Cable Pin System versus K-wire Tension Band Fixation for Patella Fractures in Chinese Han Population: A Meta-analysis

This meta-analysis compared the therapeutic effect of cable pin system（CPS） with K-wire tension band（KTB） in the treatment of patella fractures among Chinese Han population. The databases of PubM ed, Cochrane library, China National Knowledge Infrastructure（CNKI）, Chinese Wan Fang and Chinese VIP were searched for studies on CPS versus KTB in the treatment of patella fractures among Chinese Han population. Literatures were screened according to the inclusion and exclusion criteria. The quality of the studies was assessed, and meta-analysis was performed using the Cochrane Collaboration＇s REVMAN 5.3 software. A total of 932 patients from 15 studies were included in this meta-analysis（426 fractures treated with CPS and 506 fractures treated with KTB）. There were significant differences in duration of hospital stay [mean difference（MD）=–1.07; 95% confidence interval（CI）： –1.71 to –0.43], fracture healing time（MD=–1.23; 95% CI： –1.68 to –0.77）, flexion degree of knee joint at 6 th month after operation（MD=14.82; 95% CI： 10.93 to 18.71）, incidence of postoperative complication [risk ratio（RR）=0.16; 95% CI： 0.09 to 0.27] and excellent-good rate of B？stman score（RR=1.09; 95% CI： 1.03 to 1.16） between the CPS group and KTB group, while no significant difference was found in operative time between the two groups（MD=–4.52; 95% CI： –11.70 to 2.67）. For the treatment of patella fractures among Chinese Han population, limited evidence suggests that the CPS is more suitable than the KTB when considering the hospital stay, fracture healing time, flexion degree of knee at 6 th month after operation, incidence of postoperative complication and excellent-good rate of B？stman joint score. Due to the limitation of high quality evidence and sample size, more large-scale randomized controlled trials are needed to validate the findings in the future.

A Study on a Wire Tension Adaptive Control System of a Multi-wire Saw in Computer Simulation

Based on the analysis of the mechanism of wire tension control by using torque motors in the multi-wire saw machining process, some mathematical models of a tension control system are studied, and an adaptive algo- rithm is designed for controlling the wire tension. In this algorithm of tension control, the rotation speeds and waving angle of motors are measured and fed back to the controller, and the NLMS（ normalized least mean squares） algorithm is used to calculate the adaptive correction value and control the wire tension accurately. The computer simulation results in Matlab software validate the high accuracy for controlling the system of the wire tension with the NLMS algorithm in the multi-wire saw machining process.

Effect of wire tension on different output responses during wire electric discharge machining on AISI 304 stainless steel

WEDM is used in machining conductive materials where it is required to obtained complicated and intricate shapes with high accuracy.Various applications are in the field of automobile,medical industries,aerospace etc.WEDM is an economical machining option with short product development cycle.Surface roughness,kerf width,Material removal rate,Recast layer hardness and surface microhardness in WEDM are most important responses.In this paper,effect of varied Wire tension on SR,KW,MRR,RCL hardness and surface microhardness on AISI 304 have been investigated.Pulse on time,pulse off time,current and dielectric fluid are taken as fixed parameter.Results show that Wire tension influences the SR,MRR and Surface microhardness and has no effect on kerf width in case of Stainless steel304.

Development of a portable and fast wire tension measurement system for MWPC construction

In a multi-wire proportional chamber detector（MWPC）, the anode and signal wires must maintain suitable tension, which is very important for the detector＇s stable and accurate performance. As a result, wire tension control and measurement is essential in MWPC construction. A high pressure3 He MWPC detector is to be used as the thermal neutron detector of the multi-functional reflectometer at China Spallation Neutron Source, and in the construction of the detector, we have developed a wire tension measurement system. This system is accurate,portable and time-saving. With it, the wire tension on an anode wire plane has been tested. The measurement results show that the wire tension control techniques used in detector manufacture are reliable.

Effect of Tension on Friction Coefficient Between Lining and Wire Rope with Low Speed Sliding

In order to obtain the exact friction coefficient between lining and wire rope,the tension of wire rope is stud-ied as a factor which affects this coefficient. A mechanical model of a wire rope subjected to axial load was established to determine the torque of the wire rope. The contact motion between lining and wire rope was regarded as a screw rota-tion and the axial force of the lining resulting from the torque of the wire rope was analyzed. Theoretical formulas re-lating tension of the wire rope and the friction coefficient was obtained. Experiments between lining and wire rope with low sliding speed were carried out with friction tester made by us. Experimental results show that increment of the fric-tion coefficient is proportional to that of the tension of the wire rope with a low sliding speed. The experimental results agree with the theoretical calculation; the errors are less than 6%,which proves the validity of the theoretical model.

带线锚钉+空心钉内固定治疗髌骨骨折的疗效

目的探讨带线锚钉+空心钉内固定治疗髌骨骨折的疗效。方法将60例髌骨骨折患者按照内固定方式不同分为观察组(采用带线锚钉+空心钉内固定治疗,30例)和对照组(采用克氏针张力带+钢丝捆扎内固定治疗,30例)。记录两组手术时间、骨折愈合情况、术后并发症发生率。采用Lysholm评分评价膝关节功能。结果患者均获得随访,观察组随访时间12~36(17.47±6.17)个月,对照组随访时间12~30(17.70±4.06)个月。手术时间观察组短于对照组(P<0.01)。两组骨痂形成时间2~3个月,骨折愈合时间4~6个月。术后并发症发生率观察组低于对照组(P<0.05)。末次随访时Lysholm评分评价的膝关节功能优良率两组比较差异无统计学意义(P>0.05)。结论带线锚钉+空心钉内固定治疗髌骨骨折能有效缩短手术时间、降低手术难度、减少术后并发症的发生,而且内固定稳定、牢靠,患者术后膝关节功能恢复良好。

牵张放线智能感应及安全控制技术研究

为促进牵张设备的发展,实现电网建设目标,分析了牵张放线施工存在的问题及发展现状,通过建立动力学方程组模型和放线系统方程组,设计了放线滑车监控系统。该系统采用多参数监控设备,基于传感器信息智能集成技术将空间姿态、载荷等参数的监控单元进行集成,实现了多个参数数据的实时采集和传输,包括溜车的三轴姿态角度、空间位置及载重信息等。结合线路建设计算方法,对牵引绳索、导线不同阶段的运行状态进行分析,与监测数据进行对比,实时预警滑车在施工过程中载重量的变化及空间姿态角度的变化,以提升施工安全性及施工效率。

不同内固定方式固定Herscovici B型及C型内踝骨折的有限元分析

目的 应用有限元分析法,探究不同内固定方式及不同置入角度固定Herscovici B型及C型内踝骨折的生物力学稳定性。方法 应用Mimics 19.0软件建立胫骨远端三维模型,通过Geomagic Studio 2013及SolidWorks 2017软件对模型进行加工以及内置物的装配,建立Herscovici B型及C型内踝骨折以及全螺纹螺钉、半螺纹螺钉、克氏针张力带三种不同内固定模型。运用ANSYS Workbench 17.0有限元分析软件对模型进行参数设定以及载荷施加,分析骨折端应力、位移及内置物应力及位移等情况,并进行统计分析。结果 对于Herscovici B型骨折,在相同载荷下,三种内固定方式均在与骨折线成130°~140°角范围内的置入角度下最稳定(P<0.05);载荷及内置物置入角度都相同的条件下,全螺纹螺钉组相对于其他两种内固定方式更稳定。对于Herscovici C型骨折,在相同载荷下,三种内固定方式均在与骨折线成130°~140°角范围内的置入角度下最稳定(P<0.05);载荷及内置物置入角度都相同的条件下,全螺纹螺钉组相对于其他两种内固定方式更稳定。结论 针对Herscovici B型及C型骨折,全螺纹螺钉相较于半螺纹螺钉及克氏针张力带稳定性更佳,且置入角度为与骨折线成130°~140°角范围内的稳定效果更好。这对临床治疗Herscovici B型及C型内踝骨折具有参考意义。

四黄散联合间断垂直钢丝缝合加张力带对髌骨下极骨折患者膝关节活动度及骨折愈合时间的影响

目的:观察四黄散联合间断垂直钢丝缝合加张力带对髌骨下极骨折患者膝关节活动度及骨折愈合时间的影响。方法:选取2021年9月至2022年9月丰城市中医院收治的髌骨下极骨折患者40例,按照随机数字表法分为对照组和试验组,每组20例。两组患者均给予切开复位内固定,对照组给予间断垂直钢丝缝合联合张力带治疗,试验组给予四黄散联合间断垂直钢丝缝合加张力带治疗。观察两组患者术后6周、3个月、6个月、1年及末次随访时膝关节疼痛评分、屈伸活动范围(range of motion, ROM)、Bostman评分、骨折愈合时间、各项临床指标及并发症发生情况。结果:试验组术后6周、3个月、6个月、1年膝关节疼痛评分均低于对照组,差异有统计学意义(P<0.05)。试验组术后6周、3个月、6个月、1年ROM、Bostman评分高于对照组,差异有统计学意义(P<0.05)。试验组术后1年骨折愈合时间、各项临床指标均优于对照组,并发症发生率低于对照组,差异有统计学意义(P<0.05)。结论:四黄散联合间断垂直钢丝缝合加张力带能改善髌骨下极骨折患者膝关节功能,降低术后并发症发生率,促进骨折早日愈合。

两种方法治疗髌骨骨折的疗效比较

目的比较经皮微创钛缆与经皮微创克氏针张力带内固定治疗髌骨骨折的疗效。方法将98例髌骨骨折患者根据手术方式不同分为A组(采用经皮微创钛缆内固定治疗,49例)与B组(采用经皮微创克氏针张力带内固定治疗,49例)。记录两组手术情况、骨折复位及愈合情况、膝关节屈曲活动度、术后并发症发生情况,采用Bostman评分标准评定膝关节功能。结果患者均获得随访,时间12~24(15.9±3.8)个月。手术时间、术后3 d疼痛VAS评分、住院时间两组比较差异均无统计学意义(P>0.05)。住院费用A组高于B组(P<0.01)。术后X线片显示骨折复位良好。骨折均愈合,时间11~16周。术后3个月Bostman评分优良率、末次随访时膝关节屈曲活动度两组比较差异均无统计学意义(P>0.05)。术后并发症发生率B组高于A组(P<0.05)。结论经皮微创钛缆内固定与经皮微创克氏针张力带内固定治疗髌骨骨折均可获得满意疗效,经皮微创钛缆内固定术后并发症更少,但也增加了患者的住院费用。

提升机钢丝绳张力检测系统设计研究

基于提升机钢丝绳加速提升、减少爬坡过程中持续的高张力运行工况,提出一种提升机钢丝绳张力检测系统设计方案。分析了张力检测系统主体结构,并进行张力数据采集发射、提升容器行程检测等程序设计,实现了对提升机钢丝绳张力的实时检测、记录功能。

大跨度后张拉缓粘结预应力结构施工质量控制

缓粘结预应力技术是有粘结、无粘结施工技术发展到一定阶段的创新,其施工工艺简单,质量容易控制,节点布置灵活,耐久性能优异,工程经济性强。但预应力专业施工单位一般规模不大,施工水平参差不齐,施工质量不易控制,因此,施工质量控制是缓粘结预应力施工的重点。

升船机钢丝绳-缓冲油缸防撞装置设计方法

钢丝绳-缓冲油缸防撞装置主要应用于过船规模较大的升船机工程中,目前关于该形式防撞装置设计方法的研究甚少,且存在一定局限性,直接影响防撞装置的布置和设计。基于船舶与防撞装置撞击过程中能量转换以及空间几何关系的分析,提出钢丝绳-缓冲油缸防撞装置设计计算方法,包括钢丝绳张力、船舶水平行进距离和油缸缓冲行程等重要参数的设计计算和控制条件的确定。通过设计计算结果与向家坝升船机钢丝绳-缓冲油缸防撞装置实船试验结果的比较,验证了本设计方法的安全性和合理性。提出的设计方法可为升船机钢丝绳-缓冲油缸防撞装置的设计和改造提供参考。

硅锭线切割张力控制方法对比研究

为满足低成本、低切损、高精度、高稳定性的硅片切割要求,在分析常用的两种线切割张力控制方法优缺点的基础上,采用ADAMS软件进行了弹簧式张力控制原理的建模与动力学仿真,并基于Simulink与MFAC控制算法对电控式张力控制进行了ADAMS与MATLAB动力学联合仿真。结果表明,两种张力控制方法所得到的电极丝加速度变化曲线走势一致,电控式张力控制在快速性及精确性方面优于弹簧式张力控制,但平稳性较差。进而,提出弹簧与电控相结合的张力控制方法,并在ADAMS中完成建模与动力学仿真。结果表明,该装置可在一定程度上取长补短。

预绞丝成型工艺研究与设备开发

预绞丝是特高压架空线路上的连接金具,能传递机械载荷、电气负荷以及保护电缆。预绞丝制造难点是成型张力不恒定,影响预绞丝尺寸精度,导致金具与电缆配合度降低,加剧磨损与松动,影响电气性能。从预绞丝成型工艺出发,对成型张力进行研究,分析成型条件,设计张力控制机构和系统;运用模糊神经网络算法对张力进行控制,研发出新型预绞丝成型设备并进行试验。试验结果符合控制技术指标,设备性能满足生产需求。

跨既有高速天桥拆除施工技术

按照当前现代交通业的发展进程,大多数涉及预应力钢筋混凝土构造物废除新建、扩容美化施工需求持续增长,预应力钢筋混凝土构造物废除或重建施工采用保守施工工法、机具面临施工条件复杂、安全风险极大、对外协调难度大、利润低等特点,而施工管理必须满足当地有关法律法规、最新规范及环水保要求。因此迫切需要新工艺解决预应力钢筋混凝土构造物废除遇到的各种难题。

Research of 1770 MPa galvanized steel wire for stay cable of domestic bridges

This paper focuses on introducing the manufacture technology of 1 770 MPa galvanized steel wires for stay cables applied to domestic bridges.During the development practices of high strength galvanized wire for stay cables used in Sutong Bridge,Baosteel has established three key technologies based on research of manufacture technology and technical innovation.The three key technologies are:"Double Tensioning + limiter die" process,"dominant process + fine adjustment" in integrated optimization technology and "three-level control" in hot dip galvanization.With these key technologies,Baosteel has produced 1 770 MPa galvanized wires for stay cable,which has high tensile strength,low relaxation and good torsion performances.

A Double Tension Band Technique for Patellar Fractures—A New Concept

Amongst the many known techniques used for the management of fractures of the patella, the tension band wire fixation is a reliable treatment modality and has given consistently good results. In transverse patellar fractures, a combination of cerclage wiring and tension band fixation gives a good mechanical stability and an environment conducive to healing. The fracture described herein is classified as 45-C1 (based on Orthopaedic Trauma Association classification) of the right knee of a forty three years old male patient. It was fixed with three vertical 1.5 mm K wires and double cerclage wire looped proximally through the quadriceps tendon and distally through the patellar ligament in a double figure-of-eight configuration. The average follow-up period was 7 months. The Activity of Daily Living Scale (ADLS) of the Knee Outcome Survey was used to assess symptoms and functional capability of the knee. The fracture union was achieved at an average of 10 weeks. Full range of knee motion was achieved by end of the third postoperative month. No complications, such as infection and implant failure were noted. The technique aims to stress the advantage of giving a balanced fixation addressing the bony elements (the fractured ends) as well as the soft tissue (the extensor apparatus).

智能牵引供电系统接触网状态监测技术及应用

智能牵引供电系统具有信息化、自动化和智能化的特点,接触网作为牵引供电系统的重要组成部分,承担着电力输送的艰巨任务。为防止由于热胀冷缩使补偿装置移动范围过大导致发生接触网断线等重大事故,基于深度学习理论和图像处理算法对补偿装置进行实时监控,设计了接触网断线智能监测系统,实现了对智能化牵引供电系统进行更加全面的数据实时监测,为不断调整和优化智能牵引供电系统提供技术支持。

两种方法治疗髌骨下极骨折的疗效比较

目的比较不锈钢缝线三维立体缝合逐级复位固定与克氏针钢丝捆扎“8”字张力带治疗髌骨下极骨折的疗效。方法将40例髌骨下极骨折患者按照固定方法不同分为观察组(采用不锈钢缝线三维立体缝合逐级复位固定治疗,20例)和对照组(采用克氏针钢丝捆扎“8”字张力带治疗,20例)。比较两组手术情况,采用Lysholm评分评定膝关节功能。结果患者均获得随访,时间8~15个月。手术时间观察组明显短于对照组(P<0.05)。两组骨折对位对线良好,关节面平整,均达解剖复位,切口均一期愈合。并发症发生率观察组明显低于对照组(P<0.05)。末次随访时,膝关节屈曲活动度观察组明显大于对照组(P<0.05),两组患者步态均无明显异常;采用Lysholm评分评定膝关节功能的优良率,观察组明显高于对照组(P<0.05)。结论与克氏针钢丝捆扎“8”字张力带相比,不锈钢缝线三维立体缝合逐级复位固定治疗髌骨下极骨折手术时间短、并发症发生率低,更利于患者膝关节功能的恢复。