寰椎后路单或双层皮质骨螺钉固定强度的生物力学评价

目的:测量单层皮质骨和双层皮质骨寰椎侧块螺钉固定与寰椎椎弓根螺钉固定的强度,为临床选择寰椎后路螺钉固定的方式提供生物力学依据。方法:利用12例新鲜的寰椎和第三颈椎标本,进行单层皮质骨和双层皮质骨的椎弓根螺钉或侧块螺钉固定,测试并比较其螺钉拔出强度。结果:双层皮质骨寰椎椎弓根螺钉固定的拔出力最大,为1757.0±318.7N;单层皮质骨寰椎椎弓根螺钉固定(1192.5±172.6N)与双层皮质骨寰椎侧块螺钉固定(1243.8±350.0N)及单层皮质骨C3椎弓根螺钉固定(1121.6±224.6N)的拔出力之间均无明显差异。结论:应用寰椎侧块螺钉固定时宜选用双层皮质骨螺钉固定,而寰椎椎弓根螺钉固定选用单层皮质骨螺钉即可。     

下颈椎经关节螺钉和Magerl侧块螺钉与脊神经关系的解剖学比较

目的对比下颈椎经关节螺钉和Magerl侧块螺钉固定技术神经根(前支和后支)损伤的潜在风险。方法应用经关节螺钉和Magerl侧块螺钉两种固定技术,固定C_(3-7)节段,每种技术使用2具标本和20枚螺钉。使用直径为3．5mm、长度为20mm的螺钉进行过度穿透侧块腹侧皮质固定。仔细解剖颈部的前侧方,观察螺钉与脊神经前、后支的关系。结果下颈椎经关节螺钉固定技术总体神经损伤比例(45%)明显低于Magerl侧块螺钉固定技术(90%),两者差异有显著性意义(P＜0．05)。经关节螺钉和Magerl侧块螺钉固定技术引起的神经损伤均最多见于脊神经后支,分别为25%和45%。结论经关节螺钉固定技术神经根损伤的风险低于Magerl侧块螺钉固定技术。     

腰椎皮质骨螺钉联合椎弓根螺钉固定对融合节段应力影响的有限元分析

目的:应用三维有限元法分析腰椎皮质骨螺钉(cortical bone trajectory screw,CBTS)联合椎弓根螺钉(pedicle screw,PS)固定对融合节段应力的影响.方法:采集1例正常成年人腰椎三维重建CT数据,应用三维有限元方法建立L3/4节段PS固定(A组)、CBTS固定(B组)和联合固定(...     

LCP“动力化”一折端微动及应力的有限元分析

[目的]通过三维有限元分析骨折断端微动及应力情况,为LCP(locking compression plates,LCP)"动力化"临床相关应用提供理论依据。[方法]建立骨折近端锁定孔锁定螺钉,远端全锁定螺钉固定(A组);骨折近端锁定孔普通螺钉,远端全锁定螺钉固定(B组);骨折近端加压孔普通螺钉,远端全锁定螺钉(C组)固定胫骨中下段横形骨折的有限元模型,各组分别予以1/6、2/6、3/6、4/6、5/6及1倍体重应力值进行轴向压缩实验,评价各组骨折断端轴向微动距离、胫骨及内固定最大应力以及断端应力值等指标。[结果]相同轴向应力载荷下,胫骨最大应力:AB>C;骨折端轴向微动位移:A相似文献   

膨胀螺钉固定重建前交叉韧带的生物力学研究

背景:关节镜下重建前交叉韧带(ACL)的方法很多,且疗效较好。但目前尚无有关固定方法是否能提供坚强固定、恢复原有ACL生物力学特性的相关研究。目的:探讨股骨端膨胀界面螺钉固定腘绳肌腱移植重建ACL的生物力学。方法:取新鲜冰冻成人膝关节标本21具,采用4股腘绳肌腱移植重建ACL,股骨端分别使用膨胀界面螺钉(n=7)、可吸收界面螺钉(n=7)、金属界面螺钉(n=7)固定,测试循环载荷后位移、100 N位移、400 N位移、抗拉刚度、最大拔出载荷、失败模式以及肌腱切割程度等,并进行统计学分析。结果:循环载荷后位移:可吸收螺钉组<金属螺钉组<膨胀螺钉组,无统计学差异(P>0.05);最大拔出载荷:膨胀螺钉组>可吸收螺钉组>金属螺钉组,膨胀螺钉组与可吸收螺钉组比较无统计学差异(P>0.05),膨胀螺钉组与金属螺钉组比较有统计学差异(P<0.05);肌腱切割程度:膨胀螺钉切割伤最轻,可吸收螺钉次之,金属螺钉最重。结论:膨胀界面螺钉的最大拔出载荷、100 N位移、400 N位移以及抗拉刚度均超过普通界面螺钉,对移植肌腱损伤小,可以满足肌腱重建固定ACL的需要,并可实现单隧道ACL双束解剖重建。     

磷酸钙骨水泥强化椎弓根螺钉固定的生物力学研究

目的:评价磷酸钙骨水泥(calciumphosphatecement,CPC)对椎弓根螺钉固定的强化作用。方法:在两组男性尸体椎骨的一侧直接置入椎弓根螺钉作为对照(对照侧),另一侧填入CPC后再置入螺钉作强化固定(强化侧),15min和12h后测定椎弓根螺钉的最大轴向拔出力(Fmax),然后用CPC重新固定12h后拔松的椎弓根螺钉并测得其Fmax。结果:强化侧Fmax和对照侧比较,15min后提高了55%,12h后提高了83%;重新固定后,两侧Fmax较固定前分别提高了54.2%和63.6%,差别有显著性意义(Wilcoxon's检验,P<0.01)。结论:磷酸钙骨水泥能强化椎弓根螺钉的固定。     

枢椎椎板螺钉与椎弓根螺钉抗拔出强度的比较

目的:比较枢椎椎板螺钉与枢椎椎弓根螺钉的抗拔出强度,为临床应用枢椎椎板螺钉固定提供生物力学依据。方法:在7具成年男性新鲜尸体枢椎标本上进行枢椎单皮质椎弓根螺钉和双皮质椎板螺钉固定,测试螺钉拔出力。结果:单皮质枢椎椎弓根螺钉的最大拔出力平均为875.3±403.2N,双皮质枢椎椎板螺钉的最大拔出力平均为679.5±308.2N;椎弓根螺钉的最大拔出力大于椎板螺钉,但二者之间无统计学差异。结论:枢椎椎板螺钉进行双皮质固定具有可靠的力学固定强度,可作为枢椎椎弓根螺钉的补充固定技术。     

动力髋螺钉结合防旋螺钉内固定治疗中老年股骨颈骨折疗效分析

目的分析采用颈骨折动力髋螺钉结合防旋螺钉内固定治疗中老年股骨颈骨折的效果。方法对47例中老年股骨颈骨折患者行闭合复位动力髋螺钉加防旋螺钉治疗。结果本组手术时间(46.02±14.60)min,术中出血量(110.20±14.34)m L。骨折愈合45例(95.74%),骨折愈合时间(5.21±0.58)个月。随访12个月,1例患者出现拉力螺旋钉切除骨头,1例在内固定取出后出现股骨头塌陷。无其他并发症发生。依据髋关节Harris评分:本组优良率为91.48%(43/47)。结论采用动力髋螺钉结合防旋螺钉内固定治疗中老年股骨颈骨折,固定牢固,并发症发生率低,功能恢复优良率高。     

可吸收螺钉和加压空心螺钉治疗Jones骨折的比较

目的探讨加压空心螺钉与可吸收螺钉微创内固定治疗Jones骨折的临床疗效,为该类骨折的处理提供参考。方法按标准纳入2013年6月至2014年12月连续收治的27例Jones骨折患者,根据内固定修复方式不同分为两组,其中加压空心螺钉组15例,可吸收螺钉组12例。对比两组患者的骨折愈合时间、AOFAS评分、内固定术后骨折移位和感染例数,评估疗效。结果 27例获得6~22个月,平均(12.1±4.8)个月的随访。加压空心螺钉组有1例患者术后1个月复查X线片时发现骨折移位(为骨折较为粉碎者),可吸收螺钉组发生螺钉断裂2例,并均出现断钉后骨折移位,所有3例骨折移位患者经支具固定、制动后骨折延迟愈合,其余患者均顺利愈合。加压空心螺钉组平均愈合时间为(8.3±1.5)周,可吸收螺钉组平均愈合时间为(8.9±1.6)周,差异无统计学意义(P0.05)。内固定12周后,参照AOFAS的中前足评分标准,加压空心螺钉组评分平均(87.6±12.8)分,优良率为93.3%;可吸收螺钉组评分平均(82.0±11.4)分,优良率为83.3%;两组的AOFAS平均评分差异无统计学意义(P0.05)。结论对于Jones骨折患者,加压空心螺钉与可吸收螺钉内固定治疗均可获得满意疗效,采用可吸收螺钉内固定的患者,应适度延迟下地负重的时间。     

两种长度的颈椎椎弓根螺钉与侧块螺钉拔出试验比较

目的:比较两种长度的颈椎椎弓根螺钉和侧块螺钉的抗拔出力,探讨颈椎经椎弓根短螺钉固定的可行性。方法:5具C3~C5共15节新鲜颈椎标本,用长度为28mm和20mm的皮质骨螺钉分别置入椎弓根,并用20mm的螺钉行侧块双皮质固定,螺钉进入侧块深度约14mm。行拔出试验,比较螺钉的最大轴向拔出力。结果:椎弓根长螺钉的最大拔出力为650N,椎弓根短螺钉为585N,两者比较无显著性差异(P>0.01);侧块螺钉的最大拔出力为360N,与椎弓根短螺钉比较有显著性差异(P<0.0001)。结论:颈椎椎弓根短螺钉固定可提供足够的稳定性,其安全性相对较高。     

陈旧性舟骨骨折的手术疗效分析

目的 探讨陈旧性舟骨骨折的治疗方法及临床疗效.方法 2005年6月至2008年6月,对16例陈旧性舟骨腰部骨折患者,采用腕关节背侧入路,去除骨折处硬化骨后加自体骨植骨,并用Herbert螺钉加克氏针进行固定.术后定期复查X线片,观察骨折愈合情况.根据Krimmer评分评估腕关节功能.结果 术后16例获得随访(平均为8.5个月),所有骨折均获得愈合,平均愈合时间为16周.按Krimmer评分:优8例,良5例,可2例,差1例;优良率达81.3%.结论 对于陈旧性舟骨骨折,通过自体骨植骨及Herbert钉加克氏针内固定,能取得较理想的临床效果.

Abstract：

Objective To discuss the surgical methods and treatment effects of old scaphoid fractures.Methods From June 2005 to June 2008, 16 cases of old scaphoid waist fractures were treated by debridement of necrotic bone, autologous bone graft and Herbert screw plus Kirschner wire internal fixation through a dorsal approach. Postoperative X-rays were taken on a regular basis to observe fracture healing. Wrist function was evaluated according to Krimmer score. Results Postoperatively the 16 cases were follow-up for an average of 8.5 months. All the fractures healed and the average healing time was 16 weeks. Krimmer score determined wrist function to be excellent in 8 cases, good in 5 cases, fair in 2 cases and poor in 1 case. The overall satisfactory rate was 81.3%. Conclusion Herbert screw and K-wire internal fixation combined with autologous bone graft can attain good clinical results in the treatment of old scaphoid fiactures at the waist.     

闭合复位经皮Herbert螺钉内固定治疗新鲜稳定型舟骨腰部骨折

目的：观察闭合复位经皮Herbert螺钉内固定治疗新鲜稳定型舟骨腰部骨折的临床疗效。方法对采用闭合复位经皮Herbert螺钉内固定治疗的12例新鲜稳定型舟骨腰部骨折患者进行随访,采用修订后Mayo腕关节评分标准对临床效果进行评价。结果所有患者均获得随访,随访时间13~23个月（平均15个月）,无感染、螺钉松动、过敏排斥反应及关节炎的发生。所有患者骨折均愈合,骨折愈合时间为8~14周,平均10周。按修订后Mayo腕关节评分标准：优7例,良4例,可1例,优良率91.7%。结论闭合复位经皮Herbert螺钉内固定治疗新鲜稳定型舟骨腰部骨折,具有操作简单,固定可靠,并发症少及能早期进行功能锻炼等优点。     

手术治疗舟骨骨折49例结果及体会

目的报道手术治疗49例舟骨骨折的结果及体会。方法经皮或切开复位Acutrak钉/空心钉/可吸收钉/U形钉内固定舟骨骨折,陈旧性骨折及骨坏死者加做带血管蒂桡骨茎突骨瓣移植,记录术后骨折愈合时间、握力、腕关节活动度、疼痛、恢复工作时间及腕关节功能评分。结果对本组患者进行随访1～8.5年,平均3.6年;骨折愈合时间为7～12周,平均10.8周。腕关节平均评分85.2分;功能优28例,良21例,差0例。所有患者均恢复原来的工作或改为较轻的工作。结论经皮或切开复位螺钉固定、带血管蒂桡骨茎突骨瓣移植是治疗舟骨骨折的一种好方法;骨折类型不同,手术方法也需有所变化。Acutrak钉固定效果好于空心钉或可吸收钉。短期随访,未见有桡骨茎突切除的并发症。桡腕关节桡侧切口有利于显露骨折端及骨瓣制备,值得推荐。带血管蒂桡骨茎突骨瓣移植可缩短骨折愈合时间。     

Internal fixation of scaphoid non-union: a comparative study of three methods

In this study we compared the results of three methods of fixation for scaphoid non-union. The implants used were the AO 2 mm mini-fragment screw, the Herbert screw and the Kirschner (K) wires. Between 1990 and 1999, 132 patients underwent surgery for scaphoid fractures. We used the modified Filan and Herbert classification. Patients with acute fractures and patients requiring vascularised bone grafts were excluded. Twenty-six non-unions were fixed with an AO mini-fragment screw, 58 with a Herbert screw, and nine with K-wires. Radiological union was achieved in 85% of cases using the AO screw, 77% using the Herbert screw and 55% using the K-wire fixation. Statistically there was no significant difference between the AO and Herbert screw groups in terms of rate and speed of radiological union. The mechanical strength of the implant and the compression achieved did not seem to influence the union rate and speed. The type of bone graft (iliac crest or distal radius) did not significantly affect the union rates. Finally, K-wire fixation, either as a primary method or as a salvage procedure, produced inferior results and required prolonged immobilisation in plaster.     

Acutrak screw fixation versus cast immobilisation for undisplaced scaphoid waist fractures

Fifty-three patients with less than 14 day-old, undisplaced fractures of the waist of the scaphoid were randomized to two groups. Twenty-eight patients were treated by immobilisation in a below elbow plaster cast for 10 weeks while 25 were treated by percutaneous insertion of an Acutrak standard screw. There were no statistically significant differences between the two treatment groups with regard to either the rate of union or the time to union. Patients who underwent surgery had a significantly better range of motion at 16 weeks but there were no significant differences for grip strength. Acute percutaneous internal fixation of undisplaced scaphoid waist fractures using the Acutrak screw allows early mobilisation without adverse effects on fracture healing.     

Comparison of headless screws used in the treatment of proximal nonunion of scaphoid bone

Screws with different levels of compression force are available for scaphoid fixation and it is known that the Acutrak screw generates greater compression than the Herbert screw. We retrospectively compared two types of headless compression screw for their effectiveness in the repair of scaphoid nonunion. Twenty-nine cases of proximal scaphoid nonunion were surgically treated with non-vascularised bone graft: the Acutrak screw was used in 17 patients and the cannulated Herbert screw in 12 patients. Wrist range of motion, Mayo wrist score, grip strength and QuickDASH scores were indicators used for the functional evaluation. Radiographic findings were assessed for consolidation of nonunion and signs of arthrosis. The mean follow-up time was 49.2 months (range 12–96). Statistically, there was no significant difference between the Acutrak and Herbert screw types in terms of functional evaluation and time required for consolidation. Greater compression did not influence the functional outcome, consolidation rate or time to consolidation. The need for greater compression in the treatment of proximal scaphoid nonunions is thus questionable because it may increase the risk of proximal fragment communition.     

Interfragmentary compression forces of scaphoid screws in a sawbone cylinder model

Various screws have been developed to stabilise fractures of the scaphoid. Commonly used are the Herbert, the HBS, the 3-mm AO and the Acutrak screws. Not long ago a new screw, the Twin Fix, was introduced. This is cannulated and similar in shape and appearance to the classical Herbert screw. In our test series we compared the maximum achievable compression forces of the Twin Fix screw with that of three other screws (AO, HBS and Acutrak screws). To avoid the variations of density, stiffness and rigidity in natural bone, a polyurethane sawbone-based test setup was used. The test series included 10 screws of each type. The compression force was measured using a special strain gauge. The mean compression force was significantly higher for the Twin Fix screw (8+/-1N) and the Acutrak screw (7.6+/-0.4/0.6N) in relation to the AO screw (6.8+/-1.0/1.4N) and HBS screw (2+/-1N). We found the Twin Fix and Acutrak screws to be promising in the treatment of scaphoid fractures.     

Bold螺钉治疗新鲜腕舟骨骨折疗效分析

目的探讨使用Bold螺钉内固定治疗新鲜腕舟骨骨折的疗效。方法对本院2004年1月-2007年6月期间采用Bold螺钉内固定治疗的19例新鲜腕舟骨骨折病例进行回顾性分析。骨折根据Herbert分型分为B2型骨折16例,B4型骨折3例。结果19例患者均获得随访,随访时间为7～22个月,平均11个月。骨折均获骨性愈合。末次随访时用改良Mayo法对腕关节功能进行评估,优12例,良5例,可2例,优良率为89．5％。结论对于不稳定的新鲜腕舟骨骨折（Herbert分型B型）,采用Bold螺钉内固定治疗可减少骨折不愈合率,促进腕关节功能恢复,改善预后。     

Biomechanical comparison of fixation devices in experimental scaphoid osteotomies

This study determined the force, bending rigidity, and bending moment at failure of three types of internal fixation systems for the scaphoid bone. A pair of parallel, 0.045-inch Kirschner wires were compared on a paired, bilateral basis with either a Herbert screw or a 3.5 millimeter cannulated screw in repairing a transverse waist osteotomy in cadaver scaphoids. The mean values at failure of the Herbert screw and the cannulated screw versus the paired, parallel Kirschner wires for force (65 N and 77 N versus 23.7 N), rigidity (0.47 Nm2 and 0.54 Nm2 versus 0.16 Nm2) and bending (0.98 Nm and 1.15 Nm versus 0.36 Nm) were approximately three times greater. These differences were statistically significant when compared on a paired basis. This experiment demonstrates that the Herbert screw and cannulated screw are significantly stronger in resisting bending forces than paired, parallel Kirschner wires.     

小型双端螺纹加压钉的研制和临床应用

参照Herbert螺钉和AO松质骨螺钉的特点研制了小型双端螺纹加压钉及其器械。共治疗关节内骨折33例,其中肱骨小头骨折10例,桡骨头骨折8例,新鲜腕舟骨骨折6例,腕舟骨骨折骨不连4例和股骨头骨折5例。术后平均随访35个月,术后功能恢复均达到优良。该螺钉对这些关节内骨折能提供牢固的内固定,术后很少需石膏外固定,并且大多数病人在数周内恢复原工作。在处理这类骨折中,本治疗方法比常规方法具有明显的优越性。