【作者】 王远政；

【导师】 邓忠良；

【作者基本信息】 重庆医科大学 ， 外科学， 2013， 博士

【摘要】 下颈椎（C3～C7）疾病严重影响了人们的生活质量，对于它在外科方面的治疗，主要达到三个目的：1、恢复颈椎的解剖序列。2、对脊髓、神经根减压。3、重建颈椎的稳定性。要实现这些目的，最有效的方法是进行颈椎手术内固定，手术方式分为前路手术和后路手术，主要根据患者疾病的手术适应症来作选择。常用的后路手术内固定方式包括棘突钢丝或椎板夹固定、Luque棒或Luque环固定、颈椎侧块螺钉固定、经关节突关节螺钉及颈椎弓根螺钉固定等。以往对于胸腰内固定方法的大量实验已经证实经椎弓根螺钉内固定较其他内固定方式相比较，其生物力学稳定性最高，因此已在临床上得到了广泛运用，近期和远期疗效观察满意。但由于颈椎椎弓根细小，毗邻的解剖结构复杂，一直未进行该内固定方式的尝试。直到1994年，Abumi等首次报道临床运用后路颈椎弓根螺钉内固定治疗下颈椎外伤、退变、畸形等疾病并获得成功，之后，越来越多的学者进行了关于后路颈椎弓根螺钉内固定的基础和临床研究，结果表明该术式螺钉抗拔出力最强，术后内固定松动、失效，内置物移位，颈椎再次失稳的发生率明显降低，而骨融合率明显升高，因此目前已被临床接受，逐渐成为一种常规术式，但研究同时也发现该术式的置钉危险性大，可能损伤椎动脉、脊髓和神经根，引起严重的并发症，因而，置钉的精确性至关重要。对于前路手术的内固定方式，目前主要采用椎体螺钉+钢板内固定系统。临床上有许多病例都需要前路多节段减压、植骨融合并重建脊柱稳定性，他们术后的植骨融合率和并发症的发生率与手术重建的脊柱稳定性关系密切，即脊柱稳定性越好，植骨融合率就越高，术后相应的近期和远期并发症就越低。然而，对颈椎三柱骨折、多节段椎体切除、椎体肿瘤或感染、或伴严重骨质疏松的患者，传统的颈椎前路椎体螺钉钢板内固定系统受到了挑战，因为椎体主要由松质骨构成，皮质骨少，螺钉和骨组织的咬合度低，.其重建的稳定性是非常有限的，常常需要增加后路内固定手术以保证颈椎的稳定性。对于上述情况，能否仅用一次前路手术，既能获得治疗成功又能免除二次后路手术带来的风险和并发症呢？为此，我们设计了一种全新的下颈椎内固定重建方法：经前路椎弓根螺钉(Anterior PedicleScrew， APS)内固定。本研究将从实体解剖学及影像解剖学观察下颈椎椎弓根的形态学特点，测量椎弓根径线和角度，统计学分析这些解剖学参数，从而在理论上证明下颈椎APS内固定技术的可行性。然后在离体标本上模拟手术置钉，术后进行影像学评估，从而验证下颈椎APS内固定技术的安全性和精确性,最后在严格把握手术适应症的条件下初步运用于临床，进一步验证下颈椎APS内固定技术的实际可操作性及临床效果、存在的问题。同时研发与该手术方法配套的专业螺钉、钢板内固定系统。目的就是为下颈椎APS内固定技术在临床上的大规模推广提供理论及实践依据。研究内容主要包括四部分：第一部分下颈椎前路椎弓根螺钉置入技术相关解剖学观察目的：观察成人下颈椎前路椎弓根螺钉置入相关的径线和角度，为该术的临床应用提供相关解剖学参数。方法：收集22具成人下颈椎（C3—C7）干燥骨标本，运用手工测量方法和CT影像学方法分别测量椎弓根最窄处的高度、宽度及内外侧皮质厚度，椎弓根中轴线长度、夹角，将所得数据进行统计学分析。在我院放射科CT室资料中随机抽取100例成人活体颈椎CT图像，用Mimics软件行三维重建，除以上参数外，还测量进钉点位置的相关数据，计算置钉参数的95%可信区间。结果：22具标本的相关径线及角度，其手工测量值与CT测量值间无统计学差异。成人活体下颈椎CT图像测量结果通过95%可信区间的计算，我们可以得出：C3、C4进钉点位于椎体正中矢状面受术椎弓根对侧2mm-3mm,距椎体上终板平面6mm-7mm,进钉角度为外倾角46°-48°，头倾角C3：-11°--12°，C4-6°--7°。C5进钉点位于椎体正中矢状面受术椎弓根同侧旁1-2mm,距椎体上终板平面7mm-8mm,进钉角度为外倾角47°-49°，头倾角1°-2°。C6、C7进钉点位于受术椎弓根同侧，正中矢状面旁4-5mm,距椎体上终板平面7.5mm-8.5mm,进钉角度为外倾角C6：40°-42°，C7：36°-38°，头倾角C6:6°-7°，C7：11°-13°。置钉长度选择30mm、32mm、34mm较为适宜，螺钉直径可选择3.5mm或4.0mm。结论：本实验证实了CT测量下颈椎前路椎弓根螺钉置入技术相关参数的准确性，同时在国内首次利用大样本研究对该技术置钉参数进行了探索。第二部分下颈椎前路椎弓根螺钉置入技术的实验研究目的：探讨下颈椎前路椎弓根螺钉置入技术的可行性。方法：取18具成人尸体正常颈椎标本，剔除其周围软组织至清楚显露椎体前壁。CT扫描后，用Mimics软件重建三维模型，并测量C3～C7个体化置钉参数，包括进钉点（即椎弓根中轴线在椎体前壁投影点）、置钉方向（螺钉在横断面和矢状面上的倾斜角度）以及螺钉长度。严格按照测量结果，直视下置入椎弓根螺钉。术后作CT扫描，评价置钉效果。结果：进针点：Ｃ3、C4位于置钉椎弓根对侧，正中矢状面旁2～3mm，距上终板6～7mm；C5～C7与置钉椎弓根同侧，其中C5位于正中矢状面旁1～2mm，距上终板7～7.5mm，C6、C7则为4～5mm和7.5～8.5mm。置钉方向：理想角度在C3、C4为外倾角46°～47°，头倾角-11°～-7°；在C5外倾角约48°，头倾角接近0°；C6、C7为36°～40°和8～13°。螺钉长度：可选择28、30、32m，其直径为3.5mm。本组共置钉144枚。术后CT示，全部螺钉均经椎体前方置入椎弓根内抵达侧块。其中，有16枚胀破椎弓根外侧皮质，3枚穿破外侧皮质（均发生在C3、C4节段）。结论：下颈椎前路椎弓根螺钉置入技术是可行的，但必须遵循个体化原则，对于一些既需经前路手术而又必须加强颈椎稳定性的病例，不失为一种可供选择的术式。第三部分下颈椎前路椎弓根螺钉内固定的初步临床应用目的：探讨颈椎前路椎弓根螺钉内固定技术临床应用的可行性和安全性。方法：作者应用下颈椎前路椎弓根螺钉内固定技术，治疗下颈椎疾患10例。术前皆行颈椎CT扫描，Mimics软件重建三维模型，测量置钉各参数（进钉点、置钉角度和螺钉长度与直径）。手术常规颈前方入路，显露椎体前壁致两侧外缘，辨清固定椎体上下终板。在X线透视引导下，严格按照术前的置钉参数置钉。术后复查颈椎正侧位片、CT平扫和三维重建、MRI，由放射科医生与非术者骨科医生共同评价。术后1、3、6、12个月随访，并进行评价。结果：术中除1枚C4和1枚C7螺钉未能成功置入外，共计置入C3-C7螺钉24枚。术后CT示，4枚损伤椎弓根外侧壁。术后，有1例一周后死于急性心肌梗死，余9例均获随访。3例创伤患者中，按Fankel分级，1例A级患者无恢复，但无加重；另2例有2-3级恢复，即其神经根激惹症状减轻或消失。6例非创伤患者，脊髓功能JOA评分平均提高到13.4分，按Hirabayashi法计算，改善率为60.7%。所有受访病人，除有2例发生吞咽困难外，余均无并发症发生。各例早期均有骨融合出现。结论：下颈椎前路椎弓根螺钉内固定技术可行，相对较为安全。置钉成功的关键，在于术前个体化置钉参数的测定及术中X线透视技术的运用。第四部分下颈椎前路椎弓根螺钉钢板系统的初步设计目的：对下颈椎椎弓根螺钉钢板系统作书面初步设计方法：在前路椎体螺钉钢板系统的基础上，根据椎弓根螺钉的需要进行设计改进，运用CAD软件绘图。结果及结论：初步设计出前路椎弓根螺钉、配套钢板及专业置钉器。更多还原

【Abstract】 The lower cervical spine (C3-C7) diseases serious impact on humanhealth, to surgical treatment of lower cervical spine diseases, the purposecan be attributed to: restore the anatomy of the cervical spine sequence,nerve root or spinal cord decompression and reconstruction of cervicalstability. Cervical internal fixation is an effective means of achievingthese objectives, the surgical approach is divided into anterior surgery andposterior surgery, mainly to make the selection according to the patient’sdisease indications for surgery. Posterior internal fixation, includinginterspinous wiring、 lamina clips Luque rods or Luque ring fixed、cervical lateral mass screw fixation, Margel screws and cervical pediclescrews, et al. For thoracolumbar fixation methods in the large number ofexperiments have been confirmed that transpedicular screw internalfixation compared with other methods, its highest biomechanical stability,has been in clinical widely used short-term and long-term efficacysatisfaction. However, due to the small cervical pedicle, adjacent to the complex anatomical structure has not been the attempt of this internalfixation. Until the the1994, Abumi first reported clinical use of theposterior pedicle screw fixation in cervical spine trauma, degenerative,deformity and obtained succession, After that, more and more scholarshave researche the posterior cervical pedicle screw fixation on basic andclinical. The results show that the technique can achieve true spinalthree-column fixation and greatest screw pull out strength, at the sametime, the incidence of internal fixation loosening、failure、implantdisplacement and instability again significantly reduced, and so far hasbeen clinically accepted gradually become a routine surgical. But thestudy also found that the risk of the surgical screw placement may damagethe vertebral artery, spinal cord and nerve roots, causing seriouscomplications, therefore, the accuracy of pedicle screws placement iscrucial.Internal fixation for anterior cervical surgery currently the mainuse vertebral screws-and-plate fixation system. Many patients haverequired multilevel anterior decompression and reconstruction in clincial,In these case,the fusion and complication rates postoperative have beenshown a direct correlation with the mechanical stability of the fixation.That great spinal stability contribute to the higher fusion rate, the lowerrate of corresponding near-term and long-term postoperativecomplications. However, in case of severe three-column subaxial cervical spine fractures, multilevels vertebral discectomies or corpectomie,vertebral body tumor or infection, especially with serious osteoporosispatients, the traditional anterior cervical vertebral screw plate fixationsystem has been challenged, because vertebral mainly composed ofcancellous bone, with a thin cortex,n so the anchorage characteristics arelower, biomechanical stability is limited. In such cases,supplementalposterior stabilization is often needed. How can these patients only sufferanterior fixation to get the same efficacy as before and reduce thecomplication risk by secondary posterior fixation? So we investigated anew way of cervical internal fixation reconstruction technique:anteriorpedicle screw(APS) fixation. Our study from the cervical pediclemorphological observation of physical anatomy and imaging anatomycharacteristics, measure the the pedicle diameter line and angle, statisticalanalysis of these anatomical parameters, which, proved theoreticallyfeasibility of cervical APS fixation techniques..Then simulated surgicalscrew placement in vitro specimens, postoperative radiographic evaluation,so as to verify the safety and accuracy of the APS technology. Finally,under strict conditions to grasp the surgery indications used in clinicalpreliminary，further validate the practical operability of the lower cervicalspine APS fixation techniques and clinical effect, existence problems.Professional R&D at the same time supporting the surgical methodsscrew plate fixation system. The purpose is to provide theoretical and practical basis for large-scale promotion APS techniques in clinical. Theresearch mainly includes four parts:PART ONE:ANTERIOR PEDICLE SCREW INSERTION FOR LOWCERVICAL SPINE: ANATOMICAL OBSERVATIONObjective：To observe the pathlines and angles related to lowercervical spine anterior pedicle screw (APS) fixation in adults so as toprovide anatomical parameters in clinics.Methods: A total of22cervical spine (C3-C7) specimens of humanadult cadavers were individually measured by hand and CT scan todetermine the height and width of the narrowest part in pedicle, thicknessof inner and outer cortexes, pedicle axis length and included angle of axesfollowed by statistical methods. One hundred pieces of CT images from CTdatabase were randomly selected, then three-dimensional modelreconstruction was performed by Mimics software, relative parameters ofscrew insertion point were measured and95%confidence interval of screwinsertion parameters was also calculated.Results: No significant difference of pathlines and anglesmeasurements of22specimens was found between manual work group andCT scan group. Basing on the calculation of measurements of adult lowercervical spines in CT images with95%confidence interval, the insertionpoints for C3and C4was2-3mm opposite from operated pedicle incentrum median plane and6-7mm from upper end-plate of centrum plane, the outside inclined angle of screw insertion was46°-48°.Craniallyinclined angles for C3and C4were-11°--12°and-6°--7°respectively.The insertion point for C5was1-2mm beside operated pedicle in centrummedian plane and7-8mm from upper end-plate of centrum plane,theoutside and cranially inclined angles of screw insertion were47°-49°and1°-2°respectively. The insertion points for C6and C7were at the same sidewith operated pedicle,4-5mm beside centrum median plane and7.5-8.5mm from upper end-plate of centrum plane. The outside inclined angles ofscrew insertion for C6and C7were40°-42°and36°-38°respectively,cranially inclined angles were6°-7°and11°-13°. For insertion screws, thelength should be30mm,32mm or34mm and the diameter should be3.5mm or4.0mm.Conclusions: This study confirms the accuracy of CT scan in themeasurement of lower cervical spine and APS fixation related parametersand makes an exploration in technical range of parameters for the first timein the country using a large sample.PART TWO:EXPERIMENTAL STUDY ON LOWER CERVICALSPINE ANTERIOR PEDICLE SCREW INSERTIONObjective：To study the feasibility of lower cervical spine anteriorpedicle screw (APS) insertion and provide basis for its clinical application,according to the preoperative APS related technological parameters, onwhich strict performance was based. Methods：Normal cervical spine specimens of18cadavers werecarefully dissected to resect the surrounding tissue and clearly expose thecentrum antetheca. Following the CT scans, three dimensional model wasreconstructed by mimic software, the imaging data to measured keyparameters of anteroir transpedicular screw fixation by mimics software.The individual screw insertion parameters including intersection point（projective point of pedicle central axis on centrum antetheca）, insertionangle(the inclined angle of screws in cross-sectional and sagittal plane ofcentrum) and screws length of C3–C7were measured. Under direct vision,we strictly inserted pedicle screws according to the measurements resultsand evaluated efficacy by postoperative CT scans. Results The insertionpoints for C3and C4was2-3mm beside centrum median plane and in theopposite of operated pedicle,6-7mm from upper end-plate of centrumplane. The insertion points for C3-C7were in the same side of operatedpedicle, point for C5was1-2mm beside centrum median plane and7-7.5mm from upper end-plate of centrum plane. These parameters for C6andC7were4-5mm and7.5-8.5mm respectively. The screw insertiondirection was outside inclined in cross-sectional plane, and craniallyinclined in sagittal plane. The favorable outside inclined angles for C3orC4, C5and C6or C7were46°-47°,48°and36°-40respectively, craniallyinclined angles for them were-11°-7°,0°and8°-13°respectively. Thescrew length could be choosed among28mm,30mm and32mm, the screw diameter should be3.5mm. Basing on the relative measurements,we finally inserted144screws. Postoperative CT showed that all screwshave arrived lateral side via anterior insertion into pedicle inside, but therewere16screws exposure from pedicle lateral cortex, and3screwsperforating pedicle lateral cortex, which mostly occurred in C3and C4.Conclusion：Lower cervical spine anterior pedicle screw fixation isfeasible, the high accuracy and individuality of screw insertion are required.The APS could be applied for patients who need anterior approachoperation and strong fixation, it’s a alternative procedure.PART THREE:PRELIMINARY CLINICAL APPLICATION OFANTERIOR PEDICLE SCREW FIXATION OF LOWER CERVICALSPINEObjective：To discuss the feasibility and safety of anterior pediclescrew fixation in treatment of low cervical diseases.Methods： A total of10cases of low cervical diseases were treatedwith anterior pedicle screw (APS) fixation by us. All patients receivedpreoperative cervical CT scans, three-dimensional model reconstruction bymimics software and measurement of screw placementparameters(insertion point screw placement angle screw length anddiameter). All APS were performed through cervical anterior approach,then centrums antetheca and bilateral outer edges were exposed todistinguish and fix vertebral end plates, all were strictly operated under the fluoroscope assistance and preoperative measurements to insert screws.The postoperative efficacy of APS was evaluated by radiologist and otherorthopedist via anteroposterior and lateral radiation, CT scans, MRI, andthree-dimensional model reconstruction. A follow-up visit was did1,3,6and12months after operation.Results： Besides1screw for C4and1for C7,24screws for C3-C7were successfully inserted. Postoperative CT scans demonstrated4screwsbreaking outer vertebral wall. Besides1case suddenly dying from acutemyocardial infarction1week after operation, other9cases sufferedfollow-up visit. In3cases of trauma,1case did not get improvment butwith no aggravation according to Fankel grade. Other2cases achieved2ndand3rdgrade improvement with symptoms of nerve root irritationdisappearance or alleviation. Among6cases of non-trauma, spinal functionscore by JOA was averagely elevated to13.4scores, and the rate ofimprovement was60.7%according to Hirabayashi method. There was noserious complication except for2cases of dysphagia among all patients.Conclusion： Lower cervical spine anterior pedicle screw fixation isfeasible and relatively safe. The keys to success are preoperativemeasurement of individualized screw insertion parameters and appropriateapplication of intraoperative fluoroscope assistance. PART FOUR:PRELIMINARY DESIGN OF ANTERIOR PEDICLESCREW FIXATION SYSTEM IN LOWER CERVICAL SPINEObjective: a draft preliminary design of lower cervical pedicle screwplate systemMethods: based on the road of vertebral screw plate system, inaccordance with the needs of the pedicle screw design improvements, useCAD software to draw.Results and conclusions: preliminary design the anterior pediclescrews supporting plate and the professional set staple removers.更多还原