股骨颈骨折内固定方法的比较与选择

目的探讨不同内固定方法在股骨颈骨折中的疗效.方法将4种不同内固定方法的治疗结果进行比较.结果固定方法的不同对骨折愈合率有明显差异,但对股骨头坏死率影响不大,股骨头坏死率高低取决于创伤时股骨头血运破坏的程度.结论空心钉操作简单,固定可靠,骨折的愈合率高,应做为股骨颈骨折手术的首选内固定材料.     

不同钉位布局影响股骨颈骨折内固定效应的生物力学研究

目的:观察应用多枚钉内固定治疗股骨颈骨折时采取不同钉位布局对骨折断端固定效应的影响,为临床操作中寻求最佳钉位布局奠定基础。方法:通过特制壮年人体尸骨股骨颈骨折模型,进行直视下解剖复位后,分别应用3钉倒三角形、3钉正三角形和双钉平行3种不同钉位布局内固定方法完成内固定。在生物力学万能试验机上进行轴向压缩和扭转实验,观察不同生物应力下断端相对的位移距离、轴向刚度、水平剪切刚度和扭转强度等项目,取得试验数据后经统计学处理,进行组间对比,观察其差异的显著性。结果:在3种钉位布局的内固定方法之中,以股骨矩核心下2～3mm处进钉位为下位顶点的倒三角形钉位布局能获得最坚强的固定效应,相同应力下其位移距离最小而各项刚度最大;而股骨矩核心上位和中下位双钉固定法固定效应最差,表现为相同应力下位移距离最大和各项刚度最小。结论:尽可能选择以股骨矩核心下2～3mm处进钉位为下位顶点的倒三角钉位布局法,尽可能减少应用双钉位布局法。     

股骨颈骨折预测的Ansys非线性屈曲分析

目的 实施10例股骨颈骨折的Ansys非线性屈曲分析,模拟与生物力学实验一致的股骨颈骨折实验全程.方法 采用10个股骨上段标本进行有限元建模,以十字坐标轴及绘图辅助软件TweakWindow实施精确的载荷施加及条件约束,进行特征值屈曲分析及非线性屈曲分析.结果 实现可控制的股骨颈骨折预测的Ansys非线性屈曲分析的载荷施加及条件约束;全部分析在达到结构崩溃时自动终止,发生股骨颈骨折的极限载荷为( 12 324.07±4439.733)N,最大位移为(7.6067 ±2.2716) mm,截取载荷-位移曲线;通过应力等值线图可判断股骨颈骨折位置.结论 非线性屈曲分析是一种适用于骨折预测的有限元算法;通过十字坐标轴及绘图辅助软件可以实现精确可控制的载荷施加及条件约束,实现与生物力学实验一致的条件设置.     

股骨颈合并同侧粗隆下骨折3种内固定方式的生物力学分析

目的比较股骨近端锁定板(PFLP)、加长型股骨近端防旋髓内钉(PFNA)、加长型股骨近端髓内钉(PFN)内固定股骨颈合并同侧粗隆下骨折的生物力学性能。方法将18根成年防腐人尸体股骨标本编号后通过随机数字表法随机分为3组,每组6根。制作成股骨颈完全无移位骨折,合并同侧股骨粗隆下内侧皮质缺损5 cm的骨折模型。依据标准技术分别予以PFLP、加长型PFNA、加长型PFN固定。在生物力学试验机上先后进行轴向压缩试验、扭转试验和轴向压缩破坏试验。结果加长型PFNA组轴向抗压刚度最高,为(130.61±5.51)N/mm;加长型PFN组其次,为(56.25±4.07)N/mm;PFLP组最低,为(3.59±2.52)N/mm;3组差异有统计学意义(F=2 337.77,P0.001)。PFLP组扭转刚度最高,为(1.30±0.23)Nm/°;加长型PFNA组其次,为(0.86±0.28)Nm/°;加长型PFN组最低,为(0.38±0.07)Nm/°;3组差异有统计学意义(F=106.05,P0.001)。加长型PFNA组破坏载荷最大,为(3 072.72±216.81)N;加长型PFN组其次,为(2 726.94±182.78)N;PFLP组最小,为(1 877.61±284.87)N;3组差异有统计学意义(F=138.31,P0.001)。结论内固定手术治疗股骨颈合并同侧粗隆下骨折时,加长型PFNA较PFLP、PFN具有生物力学优势。     

锁骨骨折内固定有限元分析的研究进展

锁骨骨折为常见的上肢骨折,由于其特殊解剖结构直接影响着肩关节的功能。锁骨骨折不同的损伤机制影响着内固定的力学效果,因此选择何种内固定方式一直困扰着骨科医生。有限元分析作为现代计算机力学软件分析,通过对锁骨骨折内固定的有限元分析,不仅能够了解骨折病因机制、内固定物的生物力学性能及骨折并发症等因素,还能为术前规划上提供指导意见,有利于术前规划并进行手术方式的个体化选择,有望成为锁骨骨折术前规划中不可缺少的一部分。该文就有限元分析在锁骨骨折的病因机制、相关影响因素、内固定的选择、术后并发症以及有限元分析过程中出现的问题进行综述。     

Biomechanical properties of off-axis screw in Pauwels III femoral neck fracture fixation: Bicortical screw construct is superior to unicortical screw construct

ObjectivesThe purpose of this study is to determine the biomechanical properties of the bicortical off-axis screw fixation for stabilizing of Pauwels III femoral neck fractures compared with other fixation methods.MethodsEighteen synthetic femurs (Sawbones Pacific Research Laboratories, Vashon, WA) were divided into three groups. The osteotomy was made vertically to mimic the Pauwels type III femoral neck fracture. Group A (n = 6) was fixed with traditional inverted triangle cannulated screws. Group B (n = 6) was fixed with a unicortical off-axis screw and two parallel cannulated screws. Group C (n = 6) was fixed with a bicortical off-axis screw and two parallel cannulated screws. Each group was tested with a nondestructive axial compression test at a 7° of valgus followed with 1000 cycles of cyclic loading test from 100 N to 1000 N. Finally, a destructive axial compression test was applied until catastrophic failure.ResultsThe average axial stiffness from group A to group C was 856.5, 934, and 1340 N/mm, respectively. The average ultimate failure load from group A to group C was 2612.7, 2508.8, and 3706 N, respectively. Group C exhibited significantly greater axial stiffness and a higher ultimate failure load than the other two groups (P < 0.05). Regarding the interfragmental displacement, the values from group A to group C were 0.41, 0.83, 0.36, respectively, and group B exhibited significantly larger fracture gap formation after the cyclic loading test.ConclusionsThe results of this biomechanical study show statistically significant increases in axial stiffness and ultimate failure load for the off-axis screw placed in bicortical fashion. Once the off-axis screw was positioned unicortically, the largest fracture diastasis was observed as compared to the other two methods.     

不同角度螺钉固定股骨颈骨折并发转子下骨折风险的生物力学分析

目的通过有限元方法对内收型股骨颈骨折的不同角度空心加压螺钉固定技术进行对比评价,判断何种技术更易发生转子下骨折,为临床应用提供理论依据。方法以内收型股骨颈骨折为研究对象建立有限元模型,模拟单腿站立时的受载和垂直力加载2种情况,对倒三角构型不同角度置钉技术分别进行有限元计算。结果第3模型在股骨干张力侧的最大Von-Mis-es应力明显高于其他模型,其他模型张力侧应力的差别都较小。结论倒三角构型时,单枚远钉低角度固定与传统高角度固定时发生转子下骨折的风险差别不大,只有三钉同时低角度固定时发生转子下骨折的可能性最大,建议临床避免低角度多钉固定。     

预防股骨颈骨折空心钉内固定术后股骨颈短缩空心螺纹钉优化选择的有限元分析

目的：运用有限元分析法比较采用不同数量全螺纹空心钉在不同置钉位置内固定治疗Pauwels Ⅱ型股骨颈骨折,预防术后颈短缩的生物力学特性。方法：选取健康老年女性志愿者1名,年龄55岁,体重70 kg,身高165 cm。采用CT扫描,获取右侧股骨数据,在三维建模软件分别建立PauwelsⅡ型股骨颈骨折模型、全螺纹空心钉和半螺纹空心钉模型。按全螺纹空心钉数量和置入呈倒三角分布位置分为8组骨折内固定模型：3枚半螺纹钉组、1枚前上方全螺纹钉加2枚半螺纹钉组,1枚后上方全螺纹钉加2枚半螺纹钉组,1枚下方全螺纹钉加2枚半螺纹钉组,1枚前上方半螺纹钉加2枚全螺纹钉组,1枚后上方半螺纹钉加2枚全螺纹钉组,1枚下方半螺纹钉加2枚全螺纹钉组,3枚全螺纹钉组。在有限元分析软件中分别加载同样载荷,比较分析各组的内固定物的应力分布及应力峰值、股骨近端应力分布及应力峰值、骨折断端切面的应力分布及应力峰值、内固定物位移峰值,并比较术后股骨颈长度。结果：各组的内固定应力主要集中于骨折线处,且均位于下方螺钉的底部,应力峰值分别为239.71、213.44、199.37、230.82、201.63、215.72、185.6...     

经皮鳞纹针固定治疗股骨颈骨折

1987年2月-2002年2月，我院采用经皮鳞纹针固定治疗股骨颈骨折112例，并对资料完整的病例进行回顾性总结，报告如下。     

四种方法固定股骨颈骨折的生物力学研究

目的探讨符合生物力学原理的股骨颈骨折的固定方法.方法比较了单纯斯氏针、加压螺纹钉、低角度和大角度穿针外固定支架四种固定股骨颈骨折的方法在不同载荷下的位移和旋转角度等.结果在抗压力方面,低角度外固定支架组优于其余各组(P＜0.01).在抗扭力方面,加压螺纹钉最差,其余各组无显著性差异.同样载荷下低角度进针组各针应变小于大角度进针组各针(P＜0.01).结论一枚加压螺纹钉的强度最差;三根斯氏针有一定的抗压及抗旋转性能;低角度穿入三枚斯氏针并通过外固定支架固定有着较强的抗压及抗旋转性能,为一种有效的固定方法;大角度穿针外固定支架固定断端间存在较大的剪力,不利于断端加压;穿针应沿压力骨小梁方向尽量贴紧股骨距低角度钻入才符合生物力学原理;三针在固定股骨颈中各起着相同的负重作用.     

老年人股骨转子间骨折三种内固定方法临床对比分析

目的探讨不同内固定方法治疗老年人股骨转子间骨折的疗效。方法对本院在2005年-2008年收治的57例股骨转子间骨折分别行动力髋螺钉（DHS）和股骨近端解剖锁定钢板和Gamma钉手术内固定治疗进行回顾性分析,并对三种手术方法在手术时间、术中出血量、术后引流量、骨折临床愈合时间、术后功能恢复程度和术后并发症进行比较。结果随访3个月～3年,57例股骨转子问骨折全部愈合,按Harris评分标准优良率达90％以上。结论DHS和解剖锁定钢板及Gamma钉适用于稳定型骨折,均具有固定牢固,手术操作简单,并发症少等优点。但对于不稳定型骨折．则Gamma钉内固定要优于DHS及解剖锁定钢板。     

Biomechanical evaluation of different internal fixation methods based on finite element analysis for Pauwels type III femoral neck fracture

Background and objectiveThe best internal fixation method for the treatment of Pauwels type III femoral neck fractures (FNFs) remains to be demonstrated. Through finite element analysis, this study explored whether dynamic hip screw (DHS) combined with anti rotation screw or medial buttress plate can improve the stability of internal fixation, and the femoral neck system (FNS) with similar structure to DHS and the traditional cannulated screw (CSs) were added for comparison. To evaluate their respective biomechanical advantages and disadvantages in the treatment of Pauwels type III FNFs.MethodsSix groups of internal fixation models for the treatment of FNFs were established, including CSs, DHS, DHS combined with single anti-rotation screw (DHS + SS), and DHS combined with both anti-rotation screw (DHS + BS), DHS combined with medial buttress plate (DHS + MBP), new femoral neck internal fixation system (Femoral Neck System, FNS). Four finite element analysis models were established for each group, evaluation of femoral displacement and internal fixation stress during stair climbing and walking conditions, and the contact force of the hip joint was used in two cases, dynamic and static.ResultsThe fracture plane motion and peak stress of internal fixators were the lowest with DHS + BS and CSs fixation, and the two results are very close, The peak value of DHS combined with anti rotation screw or medial buttress plate is much lower than that of DHS, indicating that the fixation effect of the combined model is enhanced, and there is no significant difference between FNS and DHS + SS.ConclusionBoth the anti rotation screw and medial buttress plate can effectively reduce the movement of fracture section and share the shear force of DHS, FNS has the similar fixation stability to DHS + SS, DHS + BS has the biomechanical advantages of significantly reducing the risk of internal fixation failure and femoral yield. Therefore, the use of DHS + BS may be a more favorable choice in the case of Pauwels type III FNFs with higher fixation requirements.     

Biomechanical comparison of four different posterior malleolus fixation techniques: A finite element analysis

PurposeThe objective of this study was to compare the biomechanical behavior of four fixation methods for posterior malleolar fracture (PMF) by finite element analysis (FEM).MethodsFour internal fixation techniques used for fixation of PMF were assessed by FEM - a computational study: posterior one-third tubular 3.5 mm buttress plate (PP) with one screw (PP 1 screw), PP with two screws (PP 2 screws), two cannulated 3.5 mm lag screws in the antero-posterior (AP) direction (AP lag screws), and two postero-anterior (PA) cannulated 3.5 mm lag screws (PA lag screws). PMF with 30% and 50% fragment sizes were simulated through computational processing reconstructed from computed tomography (CT). The simulated loads of 700 N and 1500 N were applied to the proximal tibial end. The FEM evaluated the total and localized displacements of the PMF. For the analysis of stresses, the variables maximum principal (traction) and minimum principal (compression) were used. For the metallic implants, the equivalent von Mises stress (VMS) was used.ResultsPA lag screw showed the lowest values for total and localized displacement, minimum and maximum total stress, and VMS in both physiological conditions and sizes of posterior malleolus involvement. The localized displacement was statistically lower for lag screws compared to PP techniques at 700 N (p < 0.05) and 1200 N (p < 0.05). The maximum total stress was statistically lower for PA lag screws compared to PP 1 fixation with 700 N (p = 0.03) and 1200 N (p = 0.039).ConclusionPA lag screws yield better results in terms of total and localized displacement, minimum and maximum total stress, and VMS in both physiological conditions and sizes of posterior malleolus involvement. These results demonstrate that PA lag screws are biomechanically the most efficient technique for the fixation of PMF.     

股骨颈膨胀式带锁加压钉的研制及生物力学评价

目的 探讨股骨颈骨折内固定的方法，评价HZS型股骨颈膨胀式带锁加压钉(interlocking expanding compressive screw,IECS)的生物力学性能。方法 根据股骨颈骨折特殊的生物力学特性，设计制作由主钉、股骨头分叉钉、分叉钉推进螺帽、加压螺帽匀力垫、加压螺帽、斜向锁钉和主钉尾帽构成的股骨颈膨胀式带锁加压钉，以单枚双头加压螺钉(dynamic compressive screw,DCS)、双头加压子母螺钉(twin compressive screur，2CS)和三枚空心加压螺钉(three cannulated screws,3CS)作对照组进行生物力学实验。结果 IECS固定的股骨颈骨折在位移、轴向和水平剪切刚度、扭转强度和刚度、极限载荷等生物力学性能均明显优越于DCS、2CS和3CS。结论 IECS能有效对抗骨折断端间的分离、扭转、剪切、张应力和压应力。结构轻巧，操作简便，安全可靠。     

Biomechanical evaluation of the expansive cannulated screw for fixation of femoral neck fractures

Background

Femoral neck fracture is one of the common clinical traumas, especially amongst elder patients. This study aims to test, compare and evaluate the bone-screw interface strengths, the fatigue strengths, and the stabilities of our newly designed expansive cannulated screw (ECS) and the common cannulated compression screw (CCS) in the fixation of femoral neck fracture, which is a summary of recent research.

Methods

Twenty-four pairs (48) of fresh femur specimens were randomly divided into four groups with six pairs (12) in each. To simulate one-legged standing, the maximum compressive strength and the single-screw axial pull-out force were compared between the fixed femoral necks treated with two ECSs and two CCSs, two ECSs and three CCSs or three ECSs and three CCSs, respectively. The screws were also subjected to 1 000 000 cycles of a loaded fatigue test and the results were recorded.

Findings

When the same number of screws was used, the ECS showed significantly greater maximum compressive strength than the CCS (P < 0.05), but no significant difference in fixation effectiveness was detected between the two ECSs and the three CCSs groups. The maximum axial pull-out strength of the ECS was also significantly greater that of the CCS (P < 0.01); however, there was no sign of fatigue in both the ECS and CCS after 1 000 000 cycles of loaded fatigue test.

Interpretation

The ECS shows better fixation performance than the currently and commonly used CCS; under certain circumstances, fixation with two ECSs can achieve the same effect as that with traditional three CCSs.     

多枚空心加压螺纹钉治疗股骨颈骨折

目的：探讨多枚空心加压螺纹钉治疗股骨颈骨折及如何减少并发症。方法：用多枚空心加压螺纹钉治疗股骨颈骨折68例。对治疗后疼痛、生活能力、关节活动度及行走情况进行比较，观察分析临床疗效。结果：随访2－5年，优：42例；良：19例；可：5例；差：2例。结论：在治疗股骨颈骨折的过程中，解剖复位，坚强内固定和晚期负重至关重要。     

老年人股骨颈骨折内固定治疗的研究进展

内固定治疗老年人股骨颈骨折,尤其空心钉的应用,较髋关节置换具有微创、经济、操作简便的优势,成为近年来骨科临床研究的热点.空心钉的构型问题仍存在争议,大多数临床医生认为3枚空心钉平行置入的倒三角构型固定方法在生物力学及临床效果方面优于正三角构型,而非平行的强斜置钉技术能使螺钉分担更多体重,减少术后并发症,更适用于老年骨质疏松患者.内固定治疗股骨颈骨折术后骨不连、股骨颈短缩等难题仍是国内外学者关注的焦点.如何把握内固定手术的适应证,了解并发症的相关因素,预防并发症的发生有待进一步探索.     

中年人移位型股骨颈骨折内固定与关节置换的疗效比较

目的：分析比较年龄55～65岁中年人股骨颈移位型骨折内固定与关节置换的临床疗效。方法 ：2016年9月至2020年8月收治GardenⅢ型或Ⅳ型股骨颈骨折患者86例,根据手术方式的不同将其分为两组。其中38例采用平行拉力螺钉内固定治疗（内固定组）,男26例,女12例,年龄55～64(60.2±3.1)岁;48例进行全髋关节置换术（关节置换组）,男28例,女20例,年龄57～65(61.3±3.8)岁。受伤至手术时间1～3 d。比较两组患者的再手术率,深部感染发生率,髋关节功能Harris评分,疼痛视觉模拟评分（visual analogue scale,VAS）,患者主观报告功能评分采用欧洲五维健康量表（European five-dimensional Health Questionnaire,EQ-5D）。结果：所有患者获得随访,时间24～54(35.8±10.3)个月。平行拉力螺钉内固定组术后再手术率高于较全髋关节置换术组（P<0.05）。两组患者深部感染发生率比较,差异无统计学意义（P>0.05）。两组患者术后12个月时髋关节Harris评分及VAS比较,差异均无统...     

空心螺钉结合带旋股外侧动脉升支髂骨瓣与单纯空心螺钉内固定治疗青壮年股骨颈骨折的疗效比较

目的比较空心螺钉结合带旋股外侧动脉升支髂骨瓣与单纯空心螺钉内固定治疗青壮年股骨颈骨折的疗效。方法采用两种术式治疗股骨颈骨折78例。其中采用2枚空心螺钉内固定结合旋股外侧动脉升支髂骨瓣治疗40例(A组),单纯采用3枚空心螺钉内固定治疗38例(B组)。结果 78例均获3～9年随访。A组未见骨折不愈合病例,B组2例骨折不愈合,A组平均愈合时间(90.3±3)d,B组平均愈合时间(150.3±25)d。A组1例股骨头坏死,B组5例出现股骨头缺血坏死。两组末次随访时Harris评分比较差异无统计学意义(P>0.05)。结论应用2枚空心螺钉内固定结合带旋股外侧动脉升支髂骨瓣治疗青壮年股骨颈骨折具有再次手术率低,骨折不愈合率及骨坏死发生率低的优点。     

空心钉直径与股骨颈骨折愈合的相关性研究

目的分析选用直径8 mm的史塞克空心钉内固定治疗不同股骨头颈部直径的股骨颈骨折的临床疗效。方法回顾性分析自2008-06—2013-06采用直径8 mm空心钉内固定治疗69例股骨颈骨折,根据股骨颈头颈部直径分为观察组(30~40 mm)和对照组(40~50 mm)。结果观察组股骨颈头颈部直径大于对照组,2组比较差异有统计学意义(t=6.383,P=0.015)。2组骨折均愈合,骨折愈合时间比较差异无统计学意义(P0.05)。观察组优良率94.8%,对照组优良率93.3%,2组优良率比较差异无统计学意义(t=0.355,P=0.552)。结论本研究结果显示,排除患者自身因素,以8 mm空心钉内固定治疗不同股骨颈头颈部直径的股骨颈骨折时并不会影响骨折愈合率及愈合的时间。该研究结果可能有助于节省治疗费用,同时也表明手术中试图获得空心钉与股骨颈宽度的"良好匹配"并不一定会带来良好的临床疗效。