A retrospective study of congenital osseous anomalies at the craniocervical junction treated by occipitocervical plate-rod systems

Purpose

To evaluate the effectiveness of posterior occipitocervical reconstruction using the anchors of cervical pedicle screws and plate-rod systems for patients with congenital osseous anomalies at the craniocervical junction.

Methods

Twenty patients with congenital osseous lesions who underwent posterior occipitocervical fusion using the anchors of cervical pedicle screws and plate-rod systems for reduction and fixation from 1996 to 2009 were reviewed. The lesions included os odontoideum, occipitalization of the atlas, congenital C2–3 fusion, congenital atlantoaxial subluxation, congenital basilar invagination and combined anomalies. The clinical assessment and the measurements of the images were performed preoperatively, postoperatively and at most recent follow-up.

Results

The combined deformity of flexion of the occipitoatlantoaxial complex and invagination of the odontoid process associated with congenital osseous lesions at the craniocervical junction was corrected by application of combined forces of extension and distraction between the occiput and the cervical pedicle screws. Preoperative myelopathy improved in 94.7 % patients. The mean Ranawat value, Redlund-Johnnell value, atlantodental distance, occiput (O)–C2 angle, and C2–C7 lordosis angle improved postoperatively and was sustained at most recent follow-up. The mean cervicomedullary angle improved from 129.3° preoperatively to 153.3° postoperatively. The mean range of motion at the lower adjacent motion segment remained unchanged at most recent follow-up. The fusion rate was 95 %.

Conclusions

The results of the present study indicate that posterior occipitocervical reconstruction using the anchors of cervical pedicle screws and plate-rod systems is an effective technique for treatment of deformities and/or instability caused by congenital osseous anomalies at the craniocervical junction.     

使用枢椎椎弓根螺钉和枕颈固定板的枕颈融合术

目的观察一种借助于枢椎椎弓根螺钉的枕颈固定装置治疗寰枢关节不稳定的效果。方法从2001年6月至2003年3月用自行设计的一套由椎弓根螺钉和枕颈固定板组成的枕颈固定器,治疗了38例寰枢关节不稳定的患者,其中24例有寰椎枕骨化。沿枢椎椎弓峡部的纵轴安置椎弓根螺钉,将枕颈固定板预弯后固定于枕骨,用螺母锁定固定板与椎弓根钉的过程中,利用固定板的曲度,使寰枢关节充分复位。植骨于枕骨与枢椎后弓间。结果36例获得了随访,平均18个月,均获得了骨性融合。没有神经、血管损伤和断钉、断板的病例。结论使用枢椎椎弓根螺钉和枕颈固定板的枕颈固定器不仅有可靠的、短节段固定作用,而且便于寰枢关节复位。     

枢椎棘突螺钉单侧应用联合对侧椎弓根螺钉固定的有限元分析

目的分析枢椎棘突螺钉单侧应用联合对侧椎弓根螺钉固定在寰枢和枕颈固定中的生物力学稳定性。方法构建正常枢椎解剖、椎板薄和椎动脉变异椎弓根细小3种不同解剖状态下的完整上部颈椎有限元模型作为完整模型组,然后分别模拟齿状突骨折进行寰枢固定和寰椎骨折进行枕颈固定。在寰枢固定中,比较单侧枢椎棘突螺钉+对侧椎弓根螺钉+双侧寰椎侧块螺钉固定组(棘突螺钉组)和枢椎双侧椎弓根螺钉+双侧寰椎侧块螺钉固定组(椎弓根螺钉组);在枕颈固定中,比较单侧枢椎棘突螺钉+对侧椎弓根螺钉+枕骨螺钉固定组(棘突螺钉组)和枢椎双侧椎弓根螺钉+枕骨螺钉固定组(椎弓根螺钉组)。枢椎棘突螺钉分别测试水平、斜向、垂直置钉3种不同的固定技术。模拟颈椎运动,测量枕颈的屈伸、侧屈、旋转的关节活动范围(ROM)。结果在寰枢和枕颈固定中,棘突螺钉组和椎弓根螺钉组的C1~C2屈伸、侧屈、旋转ROM均较完整模型组均明显下降。在寰枢固定中棘突螺钉组C0~C2屈伸、侧屈、旋转的ROM大于椎弓根螺钉组;在枕颈固定中,棘突螺钉组C1~C2侧屈的ROM大于椎弓根螺钉组,棘突螺钉组的C0~C2旋转的ROM大于椎弓根螺钉组。枢椎棘突螺钉分别测试水平、斜向、垂直固定间有差异,但不明显。结论在寰枢和枕颈固定中,枢椎双侧椎弓根螺钉固定和枢椎单侧棘突螺钉联合对侧椎弓根螺钉组合式固定方法均具有良好的稳定性。在寰枢固定中,相对于枢椎棘突螺钉组合式固定,枢椎双侧椎弓根螺钉固定具有更好的寰枢稳定性。在枕颈固定中,枢椎双侧椎弓根螺钉固定在侧屈和旋转活动上较枢椎棘突螺钉组合式固定稳定性更好。枢椎三种棘突螺钉置钉技术间的稳定性差异并不明显。     

Complications of pedicle screw fixation in reconstructive surgery of the cervical spine

STUDY DESIGN: Retrospective evaluation of complications in 180 consecutive patients with cervical disorders who had been treated by using pedicle screw fixation systems. OBJECTIVES: To determine the risks associated with pedicle screw fixation in the cervical spine and to emphasize the importance of preoperative planning and surgical techniques in reducing the risks of this procedure. SUMMARY OF BACKGROUND DATA: Generally, pedicle screw fixation in the cervical spine has been considered too risky for the neurovascular structures. There have been several reports describing the complications of lateral mass screw-plate fixation. However, no studies have examined in detail the complications associated with cervical pedicle screw fixation. METHODS: One hundred eighty patients who underwent cervical reconstructive surgery using cervical pedicle screw fixation were reviewed to clarify the complications associated with the pedicle screw fixation procedure. Cervical disorders were spinal injuries in 70 patients and nontraumatic lesions in 110 patients. Seven hundred twelve screws were inserted into the cervical pedicles, and the locations of 669 screws were radiologically evaluated. RESULTS: Injury of the vertebral artery occurred in one patient. The bleeding was stopped by bone wax, and no neurologic complication developed after surgery. On computed tomographic (CT) scan, 45 screws (6.7%) were found to penetrate the pedicle, and 2 of 45 screws caused radiculopathy. Besides these three neurovascular complications directly attributed to screw insertion, radiculopathy caused by iatrogenic foraminal stenosis from excessive reduction of the translational deformity was observed in one patient. CONCLUSIONS: The incidence of the clinically significant complications caused by pedicle screw insertion was low. Complications associated with cervical pedicle screw fixation can be minimized by sufficient preoperative imaging studies of the pedicles and strict control of screw insertion. Pedicle screw fixation is a useful procedure for reconstruction of the cervical spine in various kinds of disorders and can be performed safely.     

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.     

脊柱脊髓损伤的修复与重建进展

目的阐明脊柱脊髓损伤临床与基础的最新进展。方法通过广泛查阅文献，并结合自身的研究结果和临床经验，对近年来脊柱脊髓损伤的临床治疗和基础研究进行总结。结果上颈椎骨折脱位的治疗，以侧块螺钉和椎弓根钉为基础的枕颈融合和寰枢椎融合技术不仅固定牢靠，而且符合生物力学要求。下颈椎骨折脱位的治疗，包括颈前路钢板固定和颈后路侧块或椎弓根钉固定融合术，椎间盘性疾病可考虑人工颈椎间盘置换，则更加符合人体动态的生物力学要求。胸椎骨折手术治疗术式的选择目前仍有争议。近年来，腰椎的动力学固定和人工腰椎间盘置换己取得长足进步，降低了因腰椎融合术而导致的邻近节段病发病率，但缺少长期随访的临床资料。脊髓损伤机制方面的研究，特别是凋亡信号传导机制的研究，近年来取得了很大进展。脊髓损伤的治疗，特别是生物学的治疗，包括细胞移植和基因治疗，均为临床治疗提供了坚实的理论基础。结论随着医学发展和技术创新，脊柱脊髓损伤的修复与重建进展迅速。     

寰枢椎椎弓根螺钉内固定术治疗儿童寰枢椎脱位的初步报告

目的:探讨寰枢椎椎弓根螺钉内固定手术治疗儿童寰枢椎脱位的可操作性和近期疗效。方法:2005年9月~2011年3月对16例儿童寰枢椎脱位患者采用寰枢椎椎弓根螺钉内固定术治疗,男9例,女7例;年龄5～13岁,平均9.1岁。均有枕颈部疼痛、颈部僵硬;3例有高位颈脊髓病表现,ASIA分级:D级2例,C级1例。术前均行颈椎正侧位及过伸过屈位X线片、CT和MRI检查,均诊断为寰枢椎脱位,其中寰椎横韧带断裂1例,寰枢椎骨折脱位1例,先天性齿状突畸形12例,寰枢椎固定旋转半脱位2例;颈脊髓受压5例。寰椎后弓(椎弓根)高度2.5~3.8mm,平均3.0mm;寰齿前间隙6~14mm,平均9mm。术前常规行牵引1~2周复位,完全复位7例,部分复位5例,不能复位4例。术中采用"寰椎椎弓根显露置钉法",在直视下行C1、C2置钉,复位固定,植骨融合。随访患者症状和神经功能改善情况,定期行颈椎X线片及CT复查,了解内固定及植骨融合情况。结果:16例均行双侧寰枢椎椎弓根螺钉内固定,手术过程顺利,64枚螺钉均成功置入,复位固定满意,无术中、术后神经和血管并发症。术中出血150~650ml,平均300ml;手术时间100~190min,平均130min。12例随访12~72个月,平均28.5个月,术后3~6个月寰枢椎均骨性融合;末次随访时,颈枕症状明显改善,3例术前有脊髓功能损害者均好转,2例术前ASIA分级D级者恢复到E级,1例术前ASIA分级C级者恢复到D级;未发现螺钉松动、断钉和寰枢椎再移位现象,未发现曲轴现象。结论:采用"寰椎椎弓根显露置钉法"行寰椎椎弓根螺钉内固定可操作性强,置钉安全性高;寰枢椎椎弓根螺钉内固定治疗儿童寰枢椎脱位的近期疗效满意。     

Pedicle screw fixation in the cervical spine

Pedicle screw fixation of the lower cervical spine is a new technique that provides an alternative to posterior lateral mass plating. Although biomechanical studies support the use of pedicle screws to reconstruct the cervical spine, placing screws into the small cervical pedicle poses a technical challenge. Penetration of the pedicle is the primary complication associated with screw insertion in the lower cervical spine. Pedicle screw fixation at the C2 and C7 pedicles in conjunction with use of plates for occipitocervical or cervicothoracic plating is becoming an accepted technique; however, pedicle screw fixation should not be routinely used at the C3-C6 levels. It may be indicated in patients who have osteoporotic bone or when rigid internal fixation cannot be achieved by conventional techniques.     

三维平板透视引导上颈椎椎弓根螺钉置入准确性及疗效分析

目的 评价在三维平板透视系统引导下应用上颈椎椎弓根螺钉内固定加植骨融合技术治疗上颈椎骨折的安全性和临床疗效。方法 回顾性分析自2012-06-2013-10我科收治的11例上颈椎骨折脱位病例,均在术中三维平板透视系统引导下采用上颈椎椎弓根螺钉短节段内固定加植骨融合技术进行手术治疗。结果 术后所有患者的颈椎稳定性均得到即刻恢复,44枚螺钉均在位良好,未发生脊髓及椎动脉损伤等任何与置钉相关的并发症,无螺钉断裂、松动。结论 在三维平板透视系统引导下经上颈椎椎弓根螺钉内固定加植骨融合技术治疗上颈椎骨折脱位,螺钉置入准确性高,有效防止置钉并发症,力学稳定性好,植骨融合率高,是上颈椎骨折后路固定术中理想的手术方式之一。     

Clinical application of C2 laminar screw technique

C2 laminar screws have become an increasingly used alternative method to C2 pedicle screw fixation. However, the outcome of this technique has not been thoroughly investigated. A total of 35 cases with upper cervical spinal instability undergoing C2 laminar screw fixation were reviewed. All cases had symptoms of atlantoaxial instability, such as craniocervical junction pain, and were fixed with the Vertex cervical internal fixation system. A total of 68 screws were placed and hybrid constructs (a C2 translaminar screw combined with a C2 pars screw) were incorporated in two patients. In this series, there were no intraoperative complications and no cases of neurological worsening or vascular injury from hardware placement. Computed tomographic scans demonstrated a partial dorsal laminar breach in ten patients. None of these resulted in neurological symptoms. None of the patients was found to have a breach of the ventral laminar cortex. All the C2 laminar screws fixations were performed successfully. There was no instability seen on the films with no evidence of hardware failure or screw loosening during the follow-up period in all patients. In conclusion, C2 laminar screw technique is straightforward and easily adopted; it can efficiently and reliably restore upper cervical stability. It is an alternative method to C2 pedicle screw fixation, especially in patients with unilateral occlusion of vertebral artery and pedicle deformity of C2.     

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 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.     

成人新鲜齿突骨折的手术治疗策略

目的总结应用前路齿突拉力螺钉或后路寰枢椎植骨融合技术治疗成人新鲜齿突骨折的疗效。方法回顾性分析2009年1月-2012年1月期间收治的46例成人齿突骨折患者,男29例,女17例;年龄19-68岁,平均40.5岁。患者均有不同程度的枕颈部疼痛和活动受限,其中7例患者伴有神经功能障碍,术前日本骨科学会（Japanese Orthopaedic Association,JOA）评分9-14分,平均12.7分。根据Anderson-D’Alonzo分型,Ⅱ型骨折33例（71.7%）,Ⅲ型骨折13例（28.3%）。8例患者有不同程度寰椎前脱位,术前寰齿间距（atlanto-dens interval,ADI）3-7 mm,平均4.3 mm,术前进行颅骨牵引术,均可复位。采用前路齿突拉力螺钉或后路寰枢椎植骨融合术治疗,随访患者临床症状和神经功能改善情况,影像学观察寰枢椎复位和植骨融合情况。结果患者均顺利完成手术,术中均未发生椎动脉和脊髓损伤。共置入25枚齿突螺钉和84枚寰枢椎椎弓根螺钉,术后X线片及三维CT检查显示25枚齿突螺钉位置均较好,3枚寰椎椎弓根螺钉内倾角不够,螺钉部分穿破椎动脉孔内侧壁,椎动脉造影未见椎动脉损伤;1枚寰椎椎弓根螺钉内倾角过大,螺钉部分穿破椎管内侧壁,未出现新的神经损伤症状;其余螺钉位置满意。术后ADI为1-2.5 mm,平均1.6 mm。患者均获随访,随访时间8-36个月,平均23个月,术后6个月随访时神经功能明显改善,JOA评分为14-17分,平均16.2分,平均改善率为89.3%。1例行前路齿突螺钉内固定术的患者齿突骨折端硬化,有明显的骨不连发生,其余患者均在术后6个月获得骨性融合,融合率为97.8%;随访期间未发现螺钉松动、移位、螺钉断裂和寰枢椎再移位、失稳现象。结论选择前路齿突拉力螺钉或后路寰枢椎植骨融合技术治疗成人新鲜齿突骨折,可获得良好的临床效果。     

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.     

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.     

陈旧性寰枢椎脱位与枕颈不稳的手术治疗

目的　观察两种内固定方法治疗陈旧性寰枢椎脱位与不稳的疗效。方法　自 1992—2 0 0 0年收治 36例陈旧性寰枢椎脱位与枕颈不稳的患者 ,年龄 12～ 6 1岁 ,平均 38岁 ;病程 1个月～ 8年 ,平均 16个月。 2 2例颅骨牵引复位或基本复位的 ,用 Gallie法寰枢椎固定 ,C1～ 2 髂骨植骨。 9例牵引未复位和 5例枕颈区畸形的 ,用 Ransford环固定 ,枕颈区减压 (C0 ～ C2 )和枕颈植骨融合。结果　 1例术后 4天死亡 ,35例随访 3个月～ 4年。寰枢椎固定 2 2例中 2 1例获骨性融合 ,2例复位不满意 ,其中 1例植骨不愈合。Ransford法 13例有 12例骨性融合 ,1例植骨块断裂未愈合 ,但内固定无松动。术后神经功能明显改善。结论　颅骨牵引复位的陈旧性寰枢椎脱位 ,Gallie法寰枢椎固定疗满意。 Ransford环固定对枕颈区减压和枕颈融合能提供可靠的固定作用。     

颅脊交界疾患经口手术的枕寰枢置钉策略

目的:探讨颅脊交界疾患经口手术枕寰枢螺钉固定的置钉策略.方法:2010年1月～2010年12月,30例颅脊交界疾患病例(包括寰枢椎脱位12例,颅底凹陷症15例和先天性颅脊交界畸形3例)均采用第三代经口寰枢椎复位钢板(transoral atlantoaxial reduction plate-Ⅲ,TARP-Ⅲ)内固定植骨融合手术进行治疗.患者术前均有颈部不适和不同程度的肢体麻木、无力等高位脊髓受压表现,影像学检查均存在脊髓腹侧受压.按美国脊髓损伤协会(American Spinal Injury Association,ASIA)分级:C级5例,D级25例.ASIA运动评分为42～96分,平均77.2±14.4分.所有病例均通过计算机辅助设计快速成型(computer aided design and rapid prototype,CAD-RP)技术制作颅脊交界区的1∶1三维模型实物,13例复杂病例术前在模型实物上模拟手术进钉.枕寰枢螺钉的选择主要采用四种方法:A,C0/C1融合者(存在先天性寰椎枕骨化畸形的患者)采用寰椎侧块枕骨髁融合体螺钉;B,C0/C1未融合者(C1侧块完整的患者)采用寰椎侧块螺钉;C,无颅底凹陷且枢椎椎弓根发育正常的患者采用枢椎经口逆向椎弓根螺钉;D,存在颅底凹陷或虽无颅底凹陷但枢椎椎弓根发育狭小或存在椎动脉高跨等无法置入椎弓根螺钉的患者,采用枢椎经口逆向关节突螺钉.本组颅底凹陷症患者TARP-Ⅲ内固定时采用AC或AD的螺钉组合,寰枢椎脱位和先天性颅脊交界畸形患者采用BC或BD的螺钉组合,从而形成TARP固定的4种螺钉组合方式:AC、AD、BC或BD.随访观察治疗效果.结果:30例患者术后颈部局部症状和肢体麻木无力症状均不同程度改善,无感染、神经血管损伤、钉板松脱等并发症发生,2例术后有短暂头晕,术后2周～1个月自愈.术后影像学检查内固定位置满意,脊髓压迫均彻底解除.术后25例ASIA分级D级患者中的8例改善至E级,其余17例分级无变化,但术后运动评分改善至87～100分(96.4±4.2分);5例C级患者均改善至D级.术后随访3～12个月,平均7.2个月,所有病例均获骨性融合,30例计120枚螺钉(包括寰椎侧块枕骨髁融合体螺钉30枚,寰椎侧块螺钉30枚,枢椎经口逆向椎弓根螺钉16枚和枢椎经口逆向关节突螺钉44枚)均位置理想.结论:不同的颅脊交界疾患病例行经口入路手术时,应选择不同的螺钉固定方法,通过枕寰枢螺钉的多种组合方式,可达到使TARP坚强固定寰枢关节的作用.     

寰枢椎脱位后路螺钉固定方法的临床选择

目的 探讨寰枢椎脱位后路钉棒固定术中寰椎螺钉和枢椎螺钉固定方法 的临床选择.方法 对2002 年11 月至2011 年12 月广州军区广州总医院收治的228 例可复性和23 例难复性寰枢椎脱位患者,术前进行置钉可行性和复位可能性评估,针对性地选择寰椎和枢椎的后路螺钉固定方法,进行寰枢椎后路钉棒固定治疗.结果 251 例患者均行钉棒固定并获得满意复位.寰椎螺钉固定采用椎弓根螺钉403 枚、部分经椎弓根螺钉77 枚、侧块螺钉22 枚;枢椎螺钉固定采用椎弓根螺钉437 枚、椎板螺钉56 枚、侧块螺钉9 枚.术中未发生椎动脉、脊髓损伤.237 例患者获得随访,随访时间4～38 个月,平均随访时间13 个月.230 例患者获骨性融合;6例为纤维愈合,动力位片（均随访2 年以上）未见复发脱位;另1 例为假关节未融合并双侧枢椎椎弓根螺钉松动,行后路翻修手术治愈.结论 根据寰枢椎脱位的复位难易程度和个体解剖特点灵活选择寰椎和枢椎不同的后路螺钉固定方法,扩大了寰枢椎后路钉棒固定技术的适用范围,提高了手术安全性和成功率.     

Freehand C1 lateral mass screw fixation technique: our experience

Background

Although C1 lateral mass fixation technique is frequently performed in upper cervical instabilities, it requires the guidance of fluoroscopic imaging. The fluoroscopy guidance is time-consuming and has the risks of accumulative radiation. Biplane fluoroscopy is also difficult in upper cervical pathologic conditions because of the use of cranial fixations. This study aimed to demonstrate that unicortical C1 lateral mass screws could be placed safely and rapidly without fluoroscopy guidance.

Methods

Between 2002 and 2008, 32 C1 lateral mass screws were inserted in 17 consecutive patients with various pathologic conditions involving either atlantoaxial or occipitocervical instability.

Results

C1 screw lengths ranged from 18 to 32 mm. The atlantoaxial fixation was performed in 13 patients, and C1 lateral mass screws were added to the occipitocervical construct in 3 patients, to the posterior cervical construct in 2 patients, and to the cervicothoracic construct in 1 patient. In 2 patients, because C1 lateral mass screws could not be inserted unilaterally, C1 pedicle screw analogs were inserted. There were no screw malpositions or neurovascular complications related to screw insertion. Operation time and intraoperative bleeding of the isolated atlantoaxial fixations were retrospectively evaluated. The mean follow-up was 32.3 months (range, 7-59 months). No screw loosening or construct failure was observed within this period. Postoperatively, 4 patients complained of hypoesthesia, whereas one patient had superficial wound infection.

Conclusion

C1 lateral mass screws may be used safely and rapidly in upper cervical instabilities without intraoperative fluoroscopy guidance and the use of the spinal navigation systems. Preoperative planning and determining the ideal screw insertion point, the ideal trajections, and the lengths of the screws are the most important points.     

后路寰枢椎椎弓根螺钉结合单侧枢椎棘突椎板钉固定治疗寰枢椎不稳的临床疗效

 目的探讨后路寰枢椎椎弓根螺钉结合单侧枢椎棘突椎板钉加同种异体骨植骨融合术治疗寰枢椎不稳的临床疗效。方法回顾性分析2010年3月至2014年4月,采用枢椎棘突椎板钉结合寰枢椎椎弓根固定植骨融合术治疗10例寰枢椎不稳定患者资料,男6例,女4例;年龄16~62岁,平均39岁;单侧椎动脉高跨畸形伴寰枢椎不稳定7例,枢椎单侧关节突破坏累及椎弓根致寰枢椎不稳定3例。患者均表现为颈部活动受限及疼痛,VAS评分1~8分,平均（3.70±2.11）分,其中3例伴肌力下降及感觉异常。术前常规行影像学检查,术后7 d及1、3、6、12个月行X线和CT检查,了解内固定位置及植骨融合情况;比较手术前后VAS评分。结果10例患者均获得随访,随访时间9~18个月,平均13个月。术中无一例发生颈脊髓和椎动脉损伤,除1例颈部肌肉肥厚者需另开软组织通道置入螺钉外,其余均一次性置钉成功。1例术后第3天切口出现渗液,考虑为同种异体骨排异反应,对症换药后5天停止渗液,余切口均一期愈合。术后VAS评分（1.01±0.89）分,较术前明显减轻。术后X线片示颈椎序列恢复良好,CT示1例患者寰椎椎弓根钉道内侧皮质破损,椎管未侵犯,余螺钉位置正常;术后6个月X线片及CT检查均见骨性融合。结论寰枢椎椎弓根螺钉结合单侧枢椎棘突椎板钉植骨融合术治疗寰枢椎不稳,近期疗效肯定。