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.

Near resonance vibration isolation on a levered-dual response(LEDAR)Coulomb-damped system by differential preloads/offsets in linear springs

The levered-dual response(LEDAR)Coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear springs.It takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration isolation.The isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without guiderails.The compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential threshold.The isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate connector.The observed near resonant isolation thus makes the LEDAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

High-Quality and Wafer-Scale Cubic Silicon Carbide Single Crystals

Cubic silicon carbide(3C-SiC)has superior mobility and thermal conduction over that of widely applied hexagonal 4H-SiC.Moreover,much lower concentration of interfacial traps between insulating oxide gate and 3C-SiC helps fabricate reliable and long-life devices like metal-oxidesemiconductor field effect transistors.However,the growth of high-quality and wafer-scale 3C-SiC crystals has remained a big challenge up to now despite decades-long efforts by researchers because of its easy transformation into other polytypes during growth,limiting the development of 3C-SiC-based devices.Herein,we report that 3C-SiC can be made thermodynamically favored from nucleation to growth on a 4H-SiC substrate by top-seeded solution growth technique,beyond what is expected by classical nucleation theory.This enables the steady growth of high-quality and large-size 3C-SiC crystals(2-4-inch in diameter and 4.0-10.0 mm in thickness)sustainable.The as-grown 3C-SiC crystals are free of other polytypes and have high-crystalline quality.Our findings broaden the mechanism of hetero-seed crystal growth and provide a feasible route to mass production of 3C-SiC crystals,offering new opportunities to develop power electronic devices potentially with better performances than those based on 4H-SiC.

DEFORMATION LOCALIZATION AND SHEAR BAND FRACTURE IN STRONG ANISOTROPY SHEET TENSION

The tensile deformation localization and the shear band fracture behaviors of sheet metals with strong anisotropy are numerically simulated by using Updating Lagrange finite element method, Quasi-how plastic constitutive theory([1]) and B-L planar anisotropy yield criterion([2]). Simulated results are compared with experimental ones. Very good consistence is obtained between numerical and experimental results. The relationship between the anisotropy coefficient R and the shear band angle theta is found.

Tuning of band gaps for a two-dimensional piezoelectric phononic crystal with a rectangular lattice

In this paper, the elastic wave propagation in a two-dimensional piezoelectric phononic crystal is studied by considering the mechanic-electric coupling. The generalized eigenvalue equation is obtained by the relation of the mechanic and electric fields as well as the Bloch-Floquet theorem. The band structures of both the in-plane and anti-plane modes are calculated for a rectangular lattice by the planewave expansion method. The effects of the lattice constant ratio and the piezoelectricity with different filling fractions are analyzed. The results show that the largest gap width is not always obtained for a square lattice. In some situations, a rectangular lattice may generate larger gaps. The band gap characteristics are influenced obviously by the piezoelectricity with the larger lattice constant ratios and the filling fractions.

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).

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。

Band Gap Opening of Graphene by Noncovalent π-π Interaction with Porphyrins

Graphene has been recognized as a promising 2D material with many new properties. However, pristine graphene is gapless which hinders its direct application towards graphene-based semiconducting devices. Recently, various ways have been proposed to overcome this problem. In this study, we report a robust method to open a gap in graphene via noncovalent functionalization with porphyrin molecules. Two type of porphyrins, namely, iron protoporphyrin (FePP) and zinc protoporphryin (ZnPP) were independently physisorbed on graphene grown on nickel by chemical vapour deposition (CVD) resulting in a bandgap opening in graphene. Using a statistical analysis of scanning tunneling spectroscopy (STS) measurements, we demonstrated that the magnitude of the band gap depends on the type of deposited porphyrin molecule.The π-π stacking of FePP on graphene yielded a considerably larger band gap value (0.45 eV) than physisorbed ZnPP (0.23 eV). We proposed that the origin of different band gap value is governed due to the metallic character of the respective porphyrin.

ASTM E1268-19带状组织评定方法研究

介绍了美标ASTM E1268-19显微组织带状物级别或取向度的评级方法。采用ASTM E1268-19与GB/T13299—91试验方法,评定了热轧板卷试样的珠光体带状组织,并对ASTM E1268标准方法中检测视场的影响因素进行了分析。结果表明:增加检测视场数有利于提高定量评定结果的准确度;对于带状严重的组织,因其平行测量线容易全部落入单相组织内部或外部,对带状等级BR(banding rate)值的测量结果影响较大,针对此类情况,有必要增加检测视场数或测量线的数量,以提高BR的检测精度。

The Dust Comportment in the Latitudinal Band 10°North - 20°North in Africa: Emission and Deposition

The three measurement periods: the TOMS Nimbus-7 TOMSN7L3 v008 from 1978 to 1993, the TOMS EP TOMSEPL3 v008 from 1996 to 2005 and the OMI OMTO3d v003 from 2004 to 2008 have allowed the presence of dust to be observed in the 10&#176;North to 20&#176;North latitudinal band (10 - 20 band) of Africa. The 10 - 20 band has a permanent dust presence. The AERONET data show AOD peaks exceeding 2 in Senegal and Niger (on an AOD scale). The statistical study reveals intra-annual relationships in deposition. In Senegal, a significant deposition is observed.

A Narrow Band Chandra X-ray Analysis of SNR 3C 391

We present narrow-band and equivalent width （EW） images of the thermal composite supernova remnant （SNR） 3C 391 in the X-ray emission lines of Mg, Si and S using the Chandra ACIS Observational data. The EW images reveal the spatial distribution of the emission of the metal species Mg, Si and S in the remnant. They have a clumpy structure similar to that seen in the broadband diffuse emission, suggesting that they are largely of interstellar origin. We find an interesting finger-like feature protruding outside the southwestern radio border of the remnant, somewhat similar to the jet-like Si structure found in the famous SNR Cas A. This feature may possibly be the debris of the jet of ejecta from an asymmetrical supernova explosion of a massive progenitor star.

Clinical study of polydloxanone suture tension band fixation for treatment of patellar fractures

To explore biomechanic characteristics and clinical outcome of absorbable polydloxanone (PDS) treating patellar fractures.Methods The tensile strength test of PDS 0-0 or PDS 1-0 sutures were made in WDW305 electro-universal tester.A total of 60 cases were classified randomly and equally into two groups:treatment group (treated with the absorbable PDS tension hand) and Kirschner wire metals tension band control group (control group).Anatomy reduction was performed with towel clip fixation during operation.Treatment group was managed with diameter 1.5 mm Kirschner wires drilling two pores on the near or distal segment of patellar fracture end are penetrating through two strands of absorbable PDS 0-0 or PDS 1-0 sutures for a satisfactory fracture fixation.Control group was treated with Kirschner wires (2.0 mm in diameter) and steel wire (1.0 mm in diameter) of type “8” tension band fixation.Results Tensile strength testing showed that the biggest tensile of a strand PDS 0-0 sutures was 71.50 N and that of PDS 1-0 97.48 N,when the length was three times more than the initial.Two groups were followed up and the mean fracture healing time was two months,without broken wire or dislocation.Treatment group showed excellent clinical results in 21 cases,good in six and fair in three;while control group showed excellent clinical results in 19 cases,good in seven and fair in four,with no statistical difference compared with treatment group (χ2=0.32,P>0.05).Conclusion Absorbable PDS tension band has better characteristics of mechanics and creepage in treating patellar fractures.It can avoid defects of secondary operation and complications like needle-tail pain and sharped skin resulted from metal tension band fixation.Meanwhile,it is economic and worthy of further clinical application.16 refs,4 figs.

High Strain Rate Induced Plasticity-increasing of Metallic Materials under Tension

The effect of strain rate on plasticity has been Investigat-ed for three metallic materials with dynamic tension tech-nique. A phenomenon of high strain induced plasticity -increasing was found for tested materials. The elongation of quenched 30CrMnSiNi2A is 14. 5% under 40 m/s loading rate which is more than two times of the 7 % un-der 0. 5 mm/min. This typic high strain rate induced plasticity - Increasing phenomenon is associated with adiabatic heating, strain twinning and suppression of strain - induced - phase transformation.

张力带系统治疗髌骨骨折术后并发症分析及预防

髌骨骨折严重破坏了伸膝装置的连续性,影响膝关节屈伸功能。面对罹患人群和骨折形态的演变,髌骨骨折现有治疗技术的缺陷逐渐突显,非手术治疗很可能影响膝关节的正常活动。手术治疗被广泛接受,但往往伴随一些并发症,尤以临床最常用的张力带技术,其术后并发症日渐突出及明确。本文基于髌骨解剖结构及生物力学特征,通过临床观察及文献查阅,就张力带系统治疗髌骨骨折术后并发症、产生原因及预防措施进行综述。

Cable-pin系统与克氏针张力带治疗髌骨骨折的疗效比较

目的探讨Cable-pin系统与克氏针张力带在治疗髌骨骨折方面的临床效果。方法选取2010年2月至2015年1月在骨科就诊的67例髌骨骨折患者,均为闭合性髌骨骨折。其中观察组33例给予Cable-pin系统固定,对照组34例给予克氏针张力带固定,比较两组患者手术时间,术中出血量,开始负重时间,骨折平均愈合时间,术后3、6个月膝关节屈曲活动度,并发症发生率及治疗效果。结果观察组患者在骨折平均愈合时间、开始负重时间、术后3个月的膝关节屈曲活动度、术后并发症发生率、改良Bostman髌骨评分及疗效方面均优于对照组,差异均有统计学意义(均P<0.05);但观察组在手术时间、术中出血量及术后6个月膝关节屈曲活动度方面与对照组比较,差异均无统计学意义(均P>0.05)。结论应用Cable-pin系统相比于克氏针张力带在治疗髌骨骨折方面,具有操作简单、固定可靠、骨折愈合快、负重时间早、膝关节功能好及并发症少的优点,是一种理想的内固定方法。

Kirschner wire和Cable-pin在髌骨骨折手术治疗中的临床效果分析

目的分析比较Kirschner wire和Cable-pin在髌骨骨折治疗中的临床效果和应用价值。方法回顾2006年12月～2009年12月间笔者医院收治的107例髌骨骨折病人,分别用Kirschner wire和Cable-pin手术治疗68例和39例,记录两组病人的骨折类型、手术历时、术中出血量、住院日、医疗费用、术后并发症及远期膝关节功能恢复情况,应用SPSS11.0软件对观察指标进行统计学分析。结果 107例病人全部获得随访,随访时间为3～21个月,平均14.2个月。Cable-pin治疗组患者的手术历时和术中出血量均明显少于Kirschner wire治疗组(P<0.05),但医疗费用远高于后者(P<0.01)。两组病人术后并发症、住院日、骨折愈合时间和远期膝关节功能恢复情况无统计学差异。结论应用Kirschner wire手术治疗髌骨骨折更为广泛,方法灵活且疗效肯定,是一种性价比较高的治疗方法;Cable-pin操作简单、疗效可靠,但仅适用于横断性髌骨骨折,且医疗费用昂贵,在临床应用中有一定局限性。

Cu-Ni-Al形状记忆合金形变、相变以及裂纹形核的相互关系

采用金相显微镜和扫描电镜原位拉伸技术研究了Ｃｕ－Ｎｉ－Ａｌ形状记忆合金中的马氏体形变、马氏体相变以及微裂纹形核三者之间的关系．结果表明，拉伸时缺口前方首先形成可逆变的马氏体而不出现滑移带，微裂纹沿马氏体和母相界面形核．只有当裂纹扩展一段距离且应力集中足够大后，才有可能出现形变带。

钛针-钛缆张力带与锁定钢板螺钉治疗尺骨鹰嘴骨折的比较

目的比较钛针-钛缆张力带与锁定钢板螺钉治疗尺骨鹰嘴骨折的疗效。方法将47例尺骨鹰嘴骨折患者按固定方式的不同分为A组(采用钛针-钛缆张力带治疗,15例)和B组(采用锁定钢板螺钉治疗,32例)。比较两组切口长度、术中出血量、手术时间、术后住院时间、并发症情况。术后12个月采用Mayo肘关节功能评分、肘关节活动度评价肘关节恢复情况。结果患者均获得随访,时间12~14个月。手术时间B组明显长于A组(P<0.01);切口长度、术中出血量、术后住院时间两组比较差异均无统计学意义(P>0.05)。两组均无切口感染、不愈合等并发症发生。术后12个月,A组出现1例骨折不愈合;两组均无骨化性肌炎、创伤性关节炎等严重并发症发生;Mayo肘关节功能评分、肘关节活动度两组比较差异均无统计学意义(P>0.05)。结论钛针-钛缆张力带和锁定钢板螺钉均可以有效治疗尺骨鹰嘴骨折,但钛针-钛缆张力带内固定可缩短手术时间,降低手术感染风险,更利于患者康复。

翼外肌-髁突解剖复位内固定治疗髁突骨折的探讨

目的:探讨髁突骨折进行解剖复位和小型钛板坚强内固定的手术适应证、方法和治疗效果。方法:以髁头脱位骨折、髁颈和髁颈下骨折移位角度大于30°～45°、下颌支垂直高度降低超过4～5mm为适应证,对收治的23例28侧髁突骨折患者采用改良耳颞部"拐杖"型切口或颌后进路,行翼外肌-髁突解剖复位及张力带小型钛板坚强内固定。术后3～6个月复诊,检查面型、开口度、开口型、咬合关系、咀嚼力,并以此进行疗效评价。结果:所有患者面型对称,开口度较术前明显增大,开口型显著改变。2例术后错牙合患者经1周颌间牵引,恢复正常。影象学检查示髁突无移位,骨折无错位。钛板无移位,髁突表面无明显吸收现象。患者咀嚼有力。2例面瘫患者经治疗后3个月恢复。结论:选择合适病例,进行翼外肌-髁突开放性解剖复位固定,是一种既能恢复解剖形态又能恢复咀嚼功能的有效方法。

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。