枢椎椎板螺钉治疗上颈椎不稳的临床研究

目的探讨枢椎椎板螺钉技术的临床应用和适应证。方法2004年10月至2008年12月,采用后路枢椎椎板螺钉技术治疗上颈椎不稳35例,男19例,女16例;年龄23～73岁,平均45岁。AndersonⅡ型和Ⅲ型齿突骨折19例,寰椎横韧带断裂1例,先天性游离齿突并寰枢椎不稳2例,寰椎骨折合并寰枢椎不稳7例,不典型Hangman骨折并C2-3不稳1例,C2-3创伤性不稳5例。患者均采用颈椎后路Vertex钉棒系统固定。结果35例患者共置入枢椎椎板螺钉68枚,术中无一例发生脊髓和椎动脉损伤。患者均获得随访,随访时间6个月～4年,平均25.5个月。随访时X线片均未见明显颈椎不稳、内固定失败及螺钉松动退出。11例患者螺钉穿出椎板背侧,但无症状出现。结论枢椎后路经椎板螺钉技术固定牢固,操作简单,相对安全,特别适用于C2椎弓根发育异常或骨折不能采用椎弓跟固定的患者。     

寰椎椎弓根螺钉及枢椎椎板螺钉固定植骨融合治疗创伤性上颈椎不稳

目的:探讨寰椎椎弓根螺钉及枢椎椎板螺钉固定、植骨融合治疗创伤性上颈椎不稳的临床疗效。方法:2005年10月至2008年6月,采用后路寰椎椎弓根螺钉及枢椎椎板螺钉或椎弓根螺钉固定技术治疗创伤性上颈椎不稳患者43例,其中枢椎椎板螺钉固定组(A组)21例,枢椎椎弓根螺钉固定组(B组)22例。所有患者均有寰枢椎半脱位或不稳,表现为不同程度的颈枕区疼痛,活动受限。均使用颈椎后路Vertex钉棒系统固定。对比两组的手术时间、术中出血量,有无神经、血管、脊髓损伤和内固定松动、断裂失败并发症,是否出现复位丢失和植骨融合率。结果:A组手术时间1～3h,平均1.5h,出血量100～650ml,平均240ml。B组手术时间1.2～3h,平均2h,出血量120～800ml,平均350ml。A组手术时间和术中出血量明显少于B组(P0.05)。A组有2例、B组有3例术中在剥离时损伤C1-2间静脉丛,均用明胶海绵压迫止血成功。术后CT显示B组1例单侧枢椎椎弓根螺钉部分进入横突孔,但无症状,余枢椎椎弓根螺钉和椎板螺钉均位置良好,未见椎动脉、神经损伤及脑脊液漏并发症。43例术后获12个月～3年随访,平均20.3个月,所有患者均于术后3～4个月获得骨性融合,术后X线片显示颈椎稳定,未见复位丢失,亦未见内固定松动退出或断裂。结论:对创伤性上颈椎不稳患者应用寰椎椎弓根螺钉及枢椎椎板螺钉固定不仅具有椎弓根螺钉同等的固定疗效,而且相对安全、简单,可以作为椎弓根螺钉固定的一种补充方法。     

Clinical and radiologic outcome of laminar screw at C2 and C7 for posterior instrumentation—review of 25 cases and comparison of C2 and C7 intralaminar screw fixation

BackgroundThe aim of this study is 2-fold: to analyze a clinical case series in which we used laminar screws for cervical posterior instrumentation and to describe the difference between C2 and C7 laminar screws in terms of technique and anatomy.MethodsData were obtained from 25 patients who underwent cervical posterior fixation with intralaminar screws at C2 or C7. C2 intralaminar screw instrumentation was used for 7 patients requiring occipitocervical fixation (basilar invagination [3 patients], C1 unstable bursting fracture [1 patient], C1-C2 instability with occipital assimilation [2 patients], and dystopic os odontoideum [1 patient]), 13 patients with C1-C2 instability, 1 patient with C2-C3 subluxation, and 4 patients undergoing C7 fixation due to pseudoarthrosis or cervical instability after trauma. A total of 34 laminar screws were placed including 1 thoracic laminar screw, and the patients were assessed both clinically and radiographically.ResultsThere were no instances where a screw violated the spinal canal nor any hardware fractures noted during the follow-up period. As for perioperative complications, there were 2 cases of postoperative wound infection, 1 case of dural laceration during dissection, and 2 cases of partial dorsal laminar breach. However, there was no neurologic compromise in any of the cases. The fusion success rate was 100%.ConclusionThese preliminary results support the use of intralaminar screws for posterior instrumentation at C2 and C7.     

Translaminar screws of the axis—an alternative technique for rigid screw fixation in upper cervical spine instability

C2 pedicle screws or transarticular atlantoaxial screws are technically demanding and carry an increased risk of vertebral artery injury. In up to 20% of cases, pedicle and transarticular screw placement is not possible due to a high-riding vertebral artery or very small C2 pedicles in addition to other anatomical variations. Translaminar screws have been reported to rigidly capture posterior elements of C2 and therefore appear to be a suitable alternative. We present our first experiences and clinical results with this new method in two neurosurgical spine centers. Twenty-seven adult patients were treated between 2007 and 2010 in two neurosurgical spine departments with C2 translaminar screw fixation for upper cervical spine instability of various origins (e.g., trauma, tumor, dens pseudarthrosis). Eight patients were men and 19 were women. Mean age was 68.9 years. In most cases, translaminar screws were used because of contraindications for pedicle or transarticular screws as a salvage technique. All patients were clinically assessed and had CT scans postoperatively to verify correct screw placement. Follow-up was performed with reexamination on an ambulatory basis. Mean follow-up was 7.6 months for all patients. In 27 patients, 52 translaminar screws were placed. There were no intraoperative complications. Postoperatively, we identified four screw malpositions using a new accuracy grading scale. One screw had to be revised because of violation of the spinal canal >4 mm. None of the patients had additional neurological deficits postoperatively, and all showed stable cervical conditions at follow-up. Two patients died due to causes not associated with the stabilization technique. The fusion rate for patients with C1/C2 fixation is 92.9%. Translaminar screws can be used at least as an additional technique for cases of upper cervical spine instability when pedicle screw placement is contraindicated or not possible. The current data suggest comparable biomechanical stability and fusion rates of translaminar screws to other well-known posterior fixation procedures. In addition, translaminar screw placement is technically less demanding and reduces the risk of vertebral artery injury.     

枢椎椎板螺钉在上颈椎后路固定术中的应用

目的探讨枢椎椎板螺钉固定术应用于上颈椎后路融合内固定术中的可行性。方法回顾性分析本院2012年1月—2014年12月在上颈椎后路融合固定术中采用枢椎椎板螺钉固定的19例患者资料,术中根据枢椎椎弓根是否存在缺如、细小等情况,选择置入双侧枢椎椎板螺钉或单侧枢椎椎板螺钉并对侧椎弓根螺钉,联合枕骨板螺钉和/或寰椎侧块螺钉。15例上颈椎畸形患者均有不同程度脊髓功能损害表现,日本骨科学会(JOA)评分为5~15分,平均11.5分。4例外伤性寰枢椎骨折患者有后颈部疼痛及活动障碍,疼痛视觉模拟量表(VAS)评分为2~7分,平均4.5分。术后复查患者影像学资料,观察内固定位置及植骨融合情况。结果所有手术顺利完成,未发生椎动脉、脊髓等损伤。术后复查CT,显示所有枢椎椎板螺钉位置良好,均未突破内侧皮质骨。随访时X线、CT示螺钉位置良好,无松动及断钉。所有患者术后12个月植骨均融合,上颈椎畸形患者神经功能均有不同程度改善,JOA评分为13~17分,平均15.3分。外伤性寰枢椎骨折患者颈部疼痛及活动障碍明显改善,VAS评分为0~2分,平均1.0分。结论枢椎椎板螺钉固定在上颈椎后路固定手术中方法简单安全、效果良好,对于无法行枢椎椎弓根螺钉固定的患者,枢椎椎板螺钉固定是一种安全有效的替代方法。     

Posterior fixation and fusion with atlas pedicle screw system for upper cervical diseases

Objective： To evaluate the feasibility, safety and efficacy of atlas pedicle screws system fixation and fusion for the treatment of upper cervical diseases.
Methods： Twenty-three consecutive patients with upper cervical disorders requiring stabilization, including 19 cases of atlantoaxial dislocation （4 congenital odontoid disconnections, 6 old odontoid fractures, 4 fresh odontoid fractures of Aderson Ⅱ C, 3 ruptures of the C1 transverse ligament, and 2 fractures of C1）, 2 cases of C2 tumor （instability after the resection of the tumors）, and 2 giant neurilemomas of C2-C3（instability after resection of the tumors）, were treated by posterior fixation and fusion with the atlas pedicle screw system, in which the screws were inserted through the posterior arch of C1. The operative time, bleeding volume and complications were reported. All patients were immobilized without external fixation or with rigid cervical collars for 1-3 months. All patients were followed up and evaluated with radiographs and CT.
Results： In the 23 patients, 46 C1 pedicle screws, 42 C2 pedicle screws and 6 lower cervical lateral mass screws and 2 lower cervical pedicle screws were placed. The mean operative time and bleeding volume was 2.7 hours and 490 ml respectively. No intraoperative complications were directly related to surgical technique. No neurological, vascular or infective complications were encountered. All patients were followed up for 3-36 months （average 15 months）. Firm bony fusion was documented in all patients after 3-6 months. One patient with atlas fracture showed anterior occipitocervical fusion. There was no implant failure. Conclusions： Posterior fixation and fusion of the atlas pedicle screw system is feasible and safe for the treatment of upper cervical diseases, and may be applicable to a larger number of patients.     

借助于枢椎椎板钉重建寰枢关节稳定的初步临床报告

目的 探讨以枢椎椎板置钉法完成寰枢或枕颈固定,用以治疗寰枢关节不稳的可行性.方法 对枢椎椎弓根畸形或椎动脉异位的病例以枢椎椎板置钉的方法 完成寰枢或枕颈固定.如果一侧枢椎椎弓根是大致正常的,就在该侧用椎弓根钉固定,在对侧用枢椎椎板钉固定.在寰椎以侧块螺钉固定,在枕骨以短螺钉固定.用连接棒在寰枢或枕枢间连接.在寰枢后弓间或枕骨与枢椎椎弓间植入颗粒状松质骨.结果 共完成了9个病例,其中寰枢固定2例,枕颈固定7例.使用一侧枢椎椎弓根钉固定、另一侧枢椎椎板钉固定6例,两侧均为椎板钉固定3例.9例均得到随访,随访时间4-13个月(平均9个月).所有病例均得到骨性融合.有神经症状的8例中,症状改善情况为:优3例,良1例,可2例,无变化2例.1例椎板钉进入了椎管.所有病例均没有出现脊髓和椎动脉损伤症状.结论 枢椎椎板置钉操作简便、安全,固定效果可靠.可以作为枢椎椎弓根置钉固定的后备方法 ,适用于椎弓根畸形或椎动脉异位的病例.     

枢椎经椎板螺钉联合寰椎侧块螺钉内固定术的临床应用

目的 探讨后路经枢椎椎板螺钉联合寰椎侧块螺钉固定技术治疗上颈椎不稳的临床疗效和并发症.方法 2003年10月至2006年12月,采用此技术治疗寰枢椎不稳17例,男12例,女5例;年龄34～73岁,平均42.5岁.Anderson Ⅱ型和Ⅲ型齿突骨折14例,寰椎横韧带断裂1例,先天性游离齿突并寰枢椎不稳2例.均有寰枢椎半脱位或不稳,表现为不同程度的颈枕区疼痛,活动受限.枢椎经椎板螺钉固定技术以棘突和椎板的交界处椎板头尾方向的中点为进钉点,为避免钉道的相互干扰,第1枚螺钉的进钉点通常选择枢椎椎板的偏头侧,另1枚螺钉的进钉点偏尾侧,用高速磨钻在进钉点磨去少许皮质骨开窗后,用手钻向枢椎对侧椎板钻孔,螺钉方向在直视下与椎板平面并行,并稍向枢椎椎板背侧倾斜,以确保螺钉不穿破椎板腹侧皮质侵犯椎管,宁可穿破枢椎椎板背侧皮质骨.内固定系统均使用颈椎后路Vertex钉棒系统同定.结果 术中无一例发生脊髓和椎动脉损伤.有2例患者在剥离寰椎后弓下缘时,损伤静脉丛,用明胶海绵压迫止血成功.术后CT示枢椎椎板螺钉位置良好,未见侵犯枢椎椎管和脊髓.随访术后X线片未见明显颈椎不稳、内固定失败及螺钉松动退出.结论 枢椎后路经椎板螺钉技术固定牢固,操作简单,相对安全,值得进一步推广.     

Percutaneous transarticular atlantoaxial screw fixation using a cannulated screw system and image guidance.

In 2000 a cannulated screw stabilization system for posterior cervical instrumentation was introduced in our department for use in complex cervical fixation procedures. A special feature of the system is the use of thin Kirschner wires for drilling the screw paths and then placing the self-drilling, cannulated screws securely over the wires. Percutaneous application of C1-C2 transarticular screws is possible through tubes. An optional "atlas-claw" provides additional stability in cases of C1-C2 stabilization. 17 patients (10 female, 7 male, mean age 60 years) with complex cervical disorders and instability of different origin were stabilized using the Neon System (Ulrich Co., Ulm, Germany). Pathology included atlantoaxial instability based on rheumatoid arthritis (n = 12), odontoid fracture (n = 4) and os odontoideum mobile (n = 1). Computed navigation (STN 4.0, Zeiss or vector vision spine, brain lab) was used in 14 cases. Transarticular C1-C2 screw fixation was performed in 14 cases (4 patients with direct C1 massa lateralis screw fixation), craniocervical fixation (C0-C2/C3) was done in 3 patients. Percutaneous application of the C1-C2 screws was used in 7 patients. Atlas claws were applied in 8 patients. There was one medial perforation of a C2 pedicle wall and one malposition of the screw in C2 without reaching the lateral mass of C1. After a mean follow-up of 9 months there were no hardware failures and stable fusion in those cases followed after 12 months or more. Clinical results were excellent or good in 14/16 patients. Cannulated screws are an effective alternative in complex stabilization procedures of the cervical spine. The presented system is technically comfortable and allows safe percutaneous screw application as well as inclusion of computed navigation with high accuracy.     

Complications of transpedicular screw fixation in the cervical spine

Today, posterior stabilization of the cervical spine is most frequently performed by lateral mass screws or spinous process wiring. These techniques do not always provide sufficient stability, and anterior fusion procedures are added secondarily. Recently, transpedicular screw fixation of the cervical spine has been introduced to provide a one-stage stable posterior fixation. The aim of the present prospective study is to examine if cervical pedicle screw fixation can be done by low risk and to identify potential risk factors associated with this technique. All patients stabilized by cervical transpedicular screw fixation between 1999 and 2002 were included. Cervical disorders included multisegmental degenerative instability with cervical myelopathy in 16 patients, segmental instability caused by rheumatoid arthritis in three, trauma in five and instability caused by infection in two patients. In most cases additional decompression of the spinal cord and bone graft placement were performed. Pre-operative and post-operative CT-scans (2-mm cuts) and plain X-rays served to determine changes in alignment and the position of the screws. Clinical outcome was assessed in all cases. Ninety-four cervical pedicle screws were implanted in 26 patients, most frequently at the C3 (26 screws) and C4 levels (19 screws). Radiologically 66 screws (70%) were placed correctly (maximal breach 1 mm) whereas 20 screws (21%) were misplaced with reduction of mechanical strength, slight narrowing of the vertebral artery canal (<25%) or the lateral recess without compression of neural structures. However, these misplacements were asymptomatic in all cases. Another eight screws (9%) had a critical breach. Four of them showed a narrowing of the vertebral artery canal of more then 25%, in all cases without vascular problems. Three screws passed through the intervertebral foramen, causing temporary paresis in one case and a new sensory loss in another. In the latter patient revision surgery was performed. The screw was loosened and had to be corrected. The only statistically significant risk factor was the level of surgery: all critical breaches were seen from C3 to C5. Percutaneous application of the screws reduced the risk for misplacement, although this finding was not statistically significant. There was also a remarkable learning curve. Instrumentation with cervical transpedicular screws results in very stable fixation. However, with the use of new techniques like percutaneous screw application or computerized image guidance there remains a risk for damaging nerve roots or the vertebral artery. This technique should be reserved for highly selected patients with clear indications and to highly experienced spine surgeons.     

Biomechanical comparison of two-level cervical locking posterior screw/rod and hook/rod techniques.

BACKGROUND CONTEXT: Locking posterior instrumentation in the cervical spine can be attached using 1) pedicle screws, 2) lateral mass screws, or 3) laminar hooks. This order of options is in order of decreasing technical difficulty and decreasing depth of fixation, and is thought to be in order of decreasing stability. PURPOSE: We sought to determine whether substantially different biomechanical stability can be achieved in a two-level construct using pedicle screws, lateral mass screws, or laminar hooks. Secondarily, we sought to quantify the differential and additional stability provided by an anterior plate. STUDY DESIGN: In vitro biomechanical flexibility experiment comparing three different posterior constructs for stabilizing the cervical spine after three-column injury. METHODS: Twenty-one human cadaveric cervical spines were divided into three groups. Group 1 received lateral mass screws at C5 and C6 and pedicle screws at C7; Group 2 received lateral mass screws at C5 and C6 and laminar hooks at C7; Group 3 received pedicle screws at C5, C6, and C7. Specimens were nondestructively tested intact, after a three-column two-level injury, after posterior C5-C7 rod fixation, after two-level discectomy and anterior plating, and after removing posterior fixation. Angular motion was recorded during flexion, extension, lateral bending, and axial rotation. Posterior hardware was subsequently failed by dorsal loading. RESULTS: Laminar hooks performed well in resisting flexion and extension but were less effective in resisting lateral bending and axial rotation, allowing greater range of motion (ROM) than screw constructs and allowing a significantly greater percentage of the two-level ROM to occur across the hook level than the screw level (p<.03). Adding an anterior plate significantly improved stability in all three groups. With combined hardware, Group 3 resisted axial rotation significantly worse than the other groups. Posterior instrumentation resisted lateral bending significantly better than anterior plating in all groups (p<.04) and resisted flexion and axial rotation significantly better than anterior plating in most cases. Standard deviation of the ROM was greater with anterior than with posterior fixation. There was no significant difference among groups in resistance to failure (p=.74). CONCLUSIONS: Individual pedicle screws are known to outperform lateral mass screws in terms of pullout resistance, but they offered no apparent advantage in terms of construct stability or failure of whole constructs. Larger standard deviations in anterior fixation imply more variability in the quality of fixation. In most loading modes, laminar hooks provided similar stability to lateral mass screws or pedicle screws; caudal laminar hooks are therefore an acceptable alternative posteriorly. Posterior two-level fixation is less variable and slightly more stable than anterior fixation. Combined instrumentation is significantly more stable than either anterior or posterior alone.     

单侧枢椎椎板螺钉在椎动脉变异的上颈椎不稳中的临床应用

目的：探讨后路寰椎侧块螺钉联合单侧枢椎椎板螺钉＋对侧枢椎椎弓根螺钉固定、自体双皮质骨加压植骨融合术治疗上颈椎不稳伴椎动脉变异的临床疗效。方法：2008年6月至2012年12月,行后路寰椎侧块螺钉联合单侧枢椎椎板螺钉＋对侧枢椎椎弓根螺钉固定、自体双皮质骨加压植骨融合术12例,男8例,女4例,年龄16—77岁,平均47．5岁。术前患者枕颈部活动受限伴或不伴疼痛,VAS评分0-7分,平均3．50±2．71;椎动脉造影或颈椎CTA示单侧椎动脉明显狭窄。观察术中有无神经及血管损伤;术后7d内行X线和CT检查,了解内固定位置;术后随访观察有无内固定松动、断裂失败并发症、复位丢失,以及植骨融合率等。结果：12例单侧枢椎椎板螺钉固定,术中未发生神经和椎动脉损伤。患者颈部VAS评分0．92±0．90,较术前明显减轻（P=0．01）。术后x线示12例患者颈椎序列恢复良好,CT示1例枢椎椎板腹侧皮质侵犯,余位置均良好。12例患者均获得随访,时间6个月～3年;未见内固定松动、断裂和复位丢失等并发症;术后6个月12例均骨性融合。结论：后路寰椎侧块螺钉联合单侧枢椎椎板螺钉＋对侧枢椎椎弓根螺钉固定、自体双皮质骨加压植骨融合术,既避免了传统螺钉固定椎动脉损伤的同时,又克服了部分病例双侧枢椎椎板螺钉时植骨床的不足,在保证良好力学稳定的情况下,可以取得良好的骨性融合率。单侧枢椎椎板螺钉可以作为一种安全有效的补充固定措施应用于椎动脉变异的上颈椎不稳患者中。     

颈椎椎弓根螺钉内固定技术有关问题探讨

目的　探讨经颈椎椎弓根内固定治疗颈椎病变临床常见问题及其处理方法。方法　采用AXIS内固定系统 ,经颈椎椎弓根螺钉固定技术对 4 0例颈椎病患者进行了手术治疗 ,对手术中常遇到的问题及处理方法进行总结。结果　 4 0例手术中 ,有 13例在置钉后感觉松动 ,9例在打椎弓根孔道时出血较多 ,术中正确处理后未发现神经血管症状。结论　经颈椎弓根内固定固定牢固 ,康复快 ,效果好 ,但手术中风险较大 ,处理不好 ,会出现严重的并发症。故熟悉解剖及手术操作技巧、冷静处理手术中遇到的问题非常重要。     

Laminar screw fixation of the axis

OBJECT: Laminar fixation of the axis with crossing bilateral screws has been shown to provide rigid fixation with a theoretically decreased risk of vertebral artery damage compared with C1-2 transarticular screw fixation and C-2 pedicle screw fixation. Some studies, however, have shown restricted rigidity of such screws compared with C-2 pedicle screws, and others note that anatomical variability exists within the posterior elements of the axis that may have an impact on successful placement. To elucidate the clinical impact of such screws, the authors report their experience in placing C-2 laminar screws in adult patients over a 2-year period, with emphasis on clinical outcome and technical placement. METHODS: Sixteen adult patients with cervical instability underwent posterior cervical and cervicothoracic fusion procedures at our institution with constructs involving C-2 laminar screws. Eleven patients were men and 5 were women, and they ranged in age from 28 to 84 years (mean 57 years). The reasons for fusion were degenerative disease (9 patients) and treatment of trauma (7 patients). In 14 patients (87.5%) standard translaminar screws were placed, and in 2 (12.5%) an ipsilateral trajectory was used. All patients underwent preoperative radiological evaluation of the cervical spine, including computed tomography scanning with multiplanar reconstruction to assess the posterior anatomy of C-2. Anatomical restrictions for placement of standard translaminar screws included a deeply furrowed spinous process and/or an underdeveloped midline posterior ring of the axis. In these cases, screws were placed into the corresponding lamina from the ipsilateral side, allowing bilateral screws to be oriented in a more parallel, as opposed to perpendicular, plane. All patients were followed for >2 years to record rates of fusion, instrumentation failure, and other complications. RESULTS: Thirty-two screws were placed without neurological or vascular complications. The mean follow-up duration was 27.3 months. Complications included 2 revisions, one for pseudarthrosis and the other for screw pullout, and 3 postoperative infections. CONCLUSIONS: Placement of laminar screws into the axis from the standard crossing approach or via an ipsilateral trajectory may allow a safe, effective, and durable means of including the axis in posterior cervical and cervicothoracic fusion procedures.     

组合枢椎椎板螺钉及经枢椎椎板关节突螺钉固定技术的临床应用

目的探讨组合枢椎椎板螺钉及经枢椎椎板关节突螺钉(TLFS)固定技术治疗颈椎损伤的可行性和应用价值。方法自2005年10月～2008年10月,采用枢椎椎板螺钉及经枢椎TLFS固定技术治疗颈椎损伤36例。结果本组获随访13~32个月,平均18个月。30例行自体髂骨植骨,6例行异体骨植骨,获得了良好的骨性愈合。术后CT示枢椎椎板螺钉及经枢椎TLFS位置良好,未侵犯椎管和脊髓。结论枢椎椎板螺钉及经枢椎TLFS固定技术不受C2横突孔中椎动脉的位置和C2椎弓根大小限制,避免了螺钉置入过程中损伤椎动脉的风险,所以该方法可作为传统枢椎后路螺钉固定技术的补充。     

多种寰枢椎后路钉棒固定技术的临床组合应用

目的评价3种寰椎后路螺钉固定方法和2种枢椎后路螺钉固定方法构成的钉棒组合治疗上颈椎不稳的可行性和临床效果。方法在气管插管全麻下对132例患者施行了寰枢椎后路钉棒固定技术,寰椎进行椎弓根螺钉、部分经椎弓根螺钉或侧块螺钉固定;枢椎进行椎弓根螺钉或交叉椎板螺钉固定。结果全组病例获钉棒固定,其中寰椎螺钉固定采用椎弓根螺钉224枚,部分经椎弓根螺钉36枚,侧块螺钉4枚;枢椎螺钉固定采用椎弓根螺钉240枚,椎板螺钉24枚。术中未发生椎动脉、脊髓损伤。120例患者术后获得随访3～22个月,平均8个月,临床症状得到不同程度的改善;X线片、CT复查螺钉位置良好,无松动、断钉,植骨3～6个月后均达到满意融合。结论寰椎和枢椎螺钉可进行多重组合,为上颈椎后路提供灵活多变的短节段固定,增加了钉棒固定技术的临床适用范围。     

Posterior C2 fixation using bilateral, crossing C2 laminar screws: case series and technical note

Rigid screw fixation of the axis, for either atlantoaxial fixation or for incorporation of C2 into subaxial cervical constructs, provides significant stability and excellent long-term fusion results but remains technically demanding due to the danger of injury to the vertebral artery. Anatomic variability of the foramen transversarium in the body of the axis can preclude safe transarticular C1-C2 screw placement in up to 20% of patients. Although more recent methods of C2 screw fixation with pedicle screws allow safer fixation in a higher number of patients, there remains a significant risk to the vertebral artery with C2 pedicle screw placement. The author describes a novel technique of C2 rigid screw fixation using bilateral, crossing C2 laminar screws, not previously reported in the literature, which does not place the vertebral artery at risk during C2 fixation. This technique has been successfully used by the author in cases of craniocervical and atlantoaxial fixation as well as for incorporation of C2 into subaxial fixations. The technique is illustrated, and the author's initial experience in treating 10 patients with crossing, bilateral C2 aminar screws for indications of trauma, neoplasm, pseudarthrosis, and degenerative disease is reviewed. The possible advantages of C2 fixation with C2 laminar screws are discussed.     

U型螺钉系统固定在寰枢椎不稳中的应用

目的 探讨运用U型螺钉系统（CUF）内固定治疗寰枢椎不稳的临床效果。方法 2004年1月至2005年12月,运用自行设计的CUF行C1.2椎弓根固定治疗C1不稳8例。其中枢椎齿状突骨折7例,Jefferson骨折1例,伴颈髓损伤6例。结果 术中未发生神经血管损伤,术后复查寰枢关节脱位全部纠正。CT轴位扫描,32枚椎弓根钉中有2枚钉部分进入椎管,1枚钉部分进入横突孔。3个月至2年平均6个月随访,7例达到骨性融合,无断钉断棒。结论 后路椎弓根钉系统固定是目前治疗C1.2不稳的较好装置。它具有固定牢固、能提拉复位且放置方便等特点。手术成功的关键在于准确置入椎弓根钉。借助U型螺钉提拉复位的同时,配合体位复位是必要的。     

颈椎后路“组合式”内固定治疗寰枢关节不稳或脱位的临床疗效

目的:评价颈椎后路“组合式”内固定治疗寰枢关节不稳或脱位的临床效果。方法:回顾分析因颅椎区骨发育畸形、血管变异或者常规固定方式失败而实施寰枢椎后路“组合式”内固定术患者共58例,其中男性24例,女性34例;年龄7~75岁,平均47.8±14.7岁。术前诊断寰枢关节不稳33例,寰枢关节脱位25例。合并颈脊髓功能损害者32例(JOA 8~16分,平均13.2±1.8分)。采用的内固定方式包括寰枢椎弓根螺钉、经寰枢侧块关节螺钉(Magerl技术)、枢椎椎板螺钉、下颈椎侧块螺钉及下颈椎棘突螺钉。58例“组合式固定”患者中,45例应用2种内固定方式组合,9例应用3种方式组合,4例应用4种方式组合。使用“组合式固定”的原因包括:枢椎段椎动脉高跨、枢椎椎弓根细小或椎体发育不良、颈椎椎弓根变薄(颈椎融合畸形患者)、枢椎椎弓根骨质疏松明显以及医源性枢椎椎弓骨折等。观察手术融合率及并发症,并比较手术前后的脊髓功能。结果:全部病例术中均未出现脊髓及血管损伤。随访时间24~72个月,平均36.8±10.5个月。57例(98.3%)未出现内固定松动或断裂并获得骨性融合,1例发生内固定松动造成未融合。术前合并颈脊髓功能损害者32例,术后脊髓功能均获得不同程度改善(术后JOA 11~17分,平均15.2±1.5分)。6例患者出现了并发症,包括伤口感染延迟愈合、脑脊液漏以及内固定松动。结论:针对合并颅椎区骨发育畸形、血管变异或者常规固定方式失败的寰枢椎不稳或脱位患者,合理选择“组合式”内固定治疗是安全、有效的。     

经后路寰椎椎弓根螺钉系统内固定融合术治疗上颈椎疾患

目的探讨经后路寰椎椎弓根螺钉系统内固定融合术治疗上颈椎疾患的可行性、方法、疗效和适应证。方法2004年10月～2006年1月,采用后路寰椎椎弓根螺钉系统内固定融合术治疗17例上颈椎疾患患者。男13例,女4例;年龄19～52岁。寰枢椎脱位14例,其中先天性齿状突不连3例,陈旧齿状突骨折4例,新鲜齿状突骨折（C型）2例,寰椎横韧带断裂3例,寰椎骨折2例;枢椎肿瘤2例;C2、3巨大神经鞘膜瘤1例。术前JOA评分8.3±3.0分。结果17例手术时间2.1～3.4h,平均2.7h;出血量300～750ml,平均490ml。术中未发生椎动脉和脊髓损伤。1枚寰椎椎弓根螺钉前端穿透侧块内上皮质约3mm,但未影响寰枕关节活动,余位置满意。患者全部获3～18个月定期随访。螺钉位置良好,无钉棒断裂、变形及松动,3～6个月后患者均获植骨融合。术后3个月JOA评分14.6±2.2分,恢复率73%～91%,平均82%。结论经后路寰椎椎弓根螺钉系统内固定融合术治疗上颈椎疾患具有可行性,若术中操作得当,其疗效较好,适应证较广。