骶骨不同水平切除对骨盆稳定性影响的生物力学研究

目的 研究正常骶骨的力学特性和选择性骶骨切除后对骨盆力学结构产生的生物力学效应,探讨骶骨部分切除后重建的必要性.方法 采用6具成人防腐骨盆标本,于试验器具内固定双侧坐骨结节模拟坐姿,通过WE-5电子万能试验机分级加载0、200、400、600、800、1000 N,在骨盆上沿着主应力迹线方向布置电阻应变片,分别测量并记录骨盆完整时、经S3、S2、S1神经孔上下缘横行切除骶骨时、切除一侧骶髂关节时骨盆的主要应力传导路径和应力分布、应力应变关系、位移趋势及刚度变化,测量并记录经S1神经孔上缘切除后残余骶骨结构的极限载荷.结果 骶骨主要应力分布于S1上方,经S1神经孔上缘平面切除应力传导方向发生改变,局部应力集中发生突变,其轴向刚度和弯曲刚度严重削弱,旋转和轴向稳定性差,骶骨承重能力下降明显(P＜0.05).其极限载荷接近或低于站立前屈下生理载荷,有骨折的危险.结论 S1神经孔以上骶骨是应力传导的最重要结构,切除达S1神经孔上缘平面以上结构损害了骶骨正常生理承载能力,骶骨次全切除或全切除术后应行内固定重建以恢复生理性应力传导.     

骶骨部分切除对骶髂关节生物力学的影响

目的:评价骶骨部分切除对骶髂关节生物力学的影响;明确骶骨切除范围与稳定重建的关系.方法:7具成人尸体L5-骨盆标本;分别在完整状态、S2以下切除(A组)、1/2 S2以下切除(B组)、S1以下切除(C组)、1/2 S1以下切除(D组)、右侧骶髂关节切除(E组)等情况下通过858型MTS材料实验机给标本施加800N轴向压缩和7Nm轴向扭转载荷;记录完整状态及残留骶髂关节刚度;比较各组间的差异.结果:轴向压缩时;A组～E组残留骶髂关节刚度分别是完整状态组的98.7%、97.1%、94.4%、82.9%和55.2%;完整状态组、A组、B组和C组间的压缩刚度无显著性差异;D组和E组的轴向压缩刚度显著低于完整状态组.轴向旋转时;A组～E组残留骶髂关节刚度分别为完整状态刚度的90.7%、88.5%、81.9%、71.9%和44.5%;完整状态组、A组和B组间的旋转刚度值无显著性差异;C组、D组和E组的轴向旋转刚度显著低于完整状态组和A组.结论:骶骨切除范围与骶髂关节稳定性相关.骶骨向上切除至S1将导致骶髂关节旋转失稳.切除至1/2 S1将进一步引起残留骶髂关节的轴向压缩失稳.骶骨切除超过上述范围时应考虑局部稳定性重建.     

选择性骶骨切除后骨盆力学特性变化的三维有限元分析

目的 研究正常骨盆和选择性切除骶骨后骨盆力学特性变化.方法 应用CT影像资料建立正常骨盆和选择性切除骶骨后骨盆的三维有限元模型,计算分析生理载荷下骶骨及整个骨盆的应力分布和应力传导变化.结果 骶骨应力主要分布在S1.经S3孔上缘、经S2孔下缘、经S2孔上缘切除时骨盆应力分布和传导变化很小.经S1孔下缘切除时骶髂关节局部应力值明显增加为2.1倍,经S1孔上缘时应力值急剧增加达4.3倍.结论 骶骨的主要应力传导结构位于S1,骶骨切除S1孔平面以下对骶骨应力传导影响较小,切除达S1孔平面以上将严重损害骨盆的稳定性,承重能力的降低可能导致骨折的危险.     

骶髂关节解剖型棒-板内固定系统的生物力学评价

目的：探讨采用新型骶髂关节解剖型棒-板内固定系统（SABP）治疗骨盆骶髂关节骨折脱位的生物力学性能。方法：采集新鲜的冷冻尸体骨盆标本20具,造成骨盆骨折模型,采用实验应力分析方法,对SABP内固定和骶骨螺钉结合Galveston技术内固定、骶骨棒固定、重建钢板固定、骶髂关节螺钉等5种固定作对照比较,分别测定它们的刚度和强度,用以评价骨盆的稳定性。结果：采用新型骶髂关节解剖型棒-板内固定系统治疗骨盆骶髂关节骨折脱位,较骶骨螺钉结合Galveston技术内固定、骶髂关节螺钉、重建钢板固定、骶骨棒固定其骨盆的刚度分别高10%、11%、16%、21%,强度分别高12%、14%、21%、31%;应变分别小13%、14%、22%、25%,位移分别小10%、12%、16%、20%,差异有统计学意义（P〈0.05）,并且超过正常人骨盆标本,但差异无统计学意义（P〉0.05）。结论：采用新型SABP内固定装置治疗骨盆骨折,其强度、刚度最佳,优于其他内固定方法,是一种理想的新型内固定器械。     

后路短螺丝钉固定术治疗骶髂关节骨折脱位实验研究与临床

目的:探讨后路短螺丝钉固定治疗骶髂关节骨折脱位的安全性和疗效。方法:骶骨应用解剖,骶髂关节脱位模型生物力学实验,11例病人手术方法及疗效分析。结果:应用解剖,(1)骶骨耳状面下缘在S_(2、3)后孔连线中下1/3以下者占86.6％;(2)S_(2、3)侧柱呈直角梯形。S_2侧柱横截面前后径(28.3±1.7)mm,S_3侧柱横截面前后径中部为(21.4±1.5)mm,中下1/3处为(8.4±1.1)mm;(3)骶后中间嵴到耳状面中轴垂直距离:S_2水平处(26.7±2.6)mm,S_3水平处(27.2±2.8)mm。骶后孔连线:S_(1、2)间(17.4±1.6)mm,S_(2、3)间(17.6±2.1)mm。生物力学:(1)2枚短螺丝钉固定可以控制骶髂关节的移位,同时前部固定后明显增加骨盆的强度和刚度,并可以对抗剪切力。临床部分:治疗11例病人平均随访5.4年,优7例,良4例。结论:后路短螺丝钉经过骶骨侧柱中上部,不超过骶孔连线固定骶髂关节,不但能获得牢固的固定,同时能有效的避免神经损伤,骶髂关节植骨融合其远期疗效好。     

骨盆韧带损伤对骶髂关节稳定性影响的生物力学研究

目的 探讨骨盆韧带损伤对骶髂关节稳定性的影响,为骨盆骨折的临床治疗提供理论依据. 方法取骨盆标本10具,完整保留关节及韧带结构,左侧组逐级离断耻骨联合、骶棘韧带、骶结节韧带、骶髂前韧带及骶髂前关节囊、骶髂骨间韧带,右侧组逐级离断耻骨联合、骶髂后长、后短韧带、髂腰韧带、骶髂骨间韧带,模拟人体单足站立位,力学机上给予轴向加载,测量并记录骶骨相对于髂骨的垂直位移及矢状面骶骨旋转角度(角移位). 结果左侧力学试验中,仅切断耻骨联合周围韧带、骶结节韧带,骶骨垂直位移、骶骨角位移,差异无统计学意义(P＞0.05).逐步切断骶髂前韧带、骶髂骨间韧带,骶骨的垂直位移数值由完整骨盆测量的(4.144±0.538)mm增至(5.853±0.368)mm;骶骨的旋转角度由骨盆完整时的0.226°±0.061°增至0.616°±0.086°,差异有统计学意义(P＜0.05).右侧力学试验中,逐次切断骶髂关节后部韧带,骶骨的垂直位移数值由完整骨盆测量的(3.610±0.696)mm增至(6.825±0.565)mm;骶骨的旋转角度由骨盆完整时的0.271°±0.094°增至0.746°±0.192°,差异有统计学意义(P＜0.05).结论 耻骨联合及其周围韧带的损伤对骶髂关节的稳定性无显著性影响;骶结节韧带、骶棘韧带对限制骶骨的角位移有很大作用;骨间韧带对骶髂关节稳定性的作用较大;骶髂后韧带与骨间韧带共同组成了骶髂关节后部韧带复合体,是骶髂关节周围韧带中的重要部分.     

骶骨骨折内固定手术治疗进展

正骶骨由5块骶椎融合而成,骶管内有马尾神经,骶前后孔有骶神经,周围还毗邻许多神经、血管及盆腔脏器。在重力及应力传导中,L5S1椎间盘约占腰骶生物力学的80%,同时作为骨盆后环的骶髂关节复合体,其稳定功能占整个骨盆的60%。骶骨骨折较为复杂,有可作为骨盆环损伤的一部分Tile分型,对腰骶稳定性影响的Isler分型,按骨折线分类的Gibbons分型,按骨折位置分类的Denis分型,每一种骨折类型还要细分为     

骶髂关节脱位直视复位空心螺钉固定的基础研究及临床应用

目的研究总结直视复位、经皮空心螺钉固定骶髂关节脱位的解剖学基础、生物力学稳定性以及初步的临床疗效。方法采用12具(24侧)福尔马林固定的尸体标本,测量骶骨翼上缘L_4、L_5神经根前支和闭孔神经至骶髂关节的距离。采用6具新鲜尸体骨盆标本建立骶髂关节脱位模型,比较本固定法与传统后路经皮骶髂关节螺钉和前路钢板固定的稳定性。同期采用本固定法手术治疗17例Tile C型骨折患者,随访疗效。结果①L_4、L_5神经根及闭孔神经分别距离骶髂关节(20．24±1．12)mm、(23．80±1．43)mm、(16．26±2．07)mm；②本固定方式与后路经皮骶髂关节螺钉的稳定性无显著性差异,但优于前路钢板固定；③临床治疗17例患者,平均随访2．2年,根据Matta功能评定标准,功能恢复均为优良。结论该固定系统具有良好的生物力学稳定性,同时可避免神经损伤、临床效果好、操作简便,便于基层医院开展。     

不同方法治疗不稳定骨盆骨折中前环损伤的有限元分析

目的:比较5种不同固定方法治疗不稳定骨盆骨折中前环损伤的生物力学稳定性,为临床治疗提供参考。方法:使用三维有限元方法,建立一侧骶髂关节脱位合并耻骨支骨折的不稳定骨盆骨折模型(Tile C型),模拟前方采用5种不同的固定方法,后方统一采用骶髂螺钉进行固定,并在模拟站立状态下比较分析不同组合固定方法治疗后的骨盆环的von Mises应力及应变分布情况。结果:竖直方向500 N载荷加载后,前方骨折处最大应力3.56 MPa(前方外固定架组),骶髂关节和骨折处总位移和Y轴上垂直位移在应力下均未超过1.5 mm。其中前方经皮入路组和前方外固定架组在内固定、骨折前方、骶髂关节处的最大应力明显大于改良Stoppa入路组、传统的髂腹股沟入路组、空心螺钉组,且在骶髂关节和骨折处的总位移和Y轴上垂直位移也大于其他3组。结论:不稳定性骨盆骨折中的前环损伤在5种组合方法植入物的固定后均能得到明显的改善,但采用改良Stoppa入路、髂腹股沟入路、前方空心钉固定方法治疗前环损伤在生物力学总体性能要优于前方经皮入路和前方外固定架治疗的方法。     

改良张力带钢板重建骨盆后环的生物力学研究

[目的]通过生物力学研究验证一种新的改良张力带钢板重建不稳定性骨盆后环损伤的效果,并与其他两种方法比较。[方法] 8具成人骨盆标本,制成不稳定性骨盆环损伤(AO分类C1.2)模型,随机依次应用三种不同内固定来重建骨盆后环:传统张力带钢板;改良张力带钢板;双骶髂螺钉。分别依次予以0～600 N垂直和0～8 N·m扭转加载,测量整体骨盆环垂直位移和扭转角度并计算轴向和扭转刚度;测量损伤侧骶髂关节在垂直、左右和前后方向上的位移以及在矢状面上的旋转角度。[结果]在垂直和扭转载荷下,改良张力带钢板固定后的整体骨盆环垂直位移和扭转角度均明显小于传统张力带钢板(P0.05),虽大于双骶髂螺钉,但差异无统计学意义(P0.05);改良张力带钢板固定后的整体骨盆环轴向刚度和扭转刚度均明显大于传统张力带钢板(P0.05),虽小于双骶髂螺钉,但差异无统计学意义(P0.05)。垂直载荷下,改良张力带钢板伤侧骶髂关节在垂直、左右、前后方向上位移以及在矢状面上的旋转位移明显小于传统张力带钢板(P0.05)。[结论]与传统张力带钢板相比,改良张力带钢板重建骨盆后环提供了更好的生物力学稳定性。     

Biomechanical comparison of posterior pelvic ring fixation

OBJECTIVE: To determine relative stiffness of various methods of posterior pelvic ring internal fixation. DESIGN: Simulated single leg stance loading of OTA 61-Cl.2, a2 fracture model (unilateral sacroiliac joint disruption and pubic symphysis diastasis). SETTING: Orthopaedic biomechanic laboratory. OUTCOME VARIABLES: Pubic symphysis gapping, sacroiliac joint gapping, hemipelvis coronal plane rotation. METHODS: Nine different posterior pelvic ring fixation methods were tested on each of six hard plastic pelvic models. Pubic symphysis was plated. The pelvic ring was loaded to 1000N. RESULTS: All data were normalized to values obtained with posterior fixation with a single iliosacral screw. The types of fixation could be grouped into three categories based on relative stiffness of fixation: For sacroiliac joint gapping, group 1-fixation stiffness 0.8 and above (least stiff) includes a single iliosacral screw (conditions A and J), an isolated tension band plate (condition F), and two sacral bars (condition H); group 2-fixation stiffness 0.6 to 0.8 (intermediate stiffness) includes a tension band plate and an iliosacral screw (condition E), one or two sacral bars in combination with an iliosacral screw (conditions G and I); group 3-fixation stiffness 0.6 and below (greatest stiffness) includes two anterior sacroiliac plates (condition D), two iliosacral screws (condition B), and two anterior sacroiliac plates and an iliosacral screw (condition C). For sacroiliac joint rotation, group 1-fixation stiffness 0.8 and above includes a single iliosacral screw (conditions A and J), two anterior sacroiliac plates (condition D), a tension band plate in isolation or in combination with an iliosacral screw (conditions E and F), and two sacral bars (condition H); group 2-fixation stiffness 0.6 to 0.8 (intermediate level of instability) includes either one or two sacral bars in combination with an iliosacral screw (conditions G and I); group 3-fixation stiffness 0.6 and below (stiffest fixation) consists of two iliosacral screws (condition B) and two anterior sacroiliac plates and an iliosacral screw (condition C). DISCUSSION: Under conditions of maximal instability with similar material properties between specimens, differences in stiffness of posterior pelvic ring fixation can be demonstrated. The choice of which method to use is multifactorial.     

The role of standard roentgenograms in the evaluation of instability of pelvic ring disruption

Anteroposterior pelvic roentgenograms of 154 patients with pelvic ring disruptions were evaluated to assess their value in the determination of pelvic instability. Three different categories of stability were roentgenographically recognizable: (1) stable, characterized by impacted vertical fracture of the sacrum, nondisplaced fracture of the posterior sacroiliac complex, and/or subtle fractures of the upper sacrum evidenced by asymmetry of the sacral arcuate lines; (2) unstable, characterized by hemipelvic cephalad displacement exceeding 0.5 cm, sacroiliac joint diastasis exceeding 1 cm and/or sacral or iliac diastatic fracture exceeding 0.5 cm; and (3) indeterminate (that is, suspicious but not diagnostic of pelvic instability), characterized by cephalad hemipelvic displacement of less than 0.5 cm, sacroiliac joint diastasis less than 1 cm, and/or diastatic fracture of the sacrum or ilium of less than 0.5 cm. Correlation of the standard roentgenographic, computed tomographic, and clinical orthopedic examinations revealed that pelvic stability was accurately evaluated on the standard pelvic roentgenograms in 88% of cases. Disruptions were stable in 70%, unstable in 18%, and suspect in 12% of patients, for whom adjunct roentgenographic and clinical examinations were required. Determination of pelvic stability in the manner described allows immediate identification of patients with a stable or unstable pelvic injury, as well as identification of those with indeterminate stability requiring further clinical or roentgenologic evaluation. Immediate recognition of pelvic instability on standard pelvic roentgenograms obviates the need for additional diagnostic studies that unnecessarily delay the institution of emergency therapeutic measures designed to control associated hemorrhage.     

骶骨肿瘤的分区切除与重建方式的选择

目的：探讨对骶骨肿瘤按其发生部位进行分区切除，选择相应重建方式的方法及疗效。方法：1988年2月-2005年1月手术治疗43例骶骨肿瘤患者，按肿瘤侵及部位（即上段骶骨、骶髂关节及骶髂关节水平向外的髂骨是否被破坏）对骶骨肿瘤进行分区切除并重建，相应的手术及重建方式包括单纯切除、钢针加塑形骨水泥（CPC）重建骶骨、钢板螺钉固定或骶骨螺钉固定重建骶髂关节、不同长度的Luque棒或髂骨棒加钢丝缠扎或TSRH或Isola或CGWS腰椎骨盆内固定。并给予相应的放疗与化疗。结果：术后出现脑脊液漏2例，切口感染及延期愈合3例，切口皮肤边缘坏死1例，下肢深静脉血栓形成1例，经积极处理后均治愈。随访1-17年，平均75个月，43例患者中39例（90．7％）术后疼痛得到缓解，视觉模拟疼痛评分由术前平均8．5分降低到术后3.4分（P〈0．01）。14例有神经功能损害的患者中，11例术后症状改善，3例无改善。20例行自体和或异体植骨的患者术后1年16例获得骨性融合。3例脊索瘤、3例恶性纤维组织细胞瘤和4例骨巨细胞瘤患者于术后1年因复发而进行1次或多次手术，其中有5例和1例骨髓瘤、1例转移癌患者于术后17-50个月因肺部和全身转移死亡。发生断棒2例，均再次手术更换断棒。结论：按肿瘤部位进行分区切除，选择相应的重建方式，达到尽可能广泛切除肿瘤组织和维持脊柱及骨盆稳定性的目的．是取得良好疗效的重要保证。     

S1椎弓根螺钉结合髂骨板间螺钉治疗骶髂关节骨折脱位

目的 探索S1椎弓根螺钉结合髂骨板问螺钉治疗骶髂关节骨折脱位的临床疗效，评价两者结合对骶髂关节骨折脱位的治疗价值。方法 对11例骶髂关节骨折脱位患者用脊柱内固定系统(TSRH)之S1椎弓根螺钉结合髂骨板间螺钉进行固定，该组患者涉及骶髂关节的垂直移位及旋转的骨盆环变形，归于Tile分型的B类或C类骨盆损伤。11例患者均伴有前环损伤，其中9例予以加压钢板(smith nephew)内固定，余2例患者单纯采用后路手术内固定。结果 7例患者垂直移位完全复位，9例旋转畸形纠正，未发现感染及神经损伤等并发症。结论 S1椎弓根螺钉结合髂骨板问螺钉固定技术治疗骶髂关节骨折脱位，可获得即刻稳定性并良好地维持了复位的效果．这一混合技术对于涉及垂直及旋转损伤的骨盆环损伤有稳定的作用。     

Surgical technique of percutaneous iliosacral screw fixation in S3 level in unstable pelvic fracture with closed degloving injury and morrell lavallee lesion: Two case reports

IntroductionPercutaneous screw fixation is considered the best option in unstable pelvic fracture with severe soft tissue injury. However, fixation technique at the level of S3 has not been well established. This paper showed the feasible surgical technique of S3 screw insertion in unstable pelvic fracture with severe soft tissue injury.MethodsWe reported 2 cases of unstable pelvic injury of an 11 years old boy with Marvin-Tile (MT) C1 pelvic fracture with sacroiliac (SI) joint disruption, skin avulsion and Morel-Lavallée lesion. Second case was 30 years old male with open pelvic fracture MTB2 and vertical sacral fracture Denis zone I with Morel-Lavallée lesion, intraperitoneal bladder rupture, infected laparotomy wound dehiscence. We performed percutaneous screws insertion on both pubic rami and IS screw on S1 and S3 to both cases. Functional outcome was evaluated using Majeed and Hannover pelvic score.ResultsAll patients survived and had good reduction with no residual displacement on SI joint. The former case at 21-month follow up presented with excellent outcome (100/100) by Majeed score and very good outcome (4/4) by Hannover score; while the latter case, at 18-month, present with good outcome (85/100) Majeed score and fair outcome (2/4) Hannover score.ConclusionsPercutaneous screw fixation at the level of S3 is feasible and can be inserted in S3 level by sacroiliac type and sacral type with minimal soft tissue intervention and good functional outcome.     

Vertically unstable pelvic fractures fixed with percutaneous iliosacral screws: does posterior injury pattern predict fixation failure?

OBJECTIVE: To measure the failure rate of percutaneous iliosacral screw fixation of vertically unstable pelvic fractures and particularly to test the hypothesis that fixations in which the posterior injury is a vertical fracture of the sacrum are more likely to fail than fixations with dislocations or fracture-dislocations of the sacroiliac joint. DESIGN: Retrospective review. SETTING: Level 1 trauma center. METHODS: All patients with pelvic fractures admitted between January 1, 1993, and December 31, 1998, were identified from the trauma registry. Hospital records were used to identify patients treated with iliosacral screws. Radiologic studies were examined to identify patients who had unequivocally vertically unstable pelvic fractures. Immediate postoperative and follow-up anteroposterior, inlet, and outlet radiographs from a minimum of 12 months postinjury were examined. Position, length, and numbers of iliosacral screws and any evidence of screw failure (eg, bending or breakage) were recorded. Residual postoperative displacement and late displacement of the posterior pelvis were measured. The main outcome measure was failure, defined as at least 1cm of combined vertical displacement of the posterior pelvis compared with immediate postoperative position. The main analysis was for association between fracture pattern and failure. Patient demographic data, iliosacral screw position, and anterior pelvic fixation method also were studied. RESULTS: The study group comprised 62 patients with unequivocally vertically unstable pelvic fractures in whom the posterior injury was treated with closed reduction and percutaneous iliosacral screw fixation. Of patients, 32 had dislocations or fracture-dislocations of the sacroiliac joint, and 30 had vertical fractures of the sacrum. Fixation failed in four patients, all with vertical sacral fractures and all within the first 3 weeks after surgery. These four patients required revision fixation. In two further cases with vertical sacral fractures, there was evidence that the fracture had only barely been held by the fixation, but these fractures healed, and follow-up radiographs did not meet the displacement criteria for failure. A vertical sacral fracture pattern was associated significantly with failure (Fisher exact test, P = 0.04); the excess risk of failure compared with sacroiliac joint injury was 13% (95% confidence interval 1% to 25%). There was no significant association between failure and anterior fixation method, iliosacral screw arrangement or length, or any demographic or injury variable. CONCLUSIONS: Percutaneous iliosacral screw fixation is a useful technique in the management of vertically unstable pelvic fractures, but a vertical sacral fracture should make the surgeon more wary of fixation failure and loss of reduction.     

骨盆骨折CT扫描的临床价值

目的 探讨骨盆骨折ＣＴ扫描的临床价值。方法 分析１４例骨盆骨折ＣＴ扫描资料。结果 发现骶髂关节部分分离４例,完全分离３例,骶髂关节内碎骨２例,骶髂关节髂骨唇骨折２例,骶骨唇骨折３例,北骶孔骨折１例,髋臼内壁方形区骨折１例,髋臼后壁骨折并关节内碎骨１例。结论 骨盆骨折ＣＴ扫描可揭示Ｘ线平片不能确定的损伤,为临床精确诊断和正确处理提供重要依据。     

S1 pediculoiliac screw fixation in instabilities of the sacroiliac complex: biomechanical study and report of two cases

OBJECTIVE: A new technique for posterior sacroiliac fixation is described and compared with conventional techniques. PATIENTS/MATERIAL AND METHODS: A patient with sacral alar fracture (zone 1) and another one with sacroiliac joint instability due to tuberculous infection underwent fixation using screws placed in the S1 pedicle and the iliac bone. Vertical stability of the new technique also was investigated using polyurethane pelvic bone analogs and compared with anterior double plating (group P) and iliosacral screw fixation (group ISS) techniques. RESULTS: Healing was obtained and reduction was maintained in both patients on the final follow-up examination at 2 years postoperatively. Vertical loading tests revealed that failure loads within the first 10 mm of displacement of the new pediculoiliac screw fixation technique (group PIS) was higher than plating (P = 0.03) and lower than ISS techniques (P = 0.002). Ultimate failure load of the PIS technique was slightly higher than plating (P = 0.277) and lower than ISS techniques (P = 0.003). With the addition of an iliosacral screw to the pediculoiliac screw construction (PIS+ISS), the PIS technique became more stable in early (P = 0.110) and ultimate failure loads (P = 0.003). CONCLUSIONS: Pediculoiliac screw fixation for sacroiliac joint disruptions and zone I sacrum fractures using iliac and S1 pedicle screws is a new and effective alternative for obtaining and maintaining anatomic reduction.     

髂骨翼与髋臼上置钉技术在Tile B1型骨盆骨折外固定的有限元研究

目的 对髂骨翼(IW)与髋臼上方(SA)2种置钉技术在Tile-B1型骨盆骨折固定的生物力学机理进行有限元分析,为临床治疗提供参考.方法 构建包含韧带结构的骨盆三维有限元模型,模仿Tile B1型骨盆骨折工况.在Abaqus有限元软件中进行模拟加载,比较SA外固定支架、IW外固定支架及耻骨联合钢板固定等工况的生物力学特点.结果 位移分析提示耻骨联合部位坚强的固定有利于控制水平方向的位移.Mises应力云图显示IW外固定支架主要通过直接将健侧应力传导至患侧髂骨翼;而SA外固定支架一方面将健侧应力直接传导至患侧髋臼上方,另一方面也增加了骶髂关节的应力传导.由于髋臼上骨质厚实,置入较粗固定钉的安全性较好.结论 SA外固定支架技术可有效恢复骨盆前方稳定性,且有利于后方骶髂关节稳定性的重建,生物力学性能总体优于传统IW外固定支架技术,是Tile B1型骨盆骨折的良好固定方式.

Abstract：

Objective To compare iliac wing (IW) and supra-acetabular (SA) external fixations for treatment of Tile Bl pelvic fracture through a finite element biomechanical analysis. Methods A three-dimensional finite element model of the pelvis including the ligament structure was constructed. Conditions of Tile B1 pelvic fracture were simulated in the model. In the Abaqus finite element software, simulated loads were applied to compare biomechanical parameters of SA, IW, and pubic symphysis (PS) fixations.Results Displacement analysis indicated that strong PS fixation benefited control of the horizontal displacement. Mises stress contour showed that the IW bracket directly transmitted the stress from the unaffected side to the affected side to restore the stability of the sacroiliac joint. The SA bracket not only directly transmitted the stress from the unaffected side to the superior part of the affected side, but also increased the stress transmission throughout the sacroiliac joint. On the thick SA bone, strong nails could be used for better fixation. Conclusions SA external fixation can effectively restore the anterior stability of the pelvis, and benefits reconstruction of the posterior stability of the sacroiliac joint. Since overall biomechanical properties of SA external fixation are superior to those of the traditional IW bracket, SA fixation is better than IW one for Tile Bl pelvic fractures.