经寰椎"椎弓根"螺钉内固定技术的临床应用

目的：探讨经寰椎“椎弓根”螺钉内固定技术的手术可操作性和临床疗效。方法：对42例寰枢椎脱位并有高位颈脊髓受压症状及体征的患者应用经寰椎“椎弓根”螺钉内固定技术治疗，术前均行X线、CT等影像学检查；术中在直视下行C1、C2置钉，复位固定，椎板后弓植骨。其中16例难复性寰枢椎脱位采用经口腔前路松解，一期后路经寰椎“椎弓根”螺钉复位固定融合。术后颈托固定3个月。结果：42例84枚螺钉均成功置入，复位固定满意。术后36例获3-42个月随访，平均18．6个月，患者均在3～6个月寰枢椎骨性融合，未发现螺钉松动、断钉和寰枢椎再移位现象。其中4枚螺钉穿入椎动脉孔内缘1mm，但无椎动脉损伤的临床表现。31例患者脊髓功能明显改善，5例好转。结论：经寰椎“椎弓根”螺钉内固定技术具有直视下置钉、短节段固定、术中复位、融合率高等特点，为寰枢椎脱位患者的治疗提供了一种较好的内固定术式。     

Cortical bone thickening in Type A posterior atlas arch defects: experimental report

Background Context

To date, no information about the cortical bone microstructural properties in atlas vertebrae with posterior arch defects has been reported.

Evaluation of anatomic landmarks and safe zones for screw placement in the atlas via the posterior arch

Several studies have evaluated quantitative anatomic data for direct lateral mass screw fixation. To analyze anatomic landmarks and safe zones for optimal screw placement through the posterior arc of the human atlas, morphometric parameters of 41 adult native human atlas specimens were quantitatively measured. Internal dimensions of the atlas (lateral mass, maximum and minimum intraosseous screw length), minimum height and width of the posterior arc and optimal screw insertion angles were defined on pQCT scans. By this, an optimal posterior screw insertion point (OIP) and a preferable screw direction (PSD) through the posterior arch into the lateral mass of C1 were defined. External dimensions (transverse and sagittal diameter) as well as the width of the mid-portion of C1 lateral mass were significantly higher in male specimens. The mean height of the posterior arch at the vertebral artery groove was 4.1 ± 0.8 mm in female and 4.6 ± 0.9 mm in male specimens. The optimal screw insertion point was located 21.6 ± 1.7 mm in female and 23.6 ± 2.3 mm in male lateral from the posterior tubercle of C1 (P < 0.01). The preferable screw direction was a mean medial inclination of 7.9 ± 1.9° in female and 7.3 ± 2.7° in male specimens and a mean rostral direction of 2.4 ± 1.8° in female and 3.1 ± 1.7° in male specimens. In conclusion, the presented study provides information for the use and design of upper cervical spine instrumentation techniques, such as screw placement to C1 via the posterior arch. The characterization of working areas and safe zones (OIP, PSD) might contribute to a minimization of screw malposition in this highly demanding instrumentation technique.     

国人寰椎定量解剖研究及螺钉置入的安全性探讨

目的:观察和测量国人寰椎以获取形态学参数,为临床治疗提供科学证据,减少相关手术并发症。方法:用电子游标卡尺和量角器测量48套正常成年人寰椎新鲜标本的相关参数,包括寰椎前弓宽度(AW)、寰椎前弓与侧块相连处厚度(AD)、后弓椎动脉沟最窄处骨内的高度(ITG)、后弓椎动脉沟最窄处外缘的高度(OTG)、侧块中点高度(MHL)和侧块宽度(LW)、寰椎侧块外倾角(α),并进行统计学分析。结果:AW平均为(20.45±1.53)mm;AD男性左侧平均为(3.91±1.32)mm,右侧平均为(4.11±1.42)mm,女性左侧平均为(3.72±1.61)mm,右侧平均为(3.82±1.53)mm;ITG男性左侧平均为(2.46±1.57)mm,右侧平均为(2.41±1.65)mm,女性左侧平均为(2.36±1.57)mm,右侧平均为(2.32±1.65)mm;OTG男性左侧平均为(4.76±2.26)mm,右侧平均为(4.64±1.70)mm,女性左侧平均为(4.55±2.26)mm,右侧平均为(4.53±1.30)mm;MHL平均为13.68mm;LW平均为12.98mm;α平均为25°。结论:手术时必须考虑到个体、性别、左右差异。术中禁忌盲目操作以免造成椎动脉、神经根及脊髓损伤。由于寰椎椎弓根螺钉和寰椎侧块螺钉进钉点不同,使得寰椎椎弓根螺钉的长度较寰椎侧块螺钉要长。     

寰椎经后弓侧块螺钉固定通道的CT测量

目的:提供国人寰椎CT测量的数据,探讨寰椎经后弓侧块行螺钉置钉的可行性。方法:采用50具寰椎骨标本,对经寰椎后弓侧块的螺钉固定通道进行多个切面的CT断层扫描并测量。结果:将寰椎后结节中点旁开18～20mm的矢状面与后弓下缘上方2mm处的水平面的交线在后弓后方的投影点确定为进钉点;进钉方向保持与冠状面垂直,在矢状面上钉尖向头侧倾斜约5°,是寰椎经后弓侧块螺钉固定较理想的置钉通道。结论:寰椎具备行经后弓侧块螺钉内固定的条件。     

Aplasia of the posterior arc of the atlas with persistent posterior tubercle: a case report

An unusual case of partial aplasia of the posterior arc of the atlas, with persistent posterior tubercle, is presented in a previously healthy individual who sustained a neck trauma. Both plain X-rays and CT findings specified the lesion. Dynamic X-rays in flexion and extension showed an immobile posterior tubercle. The patient did not develop neurological symptoms at any stage during follow-up (1 year).     

寰椎椎弓根进钉通道的数字解剖学研究

目的:探讨寰椎椎弓根进钉通道在矢状面角(SSA)为0°时不同水平面角(TSA)方向投影的变化规律。方法:将20例健康成年志愿者(男12例,女8例;年龄24~68岁,平均45岁)的寰椎CT连续断层扫描数据导入Mimics 10.01软件,三维重建寰椎数字解剖模型,将重建的结果以.stl格式保存,再将寰椎数字模型导入UG Imageware 12.0,建立寰椎椎弓根进钉通道数字化分析方法,确定三维参考平面,分析在SSA为0°时左右椎弓根TSA分别从0°～30°,均匀间隔5°,观察280个寰椎椎弓根进钉通道的长度和内切圆半径的变化规律。结果:280个寰椎椎弓根进钉通道的长度为20.54～33.21mm,其中11个通道长度小于最短椎弓根螺钉长度(22mm);TSA为0°进钉时左右通道长度均最大,左右侧比较无显著性差异(P0.05),5°～30°进钉时同一进钉角度左右侧比较有显著性差异(P0.05);同侧不同进钉角度比较无显著性差异(P0.05)。280个寰椎椎弓根螺钉通道的内切圆半径为1.38～2.51mm,其中有42个内切圆半径小于最小椎弓根螺钉半径(1.75mm);同一进钉角度右侧内切圆半径与左侧比较及同侧不同进钉角度比较均无显著性差异(P0.05)。结论:不同个体甚至同一个体的左右两侧椎弓根形态之间有较大差异。部分寰椎椎弓根进钉通道长度和内切圆半径小于椎弓根螺钉最小长度和最小半径,椎弓根进钉通道内切圆半径小于最小椎弓根螺钉半径时置钉会穿破椎弓根的皮质骨,不适合采用经寰椎椎弓根螺钉内固定技术。术前用数字化技术测量寰椎椎弓根进钉通道可以实现个体化置钉。     

Shape change in the atlas with congenital midline non-union of its posterior arch: a morphometric geometric study

Background Context

The congenital midline non-union of the posterior arch of the atlas is a developmental variant present at a frequency ranging from 0.7% to 3.9%. Most of the reported cases correspond to incidental findings during routine medical examination. In cases of posterior non-union, hypertrophy of the anterior arch and cortical bone thickening of the posterior arches have been observed and interpreted as adaptive responses of the atlas to increased mechanical stress.

Anatomic variations in sensory innervation of the hand and digits

Anatomic dissections under microscopic magnification were performed on 30 fresh cadaveric hands to depict the course and interconnections of the sensory nerves to the digits. The dissections included the median nerve, the ulnar nerve, the superficial branch of the radial nerve, the dorsal branch of the ulnar nerve, and the dorsal branch of the proper digital nerve. The communicating branches between the median and ulnar nerves in the palm were found in 20 of the 30 (67%) specimens. The dorsal branch of the proper digital nerve was found to arise at or proximal to the A1 pulley zone in 62% of the long digits, more proximally than previously reported. The dorsal sensory nerves (the terminal branch of radial or ulnar sensory nerves) extending to the nail bed area were found in 46% of the digits, thus confirming that sensory supply to the dorsum of the distal phalanx and nail bed also arises from the dorsal sensory nerves. Four types of palmar-dorsal interconnections, located in the middle of the proximal phalanx, were found in the digits but not in the thumb. The presence of these branches indicates dual innervation of the dorsal and palmar side of the distal areas of the digits. These anatomic findings may help hand surgeons interpret discrepancies in sensory loss after either dorsal or palmar injuries.     

寰椎后桥X线观察及临床意义分析

目的 分析寰椎后桥X线片表现及临床意义.方法 收集我院自2002年2月至2009年6月所摄371例颈椎X线片,发现寰椎后桥57例,发生率为15.3%.分析寰椎后桥与相关临床表现的关系.结果 57例寰椎后桥X线片显示全环型31例(单侧桥板23例,双侧桥板8例),半环型26例.57例中伴颈椎椎体失稳者17例,伴颈椎退行性变者37例,有寰椎椎动脉沟环而颈椎X线片未见异常者3例.结论 寰椎后桥是一种先天性解剖变异,它与临床症状之间无明显关系.     

后路板-棒内固定系统治疗不稳定性寰椎骨折的生物力学研究

目的 :测试后路板-棒内固定系统治疗不稳定寰椎骨折的稳定性,为临床使用提供理论基础。方法 :采集新鲜成年人尸体颈椎骨(C0~C3)标本6具,用聚甲基丙烯酸甲酯(PMMA)上下包埋,在生物力学实验机上,以150N为最大生理载荷,最大力矩为1.50N·m,依次测量完整模型组(A组)、骨折模型组(B组,包括寰椎后弓两处骨折与典型Jefferson骨折,分别作为B1组和B2组,骨折模型制作时保持横韧带完整)、内固定模型组(C组,包括B1组+内固定系统、B2组+内固定系统,分别作为C1组、C2组)C0-C1、C1-C2节段前屈/后伸、左/右侧屈和左/右旋转等6个方向的三维运动范围(ROM),通过比较,评价后路板-棒内固定系统治疗寰椎骨折的生物力学稳定性。根据测量所得ROM值,设A组各方向三维运动稳定性指数(Sf)为100%,计算B组、C组模型各运动方向Sf,进一步直观比较各模型的稳定性变化。结果:C0-C1节段,A组前屈/后伸、左右侧屈、左右轴向旋转方向的ROM分别为11.06°±1.00°,7.08°±0.62°,13.24°±1.24°;B1、B2组前屈/后伸、左右侧屈、左右轴向旋转方向ROM均较A组明显增大(P0.05);C1组前屈/后伸、左右侧屈、左右旋转方向的ROM均较B1组明显减小(P0.05);C2组各方向ROM均较B2组明显减小(P0.05);C1、C2组前屈/后伸、左右侧屈、左右轴向旋转方向ROM与A组比较均无统计学差异(P0.05)。C1-C2节段,A组前屈/后伸、左右侧屈、左右轴向旋转方向的ROM分别为10.07°±1.12°,5.56°±0.54°,20.83°±2.12°;B1、B2组各方向ROM均较A组明显增大(P0.05);C1组各方向的ROM较B1组明显减小(P0.05);C2组各方向ROM较B2组明显减小(P0.05);C1、C2组各方向ROM与A组比较均无统计学差异(P0.05)。C0-C1节段,B1组前屈/后伸、左/右侧屈、左/右轴向旋转方向Sf分别为71%、70%、64%,B2组各方向Sf分别为61%、55%、58%,C1组各方向Sf分别为102%、108%、108%,C2组各方向Sf分别为91%、91%、92%。C1-C2节段,B1组前屈/后伸、左/右侧屈、左/右轴向旋转方向Sf分别为70%、61%、35%,B2组各方向Sf分别为59%、54%、37%,C1组各方向Sf分别为105%、111%、106%,C2组各方向Sf分别为91%、90%、92%。结论:寰椎后路板-棒内固定系统既能恢复上颈椎稳定性,又可保留其生理运动功能。使用该系统治疗寰椎后弓两处骨折,在稳定性方面效果稍优于典型Jefferson骨折。     

Congenital Anomaly of the Atlas Misdiagnosed as Posterior Arch Fracture of the Atlas and Atlantoaxial Subluxation

Partial or complete absence of the posterior arch of the atlas is a well-documented anomaly but a relatively rare condition. This condition is usually asymptomatic so most are diagnosed incidentally. There have been a few documented cases of congenital defects of the posterior arch of the atlas combined with atlantoaxial subluxation. We report a very rare case of congenital anomaly of the atlas combined with atlantoaxial subluxation, that can be misdiagnosed as posterior arch fracture.     

胆囊管解剖变异的诊断及其临床意义

目的　探讨胆囊管的解剖变异的诊断及其在胆囊切除术中的意义。方法　回顾性分析我院连续 5 0 0例胆囊切除术时所发现的 5 2例胆囊管变异 ,对其病理类型和手术处理技巧进行讨论。结果　术前ERCP、MRCP所发现的胆囊管变异与手术证实的胆囊管变异有高度的一致性(Kappa值分别为 0 .815和 0 .868,P <0 .0 0 1)。胆囊管低位汇入肝总管下端者合并胆总管结石显著高于其他类型胆囊管变异者 (P <0 .0 0 1) ;术中医源性胆道损伤 4例 ,皆发生在有胆囊管变异的患者 ,其发生率显著高于无胆囊管变异的患者 ,全组无死亡病例。结论　术前酌情选用ERCP或MRCP ,可发现胆囊管变异 ,并有较高的准确性。术中探查及必要的术中胆道造影和胆道镜是发现和处理胆囊管变异的最好方法     

Hypertrophy of the anterior arch of the atlas associated with congenital nonunion of the posterior arch: a retrospective case-control study

Background contextNonunion of the posterior arch of the atlas is an uncommon but normal developmental variant. It is usually asymptomatic in the patient but may be associated with greater incidence of fracture because of increased stress on the anterior arch.PurposeWe sought to determine whether anterior arch hypertrophy is present in cases of congenital nonunion of the posterior arch of the atlas.Study design/settingA retrospective analysis of 1 year (February 2005–January 2006) of computed tomography cervical spine studies requested by the University of California San Diego Medical Center Trauma Department was undertaken.Patient sampleAll patients matching the search criteria (see Study design) were included.Outcome measuresArea density product, defined as the midline cross-sectional area of the anterior arch on sagittal reformat multiplied by the average areal radiodensity in Hounsfield units (HU) as measured by two raters, was calculated for cases and controls.MethodsCases of posterior arch nonunion were identified and matched to controls. The significance of differences in area density product between cases and controls were established by the Student t test. Interrater correlation was calculated.ResultsPosterior arch nonunion was identified in 26 individuals (3.1% of 839 studies reviewed). Compared with age- and sex-matched controls, a 21% increase in area density product of the midline anterior arch was observed in posterior arch nonunion cases (773 HU-cm² in cases vs. 637 HU-cm² in controls; p<.001). This increase was attributable to a 21% increase in cross-sectional area (1.05 cm² in cases vs. 0.87 cm² in controls; p<.002). In contrast, there was no significant difference with regard to increased average radiodensity.ConclusionsIt has long been subjectively recognized but not objectively quantified, until the present study, that the anterior arch of the atlas is hypertrophied in cases of posterior arch nonunion. Anterior arch hypertrophy may represent an adaptive response to chronically elevated mechanical stress and loss of hoop strength in cases of posterior nonunion.     

寰椎椎弓根螺钉固定技术的改进研究

目的 探讨寰椎椎弓根螺钉的置钉方法. 方法 以电子游标卡尺测量48具干燥寰椎标本的相关解剖学数据;并依据寰椎椎弓根的形态对寰椎进行分类,提出了针对不同类型寰椎的各种椎弓根螺钉置钉方法. 结果 钉道处椎动脉沟底骨质厚度小于螺钉直径3.5mm的占16.7%(8/48),其中4.2%(2/48)厚度小于螺钉半径1.75mm.将寰椎分为普遍型(占83%)、轻度变异型(占13%)和重度变异型(占4%). 结论 对于寰椎后弓高度偏小的患者,可以部分经寰椎后弓或跨越寰椎后弓实现寰椎的椎弓根螺钉固定,进钉位置的确定应以术前三维CT重建和术中探查结合考虑.     

骶2椎弓根置钉的应用解剖学研究

目的:研究第一骶后孔和骶外侧嵴与S2椎弓根的位置关系,建立以第一骶后孔和骶外侧嵴为解刮标志的S2椎弓根置钉定位技术.方法:取15具成人干燥骶骨标本,分别从S1、S2和S2、S3椎体融合遗迹(骶横线)处平行骶骨底平面截断骶骨,观察S2椎弓根的形态及第一骶后孔与椎弓根的关系;在平分S2椎弓根处平行骶骨底平面截断骶骨,观察S2椎弓根及其与骶外侧嵴的关系.在S2椎弓根前部(即盆面),平行骶骨底平分椎弓根的平面与骶前孔内侧缘连线的交点为a点,与正中矢状面的交点为b点.测量骶外侧嵴(S点)与a、b两点连线即sa线、sb线与正中矢状面夹角A角、B角及sa、sb的长度(Sa和sb分别代表螺钉最小和最大长度,A角和B角分别代表螺钉在水平面上与正中矢状面的最小和最大央角).从椎管最外侧的一点P向sa线及sb线引垂线,与sa及sb的交点分别为h1和h2,测量Ph1和Ph2(螺钉最大半径)的长度.第一骶后孔下缘最低点(W)与第二骶后孔上缘最高点(Y)连线为WY,平分椎弓根的平面与WY线的交点为O(螺钉在骶骨后方进钉点),测量WO的距离,O点在W的下方时为正值,O点存W的上方时为负值.在10具成人尸体标本上观察骶骨前血管神经的毗邻关系,并按照上述的测量结果置入S2椎弓根螺钉,使螺钉穿出骶骨前方,观察螺钉的出钉点的位置,结果:S2椎弓根从后外走向前内,呈扇形,后宽前窄、WO的距离为0±1.42mm,椎弓根的中轴平面通过第一骶后孔下缘最低点W,经过两侧W点画一水平线,此线与两侧骶外侧嵴的交点可作为S2椎弓根置钉的进钉点,其进钉角度在矢状面上与骶骨底平行.A角平均为30.23°(270°～33°),B角平均为45.73°(40°～51°);sa平均为27.53mm(26.60～28.14mm),sb平均为35.46mm(34.84～36.04mm);Ph1平均为9.55mm(3.98～5.20mm),Ph2平均为4.53mm(3.94～5.10mm).螺钉在水平面上与正中失状面夹角应为30.23°～45.73°;螺钉的长度为27.53～35.46mm;螺钉的直径只要小于2倍Ph2即可,即小于9.06mm.在骶骨前方骶交感干和骶正中动脉之间存在安全区域,尸体标本置入的20枚螺钉出钉点均位于此安全区域内.结论:第一骶后孔和骶外侧嵴与S2椎弓根间存在较恒定的解剖位置关系,第一骶后孔和骶外侧嵴可作为术巾判断S2椎弓根位置和S2椎弓根置钉进钉点的解剖学标志.此种置钉方法的螺钉出钉点能落在骶骨前的安全区域.     

寰椎测量及其经后弓侧块螺钉固定通道的研究

目的：提供国人寰椎的数据，探讨经寰椎后弓侧块（类似椎弓根）螺钉固定的可行性。方法：用游标卡尺对50例干燥寰椎标本进行测量。在实验研究的基础上，对5例寰枢椎不稳患者采用经寰椎后弓侧块螺钉和枢椎椎弓根螺钉加钢板内固定，术中用卡尺和量角器测量寰椎后弓进钉点及进钉方向，术后在X光片和CT片上测量经寰椎后弓侧块螺钉通道。结果：测量得出寰椎后弓、侧块、椎动脉沟、后弓进钉点、后弓侧块螺钉通道的轴线长度及进钉方向等参数。临床5例10枚经寰椎后弓侧块螺钉均准确置入寰椎内，无穿破骨皮质或损伤神经血管病例。结论：寰椎具备行经后弓侧块螺钉内固定的条件。     

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...     

Monostotic fibrous dysplasia of the spine: report of a case involving a cervical vertebra

Monostotic fibrous dysplasia of the spine is a rare entity. Only 26 cases, of which 11 were located in the cervical spine, are to be found in the literature. We report a 56-year-old male patient with cervicobrachialgia of half year’s duration. Radiographs showed a diffuse destruction of the vertebral body and the spinous process of C₄. A biopsy of the spinous process confirmed histopathologically a fibrous dysplasia. Due to minor symptoms, no surgical treatment was performed or is planned unless in case of increasing pain, an acute instability or neurological symptoms.