Anatomic comparison of transarticular screws with latera 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.     

The anatomic relation of lateral mass screws to the spinal nerves. A comparison of the Magerl, Anderson, and An techniques.

STUDY DESIGN: Analysis of the anatomic relation of the Magerl, Anderson, and An screws to the spinal nerve. OBJECTIVES: To compare the potential incidence of nerve root (ventral and dorsal ramus) injury caused by the Magerl, Anderson, and An techniques. SUMMARY OF BACKGROUND DATA: Posterior plating with lateral mass screw fixation is a common procedure for managing an unstable cervical spine. Comparative study of the Roy-Camille and Magerl techniques has been reported. However, the risk of nerve root injury for the Anderson and An techniques is not known. METHODS: Three lateral mass screw insertion techniques were performed in this study: Magerl, Anderson, and An. Each technique involved two specimens and 20 screws inserted from C3 through C7. A 20-mm-long screw was 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 violation was significantly higher with the Magerl (95%) and Anderson (90%) techniques than with the An (60%) technique (P < 0.05). The largest percentages of nerve violation for the Magerl, Anderson, and An screws were found at the dorsal ramus (50%), the bifurcation of the ventral dorsal ramus (45%), and the ventral ramus (55%), respectively. CONCLUSIONS: The results of this study indicate that the potential risk of nerve root violation is higher with the Magerl and Anderson techniques than with the An technique.     

下颈椎经关节螺钉联合侧块或椎弓根螺钉固定的效果

目的 探讨在下颈椎经颈后正中入路应用经关节螺钉联合侧块螺钉或椎弓根螺钉行内固定治疗的固定效果.方法 2003年2月至2007年10月,对22例患者通过后路应用经关节螺钉联合侧块螺钉或椎弓根螺钉行内固定治疗,男14例,女8例;年龄24～73岁,平均43岁.其中下颈椎创伤性骨折脱位13例,颈椎后纵韧带骨化症4例,颈椎管狭窄伴Ⅱ型齿突骨折1例,颈椎间盘突出伴椎管狭窄4例.结果 共置入经关节螺钉45枚,其中C4,5 2枚,C5,639枚,C6,74枚;共置入侧块螺钉12枚,C3、C4各6枚;共置入椎弓根螺钉41枚,其中C24枚,C32枚,C46枚,C721枚,T18枚.术中所有螺钉均成功置入,未出现椎动脉、神经根和脊髓损伤等置钉相关并发症.22例患者均获随访,随访时间10个月～3年8个月,平均17个月.植骨融合时间3～5个月,平均3.5个月.术后发现1例患者的2枚经关节螺钉松动,部分脱出.经加强颈托制动,术后4个月获得融合.结论 通过后路固定下颈椎时,采用经关节螺钉联合侧块螺钉或椎弓根螺钉固定,均可取得较好的固定效果.     

下颈椎经关节螺钉固定“两点法”置钉的解剖学研究

目的通过解剖学研究,获得下颈椎经关节螺钉的安全置钉方法。方法取18具颈椎标本,仔细解剖颈部的后方和前侧方,以清楚地暴露颈椎侧块,保护好脊神经前、后支（C2～8）及与周围结构的关系。确定安全进、出钉：以侧块背面中心点内侧1mm为进钉点;下位椎体上关节突的侧前方,横突与关节突相交处为出钉点。从C2/C3～C5/C6直视下通过以上2点置入克氏针,通过正侧位X线片测量克氏针在矢状面上的尾倾角、在冠状面上的外倾角及进钉深度,以确定经关节螺钉固定的进钉角度和螺钉长度,并测量经关节螺钉出钉点与脊神经前、后支和椎动脉的距离。结果实验中所有克氏针均成功置入。经关节螺钉的外倾角度为16.5°±5.1°,尾倾角度为36.6°±5.1°,钉道长度为19.0mm±1.2mm。经关节螺钉的外倾角度和尾倾角度在各节段间略有不同,但差异均无统计学意义（P〉0.05）,但钉道长度在C2/C3与C3/C4/C5/C6间差异有统计学意义（P〈0.05）。经关节螺钉出钉点与脊神经前支距离为18.2mm±2.3mm,与后支距离为7.3mm±1.4mm,与椎动脉距离为5.8mm±1.5mm,在各节段间略有不同,但差异均无统计学意义（P〉0.05）。结论使用下颈椎经关节螺钉固定技术时建议以侧块背侧中心点内侧1mm为进钉点,在矢状面上尾倾35°～40°,在冠状面上外倾15°～20°,尽量将螺钉从下位椎体上关节突的侧前方、横突后嵴与关节突连接处出钉。     

下颈椎后路3种固定技术的拔出强度研究

目的评价下颈椎后路侧块螺钉、椎弓根螺钉、经关节螺钉3种固定方法的拔出强度。方法6具新鲜颈椎尸体标本（C3～C7）,分别用侧块螺钉Roy-Camille法（LMS）、椎弓根螺钉（TPS）和经关节螺钉植入法（TAS）拧入螺钉,使用万能材料实验机,以100、200、300、400、500、600N分级加载,以18mm/min加载速度进行螺钉拔出实验,测试其最大拔出力、最大拔出能量。结果LMS最大拔出力为（426±38）N,最大拔出能量为（5.26±0.39）J;TPS最大拔出力为（502±42）N,最大拔出能量为（7.18±0.67）J;TAS最大拔出力为（482±40）N,最大拔出能量为（6.68±0.47）J。LMS的最大拔出力和最大拔出能量均小于TPS和TAS（P〈0.05）,而TPS和TAS之间相近,差异无统计学意义（P〉0.05）。结论经关节螺钉拔出强度优于侧块螺钉,而椎弓根螺钉拔出强度最大。     

Fixation strength of unicortical versus bicortical C1–C2 transarticular screws

BACKGROUND CONTEXT: The internal carotid artery and hypoglossal nerve lie over the anterior aspect of the lateral mass of the atlas and are at risk from bicortical C1-C2 transarticular screws. This has led to the recommendation for unicortical screws if the neurovascular structures are in close proximity to the proposed exit point. No data are available on strength of unicortical versus bicortical C1-C2 transarticular screws. PURPOSE: To compare the biomechanical pullout strength of unicortical versus bicortical C1-C2 transarticular screws in a cadaveric model. STUDY DESIGN: Biomechanical study. METHODS: Fifteen cervical spine specimens underwent axial pullout testing. A unicortical C1-C2 transarticular screw was placed on one side with a contralateral bicortical screw. Data were analyzed to reveal any significant differences in strength. RESULTS: Mean pullout strength for the bicortical C1-C2 transarticular screws was 1,048.8 (+/-360.1) N versus 939.2 (+/-360.6) for unicortical screws (p=.22). There was no significant difference in the pullout strength of unicortical and bicortical screws. CONCLUSIONS: In cases with satisfactory bone quality, it appears reasonable to use unicortical screws to avoid the risk of neurovascular injury from penetrating the anterior cortex of C1.     

经寰枢关节间隙螺钉和寰椎椎板钩内固定的力学稳定性

目的评价双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定的力学稳定性。方法将6具新鲜尸体颈椎标本（包括枕骨基底部和C1-C4颈椎节段）置于1．5Nm载荷下，测量C1，2节段的三维运动范围（range of motion，ROM）。标本依Gallie内固定、双侧经寰枢关节间隙螺钉和Gallie内固定、双侧经寰枢关节间隙螺钉内固定、双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定、双侧寰椎侧块螺钉和枢椎椎弓根螺钉内固定的顺序实施固定，每次固定后测量三维运动范围。结果包含经寰枢关节间隙螺钉的内固定组在旋转和侧屈方向上具有最小的ROM，其中双侧经寰枢关节间隙螺钉和寰椎椎板钩内固定组在屈伸运动方向上也具有最小的ROM。寰椎侧块螺钉和枢椎椎弓根螺钉内固定组在旋转方向上ROM大于单纯经寰枢关节间隙螺钉内固定组，但在侧屈和屈伸方向上接近经寰枢关节间隙螺钉，差异无统计学意义；其在侧屈和旋转方向上ROM均小于Gallie内固定组，差异有统计学意义。结论双侧经寰枢关节间隙螺钉和寰椎椎板钩“三点”内固定具有最强的生物力学稳定性。虽然双侧寰椎侧块螺钉和枢椎椎弓根螺钉内固定在生物力学稳定性上不及“三点”内固定，但明显优于Gallie内固定。     

Cervical and upper thoracic screwing for spinal fusion: strategy for its safe insertion to avoid major complications

There are several screwing techniques to attain cervical fusion such as pedicle screw, lateral mass screw, facet screw, transarticular and laminar screw. Each screwing technique has advantages and disadvantages. In this study, we introduce our strategy for safe screwing and its clinical results. Our strategy is as follows: lateral mass screw for C1, 3, 4, 5, 6 and pedicle screw for C2, 7, and thoracic level. When the C2 pedicle is thinner than 3.5 mm, we use C2 laminar screws. We do not use Magerl transarticular screw or facet screw; 146 screws were inserted in 17 patients. There were no major complications such as spinal cord and nerve root injury. We did not observe vertebral arterial injury either. Of the 146 screws, 141 (97.0%) were accurately inserted. As for lateral mass screwing by Roy-Camille’s technique and C2 laminar screwing, all screws were inserted in the appropriate site (100%) without any complications. Five pedicle screws were misplaced. Of the 57 pedicle screws, 5 showed a minor tear of the wall at C7, Th1 and Th3, the success rate for all pedicle screws was 91%. All showed solid fusion. For cervical screwing the most important aspect should be safety to avoid severe morbidity. Our strategy, which consists in the combined use of pedicle, lateral mass and laminar screwing, is safe and reliable.     

Posterior cervical lateral mass screw fixation: analysis of 1026 consecutive screws in 143 patients

OBJECTIVE: This study evaluates the results and complications of 1026 consecutive lateral mass screws inserted in 143 patients by a single surgeon. METHODS: Over a 50-month period, a total of 1026 lateral mass screws were placed in 143 patients ages 12-96 years (56 females and 87 males), with these records retrospectively reviewed. Screw position was evaluated by computed tomography (CT) scanning postoperatively, with screw positions assessed for facet, foraminal, or foramen transversarium violation. RESULTS: All screws were placed by a modification of the Anderson technique, but 20 screws were converted to Roy-Camille trajectories because of screw pullout. No patients experienced neural injury or vertebral artery injury as a result of screw placement. Three patients had screw pullouts using the Axis system, which did not require reoperation. Most patients had 14-mm screws placed. Postoperative CT scanning showed no compromise of the foramen transversarium or neural foramen. A total of 94 C7 lateral mass screws were placed without the need for pedicle screws at this level. Forty-four cases were performed with a screw/plate construct with the remainder performed using a polyaxial screw/rod construct. One patient had a symptomatic adjacent-level disc herniation that required surgical intervention. One patient required extension of laminectomy for residual compression. CONCLUSIONS: Lateral mass screw fixation is a safe and effective stabilization technique. This study demonstrates the safety and efficacy of lateral mass cannulation for a range of cervical pathologies with the largest reported series of consecutive lateral mass screws in the literature. In most cases of subaxial disease, nonconstrained plate/screw systems provide a reasonable alternative to polyaxial screw/rod constructs. Most patients can be fixated with 14-mm length x 3.5-mm diameter screws. The C7 lateral mass can be drilled with an adjusted trajectory.     

两种下颈椎经关节螺钉植入方法的比较研究

目的：比较两种下颈椎经关节螺钉植入方法的优缺点,提出并验证更为合理的植入方法,为临床提供参考。方法：运用8具颈椎标本随机模拟植入下颈椎经关节螺钉,植入的方法：一侧采用Takayasu法（记为A组）,另一侧采用Dalcanto法（记为B组）。A、B两组分别统计：植入时关节突关节劈裂情况;横突孔侵犯情况;植入后神经根损伤情况;未通过关节突关节的螺钉数。结果：共植入下颈椎经关节突螺钉64枚,A、B两组各32枚。A组未见下关节突劈裂;B组见下关节突关节下缘劈裂7例,外缘劈裂3例;两组中均未见上关节突劈裂。A组中发现8枚螺钉侵犯横突孔,B组未见横突孔侵犯。神经根前支损伤A组11例,B组2例;神经根后支损伤A组8例,B组9例。经观察证实A组2例未经过关节突关节,B组均经过下关节突关节。结论：Takayasu法在螺钉植入过长时易引起神经根和椎动脉损伤．而Dalcanto法在植入螺钉时易引起下关节突劈裂。     

The optimal transarticular c1-2 screw length and the location of the hypoglossal nerve

BACKGROUND: Injury to the hypoglossal nerve is a complication associated with transarticular C1-2 screw placement. This complication can be caused by a misdirected or too long screw. Little is known about the optimal screw length and its relationship to the hypoglossal nerve. METHODS: Twenty cervical spine specimens were used to study the optimal length of the transarticular C1-2 screw. Using the Magerl technique, a 3.0 mm drill bit was inserted into the C2 lateral mass, passing through the C1-2 facet joint and penetrating the upper portion of the ventral cortex of the lateral mass of the atlas. After drilling, the hole length was measured between the dorsal cortex of the C2 inferior articular process and the ventral cortex of the C1 lateral mass. In addition, six sagittal-sectioned cadavers were carefully dissected to observe the location of the hypoglossal nerve in the anterior aspect of the atlantoaxial region. RESULTS: The results of the measurements showed that the mean optimal screw path length for all specimens was 38.1 +/- 2.2 mm with a range of 34-43 mm. There was no significant difference between sexes in the screw path length (p 0.05). The hypoglossal nerve lies vertically in front of the lateral portion of the C1 lateral mass and the C1-2 facet joint. The area where the hypoglossal nerve lies is approximately 2-3 mm lateral to the middle of the anterior aspect of the C1 lateral mass. CONCLUSIONS :This study suggests that the mean optimal transarticular C1-2 screw length may be 38 mm; however, the determination of the accurate optimal C1-2 screw length should be made on an individual basis. Risk to the hypoglossal nerve can be eliminated if Magerl's technique is performed exactly.     

颈椎经关节椎弓根螺钉固定与标准椎弓根螺钉固定的生物力学比较

目的 比较颈椎经关节椎弓根螺钉固定和标准椎弓根螺钉固定的拔出强度.方法 取10具新鲜尸体颈椎标本(C_3～T_1),游离成三个颈椎运动节段(C_(3,4),C_(5,6),C_7T_1).在椎体两侧随机进行经关节椎弓根螺钉固定或标准椎弓根螺钉固定,置入直径3.5 mm皮质骨螺钉.经关节椎弓根螺钉固定以上位椎骨侧块外下象限中点为进钉点,在直视椎弓根下,螺钉在冠状面内倾约45°、矢状面尾倾约50°.由上位椎骨下关节突经关节突关节、下位椎骨的椎弓根,进入下位椎骨的椎体内.标准椎弓根螺钉固定以侧块外上象限中点为进钉点,在直视椎弓根下,螺钉方向参考CT测量结果 ,尽量与椎弓根倾斜角度保持一致,在横断面上内倾约45°、矢状面上螺钉指向椎体的上1/3.在生物力学试验机上行拔出强度试验,比较两种螺钉固定的最大轴向拔出力.结果 颈椎经关节椎弓根螺钉固定平均最大轴向拨出力为(694±42)N,标准椎弓根螺钉固定为(670±36)N,两者比较差异有统计学意义(P<0.05).结论 颈椎后路经关节椎弓根螺钉固定的拔出强度大干标准椎弓根螺钉固定,从生物力学强度方面考虑经关节椎弓根螺钉固定可以作为标准椎弓根螺钉固定的一种补充方法.     

Biomechanical comparison of occipitoatlantal screw fixation techniques

OBJECT: The stability provided by 3 occipitoatlantal fixation techniques (occiput [Oc]-C1 transarticular screws, occipital keel screws rigidly interconnected with C-1 lateral mass screws, and suboccipital/sublaminar wired contoured rod) were compared. METHODS: Seven human cadaveric specimens received transarticular screws and 7 received occipital keel-C1 lateral mass screws. All specimens later underwent contoured rod fixation. All conditions were studied with and without placement of a structural graft wired between the skull base and C-1 lamina. Specimens were loaded quasistatically using pure moments to induce flexion, extension, lateral bending, and axial rotation while recording segmental motion optoelectronically. Flexibility was measured immediately postoperatively and after 10,000 cycles of fatigue. RESULTS: Application of Oc-C1 transarticular screws, with a wired graft, reduced the mean range of motion (ROM) to 3% of normal. Occipital keel-C1 lateral mass screws (also with graft) offered less stability than transarticular screws during extension and lateral bending (p < 0.02), reducing ROM to 17% of normal. The wired contoured rod reduced motion to 31% of normal, providing significantly less stability than either screw fixation technique. Fatigue increased motion in constructs fitted with transarticular screws, keel screws/lateral mass screw constructs, and contoured wired rods, by means of 19, 5, and 26%, respectively. In all constructs, adding a structural graft significantly improved stability, but the extent depended on the loading direction. CONCLUSIONS: Assuming the presence of mild C1-2 instability, Oc-C1 transarticular screws and occipital keel-C1 lateral mass screws are approximately equivalent in performance for occipitoatlantal stabilization in promoting fusion. A posteriorly wired contoured rod is less likely to provide a good fusion environment because of less stabilizing potential and a greater likelihood of loosening with fatigue.     

The use of C1 lateral mass screws in complex cervical spine surgery: indications, techniques, and outcome in a prospective consecutive series of 25 cases

OBJECTIVES: Direct C1 lateral mass/C2 pars or pedicle screw fixation has been recently proposed as an alternative method to C1-C2 transarticular screw fixation. Although this method seems attractive, there are currently limited clinical data on the use of this technique for multilevel fixation including complex craniocervical reconstructions. The objectives of this study were to assess the safety and the clinical/radiographic outcomes in patients undergoing cervical spine surgery using C1 lateral mass screws (C1-LMS). METHODS: A prospectively accrued database was reviewed to determine initial presentation, etiology, operations, complications, and clinical/radiologic outcomes. RESULTS: Twenty-five patients with a mean age of 56 underwent fixation with C1-LMS. Mean follow-up was 12 months. The indications for using C1-LMS instead of C1-C2 transarticular screws were: unfavorable bony or vascular anatomy, tumor destruction, thoracic kyphosis or cervical hyperlordosis, inability to reduce the C1-C2 dislocation intraoperatively and or surgeon preference. Satisfactory stability was achieved in all cases with no neurologic or vascular complications. In one case, the C1 screws breached the medial cortex. Three patients developed transient postoperative C2 neuralgia. One patient had an extended stay in ICU due to respiratory issues. CONCLUSIONS: On the basis of our experience, proficiency with the use of C1-LMS screw fixation greatly enhances the ability to manage complex atlantoaxial or craniocervical pathologies with low morbidity. This technique should be considered an excellent adjunct or alternative to transarticular screw fixation.     

Computer-assisted posterior instrumentation of the cervical and cervico-thoracic spine

Posterior instrumentation of the cervical spine has become increasingly popular in recent years. Dissatisfaction with lateral mass fixation, especially at the cervico-thoracic junction, has led spine surgeons to use pedicle screws. The improved biomechanical stability of pedicle screws and transarticular C1/2 screws allows for shorter instrumentations and improves the repositioning possibilities. Nevertheless, there are potential risks of iatrogenic damage to the spinal cord, nerve roots or the vertebral artery with both techniques. Therefore, the aim of this study was to evaluate whether C1/2 transarticular screws and transpedicular screws can be applied safely and with high accuracy in the cervical spine and the cervico-thoracic junction using a computer-assisted surgery system (CAS system). Posterior instrumentation was performed using the Brainlab VectorVision System (BrainLAB , Heimstetten, Germany) in 19 patients. Surface matching was used for registration. We placed 22 transarticular screws C1/2, 31 cervical pedicle screws, 10 high thoracic pedicle screws and one lateral mass screw C1. The screw position was evaluated postoperatively using CT with multiplanar reconstruction in the screw axis of each screw. None of the transarticular screws or pedicle screws was significantly (>2 mm) misplaced and no screw-related injury to vascular, neurogenic or bony structures was observed. No screw revision was necessary. The mean operation time was 144 min (90–240 min) and the mean blood loss was 234 ml (50–800 ml). C1/2 transarticular screws, as well as transpedicular screws in the cervical spine and the cervico-thoracic junction, can be applied safely and with high accuracy using a CAS system. Computer-assisted instrumentation is recommended especially for pedicle screws at C3–C6.     

Computer navigation in dorsal instrumentation of the cervical spine--an in vitro study

Transarticular C1/2 screws are widely used in posterior cervical spine instrumentation. Pedicle screws in the cervical spine remain uncommon until now. In view of improved biomechanical stability compared to lateral mass screws, pedicle screws could be used, especially for patients with poor bone quality or defects in the anterior column. Nevertheless, there are potential risks of iatrogenic damage to the spinal cord, nerve roots, or the vertebral artery related to both techniques of posterior cervical spine instrumentation. Therefore, the aim of this study was to evaluate whether C1/2 transarticular screws as well as transpedicular screws in C3 and C4 can be applied safely and with high accuracy using a computer-assisted surgery (CAS) system. C1/2 transarticular screws as well as transpedicular screws in the cervical spine can be applied safely and with high accuracy using a CAS system in vitro. Therefore, this technique may be used in the clinical setup due to improved accuracy and reduced radiation dose for the patient and medical staff. Nevertheless, to prevent iatrogenic damage, users should be aware of known sources of possible errors that cause inaccuracies. Small pedicles with a diameter below 4.0 mm may not be suitable for pedicle screws.     

Cervical pedicle screws vs. lateral mass screws: uniplanar fatigue analysis and residual pullout strengths

BACKGROUND CONTEXT: Although successful clinical use of cervical pedicle screws has been reported, anatomical studies have shown the possibility for serious iatrogenic injury. However, there are only a limited number of reports on the biomechanical properties of these screws which evaluate the potential benefits of their application. PURPOSE: To investigate if the pull-out strengths after cyclic uniplanar loading of cervical pedicle screws are superior to lateral mass screws. STUDY DESIGN: An in vitro biomechanical study. METHODS: Twenty fresh-frozen disarticulated human vertebrae (C3-C7) were randomized to receive both a 3.5 mm cervical pedicle screw and lateral mass screw. The screws were cyclically loaded 200 times in the sagittal plane. The amount of displacement was recorded every 50 cycles. After cyclical loading, the screws were pulled and tensile load to failure was recorded. Bone density was measured in each specimen and maximum screw insertion torque was recorded for each screw. RESULTS: During loading the two screw types showed similar stability initially, however the lateral mass screws rapidly loosened compared to the pedicle screws. The rate of loosening in the lateral mass screws was widely variable, while the performance of the pedicle screws was very consistent. The pullout strengths were significantly higher for the cervical pedicle screws (1214 N vs. 332 N) and 40% failed by fracture of the pedicle rather than screw pullout. Pedicle screw pullout strengths correlated with both screw insertion torque and specimen bone density. CONCLUSIONS: Cervical pedicle screws demonstrated a significantly lower rate of loosening at the bone-screw interface, as well as higher strength after fatigue testing. These biomechanical strengths may justify their use in certain limited clinical applications.     

下颈椎经关节螺钉导向配套器械的设计与运用

目的：设计并运用下颈椎经关节螺钉导向配套器械,为临床提供帮助。方法：设计生产下颈椎经关节螺钉导向配套装置,运用2具带有头颅的颈椎标本检验,并应用于17例临床患者,植入下颈椎经关节螺钉68枚。结果：应用下颈椎经关节螺钉导向配套装置植入下颈椎经关节螺钉顺利,解剖后发现螺钉位置好,无关节突劈裂等,患者植入后经3-12个月随访,无神经受累症状,未发现螺钉松动。结论：运用下颈椎经关节螺钉导向配套器械植入下颈椎经关节螺钉,方便实用,有临床推广价值。