexity and subject variability of motor imagery electroencephalogram, its decoding is limited by the inadequate accuracy of traditional recognition models. To resolve this problem, a recognition model for motor imagery electroencephalogram based on flicker noise spectrum (FNS) and weighted filter bank common spatial pattern (wFBCSP) was proposed. First, the FNS method was used to analyze the motor imagery electroencephalogram. Using the second derivative moment as structure function, the ensued precursor time series were generated by using a sliding window strategy, so that hidden dynamic information of transition phase could be captured. Then, based on the characteristic of signal frequency band, the feature of the transition phase precursor time series and reaction phase series were extracted by wFBCSP, generating features representing relevant transition and reaction phase. To make the selected features adapt to subject variability and realize better generalization, algorithm of minimum redundancy maximum relevance was further used to select features. Finally, support vector machine as the classifier was used for the classification. In the motor imagery electroencephalogram recognition, the method proposed in this study yielded an average accuracy of 86.34%, which is higher than the comparison methods. Thus, our proposed method provides a new idea for decoding motor imagery electroencephalogram.
Objective To systematically evaluate the clinical effects of remote ischaemic preconditioning (RIPC) in elective vascular surgery. Methods Electronic searches were conducted in The Cochrane Library, PubMed, EMbase, Web of Science, CNKI, Wanfang Data, VIP Database, and CBM. Relevant randomized controlled trials (RCTs) were screened according to inclusion and exclusion criteria. Meta-analysis was performed using RevMan 5.3 software, and the risk of bias was assessed using the Cochrane risk of bias tool. Results A total of 15 studies involving 1 382 patients were included. The meta-analysis results showed no statistically significant difference between RIPC and non-RIPC groups in reducing perioperative mortality in elective vascular surgery (P>0.05). There were also no statistically significant differences between the two groups of vascular surgery patients regarding the incidence of myocardial infarction, renal injury, postoperative stroke, postoperative length of hospital stay, duration of surgery or total anesthesia time, or the incidence of limb injury, arrhythmia, heart failure, and pneumonia (P>0.05). Conclusion For patients undergoing elective vascular surgery, there are no significant differences between RIPC and non-RIPC in terms of perioperative mortality and other clinical endpoint outcomes.
Surgerical treatment has been used for portal hypertension over a hundred years, and has evolved from various portosystemic shunts to devascularizations and selective shunts. Selective shunting, which has the advantages of long-term prevention from recurrent variceal bleeding and maintenance of hepatic portal vein perfusion, has developed from single distal splenorenal shunt to various procedures including distal splenocaval shunt, coronary caval shunt, coronary renal shunt, etc. Selective shunting can also be achieved after reconstruction of spontaneous portosystemic shunt. Preoperative portal venous system CT angiography, intraoperative ultrasound Doppler and portal vein pressure measurements may provide patients with a more reasonable treatment of choice.
Medical image fusion realizes advantage integration of functional images and anatomical images. This article discusses the research progress of multi-model medical image fusion at feature level. We firstly describe the principle of medical image fusion at feature level. Then we analyze and summarize fuzzy sets, rough sets, D-S evidence theory, artificial neural network, principal component analysis and other fusion methods' applications in medical image fusion and get summery. Lastly, we in this article indicate present problems and the research direction of multi-model medical images in the future.