骨水泥强化骨质疏松性椎体椎弓根螺钉的研究进展

目前椎弓根螺钉固定技术作为脊柱后路稳定的"金标准",已被广泛应用于临床.如果病人合并骨质疏松症,其内固定失败的风险将大大增加.骨水泥强化技术不仅能够显著提高骨质疏松性椎体术后骨质疏松椎体的稳定性,还能明显改善固定节段的周期性抗屈能力,为骨质疏松性椎体提供坚强、持久的内固定,从而有效重建脊柱的稳定性.但骨水泥强化技术也存在并发症,如骨水泥渗漏、加快邻近节段退变、增加骨折风险等.本文通过对骨水泥强化椎弓根螺钉固定的力学特性、骨水泥的选择、强化方式及近远期并发症等方面对骨水泥强化椎弓根螺钉固定技术进行综述.     

骨水泥强化椎弓钉用于骨质疏松腰椎手术二次置钉

[目的]比较骨水泥注入钉道后再次置入普通椎弓根螺钉(conventional pedicle screw with cement augmentation,CPS-CA)与更换侧孔空心椎弓螺钉再注入骨水泥进行钉道强化(fenestrated pedicle screws with cement augmentation...     

直入式注入PMMA骨水泥强化椎弓根钉内固定生物力学研究

【摘要】 目的 分析直入式骨水泥注入椎体强化方法在体外提高螺钉稳定性的效果。方法采用新鲜尸体脊柱标本共24个椎体,一侧椎弓根采用直入式注入PMMA骨水泥强化椎弓根钉固定作(试验组),另一侧椎弓根采用常规椎弓根螺钉固定(对照组),两侧进行最大轴向拔出力试验、最大旋出力矩试验、周期抗屈试验生物力学测试,比较两组测试结果。结果〓骨水泥强化组中螺钉的稳定性均显著强于单纯常规椎弓根螺钉组(P < 0.05)。结论〓应用PMMA行椎体强化椎弓根钉固定有利于增强对椎弓根钉的把持力,可有效防止椎弓根钉的松动及脱落,具有良好的临床效果。     

新型椎弓根钉骨水泥强化系统的生物力学与骨水泥剂量关系

目的建立骨质疏松模型,研究骨质疏松情况下新型经皮长U形空心椎弓根钉骨水泥强化系统(PMI-NPPS)的生物力学与骨水泥剂量之间的关系。方法取年龄在2.5~3.0岁绵羊腰椎,根据羊腰椎大小定做特定尺寸的羊PMI-NPPS。将40个椎体分成A、B组,B组脱钙4 h,分别进行骨密度测量,统计学分析确认骨质疏松模型建立。制备50个骨质疏松椎体随机分成5组,置入羊PMI-NPPS及骨水泥,按剂量分为0 ml组、0.5 ml组、1.0 ml组、1.5 ml组、2.0 ml组,进行生物力学测试,然后得出骨水泥剂量与Fmax(最大拔出力)的关系。结果 A组骨密度值为(0.875±0.003)g/cm~3、B组骨密度值为(0.631±0.003)g/cm~3,B组骨密度值低于A组,差异有统计学意义(P0.05)。脱钙后椎体骨密度较脱钙前降低27.9%。0 ml组、0.5 ml组、1.0 ml组、1.5 ml组、2.0 ml组的Fmax分别为(372.34±47.96)N、(613.85±30.37)N、(760.64±51.18)N、(896.59±47.97)N、(1 011.59±47.97)N。Pearson相关分析结果提示骨水泥剂量与Fmax呈直线相关,线性回归方程为y=312.5x+418.75(R~2=0.977),且1.5 ml为最理想的骨水泥剂量。结论当骨水泥剂量为0~2 ml时,随着骨水泥剂量的增加,羊PMI-NPPS的Fmax越高,且呈线性相关;当骨水泥剂量为1.5 ml时,羊PMI-NPPS的Fmax可达到正常骨密度时内固定的强度。     

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。     

骨水泥强化椎弓根螺钉在腰椎滑脱伴骨质疏松椎体中的临床应用

目的 探讨骨水泥强化椎弓根螺钉在腰椎滑脱伴骨质疏松患者的手术方法和疗效.方法 2008年7月至2010年11月年期间收治腰椎滑脱伴骨质疏松患者12例,平均68岁.骨质疏松按Jikei分级Ⅱ级4例,Ⅲ级8例.所有患者行经椎弓根螺钉内固定,术中采用骨水泥强化提高螺钉稳定性,植入椎弓根螺钉共26枚,观察椎弓根螺钉术中及术后的稳定性.结果 患者未发生手术并发症,腰腿痛症状改善明显,术后VAS评分较术前比较改善明显.12例患者均获得随访,随访时间8-16个月,平均14个月.12例均获得骨性融合,X线片显示内固定无松动、断裂或脱落,螺钉周围未见透亮线出现.结论 经椎弓根骨水泥强化椎弓根螺钉,固化椎体的同时增加了椎弓根螺钉界面把持力,能够满足腰椎滑脱伴骨质疏松患者脊椎后路固定手术对力学稳定的要求.     

骨水泥强化椎弓根钉内固定治疗腰椎滑脱症合并骨质疏松的疗效观察

目的探讨骨水泥强化椎弓根钉内固定治疗腰椎滑脱症合并骨质疏松的临床疗效。方法回顾性分析自2015-03—2017-11采用骨水泥强化椎弓根钉内固定治疗的38例腰椎滑脱症合并骨质疏松。比较术前、术后3个月、末次随访时疼痛VAS评分、ODI指数、融合节段椎间隙高度、椎体滑脱角。结果 38例均获得随访,随访时间平均16.5(13～24)个月。所有患者椎体滑脱复位良好,末次随访时35例椎间植骨融合。随访期间未出现内固定松动、移位,无断钉、断棒。术后3个月疼痛VAS评分、ODI指数、融合节段椎间隙高度、椎体滑脱角较术前明显改善,差异有统计学意义(P 0.05);而末次随访时以上指标与术后3个月比较差异无统计学意义(P0.05)。结论骨水泥强化椎弓根钉内固定治疗合并骨质疏松的腰椎滑脱症可有效重建脊柱稳定性,提高椎弓根钉抗拔出力,安全可靠,值得临床推广。     

磷酸钙骨水泥强化椎弓根螺钉对骨质疏松性椎体骨折的临床意义

目的 :评价磷酸钙骨水泥 (calciumphosphatecement ,CPC)强化和修复椎弓根螺钉的生物力学效果。方法 :6具新鲜老人骨质疏松的脊柱标本 ,从T11～L4 共 36个椎体 ,随机选取其中 32个 ,分为 4组 ,每组 8个。A组 :随机选择一侧椎弓根放置直径为 6 .5mm的椎弓根螺钉 ,另一侧以直径为 3.5mm的钻头导孔。向两侧椎弓根孔道注入配制好的磷酸钙骨水泥 (CPC) 3～ 5ml ,体温下 ( 37℃ )放置 2 4h后 ,再行前述拔出实验。B组 :应用PMMA进行修复和强化 ,作为对照 ,操作方法同A组。C组 :植入椎弓根螺钉 ,添加或不添加CPC ,进行周期抗屈实验。D组 :相同方法 ,应用PMMA作为对照。结果 :CPC骨水泥强化组和修复组拔出力明显高于对照组 ,差异有显著性意义 (P <0 .0 5)。结论 :在植入椎弓根螺钉时添加具有生物活性的磷酸钙 (CPC)骨水泥可显著提高其初始稳定性     

短节段骨水泥强化椎弓根钉内固定治疗单椎体骨质疏松性压缩骨折的临床初步研究

目的探讨短节段骨水泥强化椎弓根钉内固定治疗脊柱单椎体骨质疏松性压缩骨折的临床效果。方法应用短节段骨水泥强化椎弓根钉内固定治疗单椎体骨质疏松性压缩骨折22例。结果本组获随访12～24个月,术后疼痛20例完全缓解,1例部分缓解,1例轻微缓解,无原椎体再发塌陷,未出现神经再受累症状。结论短节段骨水泥强化椎弓根钉内固定治疗脊柱单椎体骨质疏松性压缩骨折,内固定可靠,是一种相对微创、有效的治疗方法。     

A demineralized calf vertebra model as an alternative to classic osteoporotic vertebra models for pedicle screw pullout studies

Screws, clamps and other spinal instrumentation materials are tested using healthy animal and healthy human vertebrae, but the application of similar tests to an osteoporotic vertebra is generally neglected because of high costs and limited availability of high quality and consistent osteoporotic vertebrae. The objective of this study is to develop an in-vitro method to decrease the mineral content of an animal vertebra utilizing decalcifying chemical agents that alters the bone mineral density and some biomechanical properties to such an extent that they biomechanically mimic the osteoporotic spine. This study was performed on 24 fresh calf lumbar vertebrae. Twelve out of these 24 vertebrae were demineralized and the others served as control. A hole was opened in the pedicles of each vertebrae and the bone mineral density was measured. Each vertebra was then placed into a beher-glass filled with hydrochloric acid decalcifier solution. The decalcifier solution was introduced through the holes in the pedicles with an infusion pump. The vertebrae were then subjected to DEXA to measure post process BMD. Pedicle screws were introduced into both pedicles of each vertebrae and pullout testing was performed at a rate of 5 mm/min. The difference of BMD measurements between pre- and post-demineralizing process were also statistically significant (p < 0.001). The difference of pullout loads between pre- and post-demineralizing process were also statistically significant (p < 0.001). The acid demineralizing process may be useful for producing a vertebra that has some biomechanical properties that are consistent with osteopenia or osteoporosis in humans.     

骨质疏松绵羊腰椎膨胀式椎弓根螺钉与骨水泥强化椎弓根螺钉固定稳定性的动态比较研究

【摘要】 目的：比较骨质疏松绵羊腰椎膨胀式椎弓根螺钉（expansive pedicle screw,EPS）与骨水泥强化椎弓根螺钉（polymethylmethacrylate-augmented pedicle screw,PMMA-PS）固定的动态稳定性。方法：8只健康成年雌性绵羊,体重55.7±5.6kg,年龄5.5±0.7岁。行双侧卵巢切除术（去势手术）后1个月开始连续肌肉注射甲基强的松龙（0.45mg/kg/d）10个月,在建模前、激素注射结束后1个月（建模后）测量绵羊腰椎的骨密度（bone mineral density,BMD）,BMD显著下降（>25%）时为骨质疏松动物模型成功建立。建模后将每只骨质疏松绵羊腰椎（L1~L6）随机分为3组,每组2个腰椎。普通椎弓根螺钉（conventional pedicle screw,CPS）组,直接拧入CPS;PMMA-PS组,向钉道内注入聚甲基丙烯酸甲酯（PMMA,1.0ml）后拧入CPS;EPS组,直接拧入EPS。螺钉置入术后6周和12周各处死4只绵羊,取出腰椎,剔除标本周围软组织,自各椎间盘处离断,游离成单个椎体。每个腰椎随机选择一侧的螺钉行轴向拔出实验,将椎体固定于MTS 858生物材料实验机上,沿椎弓根螺钉长轴方向以5mm/min的加载速度进行轴向拔出实验,测量螺钉的最大轴向拔出力（the maximum pullout strength,Fmax）和能量吸收值（energy absorbed value,EAV）。结果：建模前、后绵羊腰椎的BMD分别为1.14±0.10g/cm2和0.83±0.07g/cm2,建模后BMD显著下降（P<0.05）,平均为27.2%（25.4%~28.9%）,骨质疏松绵羊模型成功建立。置钉术后6周EPS组和PMMA-PS组的Fmax分别为1252.13±203.51N和1426.38±235.75N,EAV分别为2.48±0.45J和2.84±0.55J,均显著高于CPS组（827.88±139.22N和1.66±0.30J）（P<0.05）;置钉术后12周EPS组和PMMA-PS组的Fmax分别为1518.88±256.81N和1472.75±248.65N,EAV分别为3.09±0.59J和2.95±0.60J,均显著高于CPS组（906.63±152.50N和1.80±0.35J）（P<0.05）;置钉术后6周、12周EPS组的Fmax和EAV与PMMA-PS组比较差异均无统计学意义(P>0.05)。置钉术后12周CPS组和PMMA-PS组的Fmax和EAV与同组置钉术后6周比较无显著性变化（P>0.05）,置钉术后12周EPS组的Fmax和EAV较同组置钉术后6周均有显著性提高（P<0.05）。结论：与CPS相比,EPS可显著提高螺钉在骨质疏松绵羊腰椎中的稳定性,并达到了与临床常用的PMMA-PS近似的固定效果。     

Efficacy of novel-concept pedicle screw fixation augmented with calcium phosphate cement in the osteoporotic spine

Pedicle screw instrumentation has become increasingly popular for rigid internal stabilization of the thoracolumbar spine. However, when pedicle screws are used in elderly osteoporotic patients, the screw–bone interface is stripped easily. Therefore, the risk of screw loosening and backing-out after surgery has increased. The purpose of this study was to evaluate the efficacy of the novel-concept pedicle screw fixation augmented with calcium phosphate cement (CPC) in the osteoporotic spine. The novel-concept screw has the same shape as the ordinary screw, but it is hollow and fabricated with 20 small holes (1.3mm in diameter) leading to the hollow part on the bottom of the thread. Fifteen embalmed cadaveric lumbar vertebrae were instrumented with two types of pedicle screw (the ordinary screw and the novel-concept screw) in each pedicle. Only the novel-concept screws were augmented with CPC after insertion. Seven days later, axial pull-out testing was performed at a crosshead speed of 10mm/min. The mean maximal pull-out strength of the ordinary screws was 258N, and that of the novel concept screws was 637N. These results suggest that the novel-concept screw augmented with CPC can be useful for pedicle screw fixation of the osteoporotic spine.     

多节段椎体增强后椎弓根钉内固定系统在骨质疏松性椎体骨折治疗中的应用

目的探讨多节段椎体增强后应用椎弓根钉内固定系统治疗骨质疏松性椎体骨折的疗效。方法自2004年起应用骨水泥强化椎体后椎弓根钉内固定系统治疗骨质疏松性椎体骨折12例,观察后凸Cobb角矫正度、内固定稳定情况及临床症状改善程度。结果12例患者获随访6~24个月,平均13个月,椎弓根钉内固定系统无松动、脱落、折断。后凸畸形Cobb角平均矫正24.2°,疼痛VAS评分由术前平均8.7分降至术后平均2.5分,ODI评分(%)由术前平均71.5改善至术后平均32.5。结论应用椎体增强后椎弓根钉内固定系统治疗骨质疏松性椎体骨折可获得满意的临床疗效。     

Enhancement of pedicle screw stability using calcium phosphate cement in osteoporotic vertebrae: in vivo biomechanical study

 We conducted an experimental study using female beagles with and without ovariectomy-induced osteoporosis to determine the effect of calcium phosphate cement (CPC) on the mechanical stability of inserted pedicle screws. A drill hole was created from the base of the transverse process to the vertebral body; CPC was injected into the hole, and then a screw was inserted into the same hole. In the presence of osteoporosis evidenced by dual X-ray absorptiometry, the stability of the inserted screw augmented by CPC against pull-out and cephalocaudal forces were significantly greater by 28% and 54% at 1 week after operation, 48% and 71% at 2 weeks, and 56% and 68% at 4 weeks compared with those without CPC. The pull-out strength increased progressively with time after surgery, probably reflecting new-bone growth from the surrounding cancellous bone, which was in direct contact with the CPC, as shown in the histologic study. At each time point the cephalocaudal rigidity was similar and the pull-out strength greater than that for the screws inserted without CPC in nonporotic dogs. These findings suggest that CPC augments the stability of the inserted pedicle screws and increases the stiffness of fixed osteoporotic motion segments using instrumentation. Received: September 9, 2002 / Accepted: January 6, 2003 RID="*" ID="*" Offprint requests to: Y. Taniwaki     

骨水泥强化椎弓根螺钉固定的研究进展

椎弓根螺钉固定技术是脊柱后路固定的标准技术,但在骨质疏松情况下固定易松动失效,常需要行骨水泥强化以提高固定效果.本文简要介绍了疏松性椎骨骨-钉界面生物力学、骨水泥强化固定的方法和材料.并指出强化固定的指征和可吸收材料在骨质疏松性骨质强化巾的替代过程及其强度可能是值得期待的研究方向.     

医用骨水泥在骨质疏松患者行椎弓根钉固定中的作用

目的：探讨应用骨水泥在骨质疏松患者行椎弓根钉同定术的临床效果和安全性。方法：对20例骨质疏松患者经骨水泥灌注后行椎弓根钉固定术，比较患者术后1周和复查时的X线片，观察内置物有无松动，骨水泥固定螺钉周围有无透亮线出现。并对复查患者行固定节段的CT扫描，观察螺钉周围有无透亮线出现。结果：18例(90％)患者获随访，平均随访时间18个月，X线片中均未发现内置物松动或脱出，固定节段植骨愈合良好．在骨水泥固定螺钉周围未发现有透亮线出现；CT扫描在螺钉周围也未发现透亮线出现。结论：对于骨质疏松患者．应用骨水泥对椎弓根钉固定进行加固可防止内置物松动脱出，有较好稳定脊柱的临床效果。但应注意手术技巧，确保没有骨水泥渗漏。     

经皮椎体成形术与椎弓根螺钉固定治疗骨质疏松性胸腰椎骨折的生物力学研究

目的比较经皮椎体成形术(PVP)和椎弓根螺钉内固定(PSF)治疗骨质疏松性胸腰椎骨折的生物力学强度,为临床应用和离床活动指导提供实验依据。方法18具冻存的新鲜尸体,应用双能X线骨密度仪(DEXA)测定脊柱的骨密度(BND),取胸腰段脊椎(T_(12)～L_2 12具,L_1 6具)随机分成三组：PVP组、PSF组(T_(12)L_2)和正常对照组(L_1),每组6具。PVP组和PFS组实验椎体均制成骨折模型,PVP组给予经双侧椎弓根注入低粘度的含显影剂骨水泥各2．5mL。PSF组于T_(12)、L_2椎弓根置入钉棒系统固定,测试并比较两组和对照组静态最大抗压强度及刚度。结果PVP组骨水泥分布面积皆大于50%,其平均最大抗压强度与刚度分别为(2645±478)N,(117±81)N/mm；PSF组平均最大抗压强度与刚度分别为(1862±620)N,(125±33)N/mm。两组比较平均最大抗压强度差异有显著性意义(P＜0．05),最大刚度差异无显著性意义(P＞0．05)。结论骨折椎体内注入骨水泥PMMA,其抗压强度优于椎弓根钉方法,对于轻度骨质疏松者尤为适用。PVP术后患者可早期(3～5d)下床活动,而PSF术后患者离床活动时间可适当延后。     

寰椎椎弓根螺钉联合经寰枢关节螺钉内固定稳定性的生物力学研究

目的:评估寰椎椎弓根螺钉联合经寰枢关节螺钉固定技术的力学稳定性.方法:选取成人颈椎新鲜标本6具,解剖剔除肌肉制备上颈椎完整模型(完整组),用生物力学测试及计算机视觉分析软件测量在1.5Nm力矩下前屈后伸、左右侧弯和左右旋转时C 1-C2的活动度(ROM);破坏寰椎前弓和侧块制备不稳模型(失稳组),再次测量相同力矩下各运...     

Biomechanical evaluation of an expansive pedicle screw in calf vertebrae

incetheintroductionofthetranspedicularscrewsystembyBoucher ,1theapplicationofthissysteminthetreatmentofdegenerativedisordersandunstablefractures ,tumorsofthespinehasbecomeverypopularinthelasttwodecades.2 Looseningandfailureofthescrewsareamongthemostcommoncomplicationsreported ,especiallyforosteoporosis .3Thesefailuresoftenleadtonon union ,sagittalcollapseoftheconstructandpainfulkyphosis .Revisionisoftennecessary .Increasingthediameterand/orlengthofthepediclescrewseemstobethebestsolution .Howe…