Anatomic comparison of transarticular screws with lateral mass screws in cervical vertebrae

Objective:To compare the potential incidence of nerve root (ventral and dorsal ramus) injury caused by cervical transarticular screws and Roy-Camille lateral mass screws. Methods:Insertion techniques with Klekamp transarticular screws and Roy-Camille lateral mass screws were respectively performed in this study. Each technique involved four specimens and 40 screws, which were inserted from C3 to C7. And 20-mm-long screws were used to overpenetrate the ventral cortex. The anterolateral aspect of the cervical spine was carefully dissected to allow observation of the screw-ramus relationship. Results : The overall percentage of nerve invasion was significantly lower with Klekamp (45 %) technique than with Roy-Camille (85%) technique (P<0.05). The largest percentage of nerve invasion for Klekamp transarticular screws was found at the dorsal ramus (25%), followed by the ventral ramus (15%) and the bifurcation of the ventral dorsal ramus (5 %). The largest percentage of nerve invasion for Roy-Camille lateral mass screws was found at the ventral ramus (80 %). Conclusion : The potential risk of nerve root invasion is lower with Klekamp transarticular screws than with Roy-Camille lateral mass screws.     

下颈椎经关节螺钉联合侧块或椎弓根螺钉固定的效果

Objective To discuss the effect of transarticular screws combined with lateral mass screws or pedicle screws through posterior approach in the lower cervical spine. Methods From February 2003 to October 2007, 22 patients were treated using transarticular screws internal fixation combined with lateral mass screws or pedicle screws in Axis plating system and Vertex system. There were cervical fracture and dislocation in 13 patients, ossification of the posterior longitudinal ligament in 4, cervical canal stenosis associated with dentoid process fracture in 1, and cervical disc herniation associated with cervical stenosis in 4 patients. Lamina or facet bone grafting were used to achieve a long-term stability, with decompression and anterior approach or not. The starting point for screw insertion was located 1 mm medial to the midpoint of the lateral mass and the direction of the screw was 40° caudally in the sagittal plane and 20° laterally in the axial plane. Results All screws insertion was successful. A total of 45 transarticular screws were inserted, with 2 in C4,5, 39 in C5,6 and 4 in C6,7. A total of 12 lateral mass screws were inserted, with 6 in C3 and 6 in C4. A total of 41 pedicle screws were inserted, with 4 in C2, 2 in C3 and 6 in C4, 21 in C7 and 8 in T1. There was no complication related to screw insertion, such as injury to the vertebral artery, nerve roots or spine cord. The follow-up period ranged from 10 months to 3 years and 8 months (mean 17 months). All cases got bone fusion. Only one instance of screw partial backout was identified, but fusion was achieved in all pa-tients. In the follow-up period, only one instance of screw partial backout was identified, but fusion was achieved in all patients. Conclusion The combined use of transarticular screws and lateral mass screws or pedicle screws fixation in the lower cervical spine can enlarge the advantages of strong stability,relatively simple, and reduce operating risk when performed appropriately.     

后外侧入路空心钉内固定治疗下胫腓后韧带止点撕脱后踝骨折

目的探讨后外侧入路空心钉内固定治疗下胫腓后韧带止点撕脱后踝骨折的疗效。方法采用后外侧入路空心钉内固定治疗26例三踝骨折中下胫腓后韧带止点撕脱后踝骨折,先行内、外踝骨折内固定,再行后踝骨折固定。结果本组均获平均15(10~24)个月随访,未出现切口感染、皮肤坏死等并发症。术后随访X线片未见内固定失败、断裂。踝关节骨折均于术后3~4个月愈合,平均3.5个月。结论后外侧入路空心钉内固定治疗下胫腓后韧带止点撕脱后踝骨折操作方便、复位精确、固定可靠,值得进一步推广。     

枢椎后路峡部螺钉固定的相关影像学测量

目的：通过CT测量探讨枢椎峡部螺钉固定技术的安全性和可行性。方法：收集2016年1月至2019年12月进行全颈椎CT检查的137例结构完整的上颈椎CT数据,其中男71例,女66例;年龄22~65（41.8±17.4）岁。通过Mimics19.0软件测量峡部螺钉技术相关的解剖学数据,包括峡部宽度、峡部垂直长度、峡部垂直高度、峡部螺钉通道长度、峡部螺钉通道头倾角度。并分析各项指标之间的相关性。结果：枢椎峡部宽度（9.05±1.63） mm,垂直长度（11.21±1.43） mm,垂直高度（17.53±2.93） mm。螺钉通道长度为（19.07±3.20） mm。峡部螺钉通道长度>14 mm的占94.53%,14~16 mm的占82.12%,16~18 mm的占63.14%,18~20 mm的占39.78%。螺钉通道的头倾角度为30°~68°,平均（46.06±8.06）°。螺钉通道长度和头倾角度呈高度正相关（r=0.965,P=0.000）。峡部垂直长度和螺钉通道长度,峡部垂直长度和螺钉的头倾角度之间都呈轻度正相关（r=0.240,P=0.000;r=0.163,P=0.007）。峡部宽度和螺钉通道长度,峡部宽度和螺钉通道的头倾角度之间都呈中度负相关（r=-0.333,P=0.000;r=-0.380,P=0.000）。结论：进行枢椎后路峡部螺钉固定安全、可靠,比枢椎后路椎弓根螺钉固定具有更大的适用范围,可以作为椎弓根螺钉的替代选择。     

后路寰椎后弓螺钉内固定研究进展

寰椎后弓螺钉内固定技术的提出,为治疗枕颈部不稳提供了新的补救方法。许多文献报道了寰椎后弓螺钉固定的可行性,初步显示了其置钉点易暴露、出血少、手术时间短等优势,尤其在侧块被肿瘤、炎症、创伤等破坏无法使用寰枢关节螺钉、寰椎侧块螺钉、椎弓根螺钉时补救固定。但如果外科医生术中操作不当,则可引起医源性骨折、椎动脉及颈脊髓损伤等严重并发症。因此,寰椎后弓螺钉内固定技术的安全性和有效性成为当下研究的热点。     

颈椎后路经关节螺钉钢板内固定术在下颈椎骨折脱位中的应用

目的探讨后路经关节螺钉钢板固定在下颈椎骨折脱位中的临床应用。方法2003年2月-2006年5月,对22例严重下颈椎骨折脱位采用后路经关节螺钉Axis钢板固定10例;后路联合前路减压、植骨融合、Orion钢板固定12例,共置入78枚经关节螺钉。术中运用Klek- amp经关节螺钉技术,以侧块中心点内侧1 mm为进钉点,进钉角度在矢状面上尾倾40°,在冠状面上外倾20°,行四层皮质固定。结果22例患者均获得随访,时间3个月～3年,平均15个月。术中所有螺钉均成功置入,1例患者术后第3天出现C7单侧神经根刺激症状,未予特殊处理,3个月后症状消失。没有出现椎动脉和脊髓损伤等其他置钉相关并发症。发现1例螺钉松动部分脱出,经加强颈托制动,术后3.5个月仍获得融合。其余患者均融合成功。结论下颈椎后路经关节螺钉钢板固定如使用得当,固定可靠、操作简单、相对安全。经关节螺钉钢板置入前,必须行脱位复位和小关节间植骨。     

枢椎棘突螺钉与椎弓根螺钉的解剖学比较

目的：比较枢椎棘突螺钉和椎弓根螺钉的技术难度和相关解剖学参数,探讨枢椎棘突螺钉固定的可行性和安全性。方法：自2010年2月至7月,选取10具颈椎标本,男5具,女5具,年龄45～76岁,平均60.5岁。将标本俯卧,颈部置于中立位。从C1-C3剔除颈部后侧所有的软组织,以清楚地暴露枢椎侧块和峡部。枢椎椎体左右侧任意选择进行棘突螺钉和椎弓根螺钉固定,各10枚螺钉,置入直径为4.0mm的皮质骨螺钉。枢椎棘突螺钉以枢椎棘突螺钉的进钉点选择为棘突的基底部、棘突和椎板的交界处,进钉角度水平置钉,螺钉由对侧棘突基底部穿出,形成双层皮质固定;枢椎椎弓根螺钉进钉点为枢椎下关节突根部中点,钉道方向与矢状面夹角15°～20°,与横断面夹角约30°。螺钉置入后,使用多层螺旋CT扫描机对标本进行扫描重建。测量螺钉在骨内的实际深度,记录椎弓根螺钉和棘突螺钉置钉失败、穿破椎弓根、进入椎管或置入横突孔的螺钉数目。结果：枢椎棘突螺钉和椎弓根螺钉的置入均无明显的技术困难。棘突螺钉未见螺钉置入椎管和劈裂棘突,但椎弓根螺钉有1枚螺钉突出椎弓根外侧皮质,侵犯横突孔。枢椎棘突螺钉的平均钉道长度为（21.4±1.4）mm,稍短于枢椎椎弓根螺钉的（23.7±1.0）mm,但两者间差异无统计学意义（t=-4.387,P〉0.05）。结论：枢椎棘突基底部具有螺钉固定的可行性,枢椎棘突螺钉较椎弓根螺钉固定相对安全、简单。     

下颈椎经关节螺钉钉棒系统固定的生物力学研究

目的：比较下颈椎三柱损伤后单独经关节螺钉固定（TAS）、经关节钉棒系统同定（TRS）和侧块螺钉钉棒系统固定（LRS）的三维稳定性。方法：12具新鲜颈椎标本．制成C4／5、C5／6节段三柱损伤模型，分别进行单独经关节螺钉（TAS组）、经关节螺钉钉棒系统（TRS组）和侧块螺钉钉棒系统（LRS组）三种方法固定，在非限制性和非破坏性的实验条件下测试其前屈、后伸、左右侧弯和轴向旋转运动状态的稳定性。结果：TAS组和TRS组在各方向的运动范同（ROM）和中性区（NZ）的均数均显著小于完整标本组，差异有统计学意义（P〈0．05）；LRS组在前屈、后伸、侧弯运动中的ROM和NZ与完整标本组比较有显著降低，差异有统计学意义（P〈0．05）；LRS组在旋转运动中的ROM和NZ与完整标本组比较有不同程度的降低，但差异无统计学意义（P〉0．05）。TAS、TRS在各个方向稳定性明显优于LRS组（P〈0．05）。TRS在前屈运动中的ROM和NZ与TAS组比较有所减小，但无统计学意义（P〉0．05）；在后伸、侧弯和旋转运动中，TRS组稳定性明显优于TAS组，有统计学意义（P〉0．05）。结论：在下颈椎三柱损伤选择经关节固定技术时以钉棒形式同定稳定性更好。     

胸椎后路经关节肋骨螺钉固定技术的提出及其解剖学研究

脊柱后路经关节内同定技术具有悠久的应用历史[1-6].我们在国内外首次提出胸椎后路经关节肋骨螺钉固定(transarticular rib screw,TARS),并通过胸椎标本的实际置钉探索这项技术的解剖学可行性及其临床意义,报告如下.     

经枢椎椎板关节突关节螺钉固定的解剖学研究

枢椎承上启下,在解剖学上异于其他颈椎,具有更厚的椎板[1].目前临床常用的楸椎固定技术包括枢椎椎弓根螺钉、侧块螺钉、经C1,2关节螺钉.某些患者由于枢椎横突孔过大、枢椎峡部过小、短颈后凸畸形、单侧椎动脉畸形等解剖因素,使以上技术无法使用[2].