Os Odontoideum: A Cause of Atlanto-Axial Instability

Os odontoideum is a rare condition in which instability may damage the upper cervical cord. A delay in diagnosis is not uncommon. This paper describes a series of 11 patients with os odontoideum. The presenting symptoms were divided into three groups: posttraumatic neck-pain, gradually appearing signs of medullary compression and an asymptomatic group. Eight patients had atlanto-axial instability. Six had interlaminar fusion between atlas and axis. No serious complications were seen. Stability was obtained in all patients postoperatively. In case of significant instability, fusion is indicated. In patients with cerebral palsy a closer examination of the upper cervical cord is recommended.     

Varied clinical presentation of os odontoideum: a case report

Objective:

To present a case of an os odontoideum and to provide insight into the varied clinical presentations.

Clinical Features:

A 54 year old man presented with chronic neck pain without headache. A clinical examination was performed and the chiropractor viewed his AP and lateral radiographs. Previous flexion/ extension radiographs and MRI imaging from 2009 were requested for review. The patient was diagnosed with grade II mechanical neck pain. Treatment was rendered that day which included spinal manipulation/ mobilization. Several days later the requested imaging reports were received and described the presence of an os odontoideum.

Conclusion:

In the presence of os odontoideum, familiarity with the signs and symptoms of potential cervical instability is imperative. Health care providers must remain diligent in their patient histories, physical exams, and imaging. This case highlights the importance of following up on imaging studies to rule out diagnoses that would involve treatment contraindications thus ensuring safe and effective treatment.     

术中即时三维导航辅助下后路内固定治疗症状型游离齿突

背景：上颈椎解剖变异较大且有重要的神经血管毗邻,对症状型游离齿突患者的手术治疗提出了挑战,目前有多种治疗方法,但各有局限。目的：评估术中即时三维导航辅助下行后路螺钉固定治疗症状型游离齿突患者的准确性和临床效果。方法：34例症状型游离齿突患者均在术中即时三维导航辅助下行后路内固定手术,采用寰枢椎经关节螺钉固定术21例,寰枢椎多轴螺钉固定术12例,另1例患者左侧为多轴螺钉固定右侧为经关节螺钉固定。颈部疼痛采用视觉模拟疼痛评分（VAS）,神经功能评价采用JOA评分,患者满意度采用Odom评分。将螺钉位置分为3级：Ⅰ级为理想置钉,螺钉完全位于骨皮质内;Ⅱ级为可接受置钉,螺钉穿出周围骨皮质但穿出部分小于螺钉直径的1/2;Ⅲ级为不可接受置钉,明显侵犯横突孔或是椎管。结果：全部患者获得随访,随访时间为6~65个月,平均25.7个月。34例患者共置入经关节螺钉43枚,多轴螺钉50枚。其中3枚多轴螺钉和4枚经关节螺钉轻度穿破单侧横突孔,但术中无椎动脉和脊髓损伤表现。患者的术前JOA评分为5~14分,平均8.3分,提高至末次随访的8~17分,平均12.4分,改善率为47.1%。术前VAS为3~7分,平均4.1分,降低至术后3个月随访的0~4分,平均0.7分,改善率为83.7%。末次随访的Odom评分：优为47%,良为38%,可为12%,差为3%。所有病例均获得复位和骨性融合,未出现内固定失效的并发症。结论：对于症状型游离齿突患者,术中即时三维导航辅助下后路螺钉内固定是一种安全、准确和有效的治疗方法。     

Interlaminar Atlanto-Axial Fusion for Instability

At the Departments of Neurosurgery and Orthopaedic Surgery in Odense 36 patients were treated with atlanto-axial interlaminar fusion. The operation was performed jointly by the neurosurgeon and orthopaedic surgeon, working as a team, using a specially developed technique. Two bone grafts from the iliac crest were shaped, with grooves for the two laminae, and fixed with wire on the right and left side. Postoperative immobilization in a Minerva jacket was maintained for 3 months and a plastic collar was worn for another 3 months.

Twenty-one patients had odontoid fractures, five of them with pseudarthrosis. Ten had atlanto-axial instability caused by rheumatoid arthritis. The instability was horizontal in seven cases, with a mean distance of 12 mm from the odontoid process to the anterior arch of the atlas. Five patients had vertical dislocation with the apex of the odontoid process protruding 8 mm (mean) cranially to the foramen magnum, and eight had cord signs. Two patients had an os odontoideum with instability after trauma, and three had other lesions.

At follow-up, at least 1 year after the operation, all fusions were solid, and all fractures but one had healed. The rheumatoid patients had achieved great relief of symptoms with minimum restriction of movement in the cervical spine. The indications for operation on patients with rheumatoid arthritis are very restrictive.     

Interlaminar Atlanto-Axial Fusion for Instability

At the Departments of Neurosurgery and Orthopaedic Surgery in Odense 36 patients were treated with atlanto-axial interlaminar fusion. The operation was performed jointly by the neurosurgeon and orthopaedic surgeon, working as a team, using a specially developed technique. Two bone grafts from the iliac crest were shaped, with grooves for the two laminae, and fixed with wire on the right and left side. Postoperative immobilization in a Minerva jacket was maintained for 3 months and a plastic collar was worn for another 3 months.

Twenty-one patients had odontoid fractures, five of them with pseudarthrosis. Ten had atlanto-axial instability caused by rheumatoid arthritis. The instability was horizontal in seven cases, with a mean distance of 12 mm from the odontoid process to the anterior arch of the atlas. Five patients had vertical dislocation with the apex of the odontoid process protruding 8 mm (mean) cranially to the foramen magnum, and eight had cord signs. Two patients had an os odontoideum with instability after trauma, and three had other lesions.

At follow-up, at least 1 year after the operation, all fusions were solid, and all fractures but one had healed. The rheumatoid patients had achieved great relief of symptoms with minimum restriction of movement in the cervical spine. The indications for operation on patients with rheumatoid arthritis are very restrictive.     

先天性颈椎融合伴颈椎间盘突出症12例报告

本文报告１２例先天性颈椎融合伴颈椎间盘突出症，探讨了其发生机理，诊断和治疗方法。指出此种类型颈椎间盘突出与先天性颈椎融合有密切关系。当存在先天性颈椎融合时，未融合的节段活动增加，使椎间盘较早和较容易发生退行性改变而引起颈椎间盘突出症。ＭＲＩ对其明确诊断具有重要价值。本病以采用手术疗法为主，其中以颈前路减压术为首选。     

Os odontoideum with ��free-floating�� atlantal arch causing C1-2 anterolisthesis and retrolisthesis with cervicomedullary compression

Background:

Os odontoideum (OO) with C1-2 anterolisthesis and retrolisthesis may cause cervicomedullary injury both from anterior and posterior aspects. We analyzed fourteen such patients for biomechanical issues, radiological features and management of OO with free-floating atlantal arch and review pertinent literature.

Materials and Methods:

Fourteen patients having nonsyndromic, reducible atlantoaxial dislocation (AAD) with orthotopic OO were analyzed. During neck flexion, their C1 anterior arch-os complex displaced anteriorly relative to remnant odontoid-C2 body. The posteriorly directed hypoplastic remnant odontoid sliding below the atlas and forward translation of the C1 posterior arch caused concomitant cervicomedullary compression. During neck extension, there was retrolisthesis of the “free-floating” C1 arch-os complex into spinal canal. Spinal stenosis and lateral C1-2 facet dislocation; Klippel-Feil anomaly; and posterior circulation infarcts were also present in one patient each, respectively. Posterior C1-2 (n=10) or occipitocervical fusion (n=3) was performed in neutral position to stabilize atlantoaxial movements.

Results:

Follow-up (mean, 3.9 years) assessment revealed improvement in spasticity and weakness in 13 patients. One patient had neurological deterioration following C1-2 posterior sublaminar fusion, requiring its conversion to occipitocervical contoured rod fusion. One patient with posterior circulation stroke died prior to any operative intervention. Follow-up lateral view radiographs showed a bony union or a stable construct in these 13 patients.

Conclusions:

OO with free-floating atlantal arch may precipitate cord injury both during neck flexion and extension. This condition may be overlooked unless lateral radiographs of craniovertebral junction are undertaken in neck extension, along with the usual ones in neutral and flexed positions. Etiological factors include C1 ring-OO unrestrained movements above the hypoplastic odontoid; upward pull on OO by alar and apical ligaments; lax C1-2 facet joint ligaments; and congenital presence of horizontal facet joint surfaces that facilitates C1-2 translation.     

先天性宫颈闭锁的诊疗策略分析

目的：探讨先天性宫颈闭锁的术前评估、手术方案的选择及对术后的影响。方法：对2005至2008年收治的12例先天性宫颈闭锁患者的临床资料进行分析和评估,以探讨该疾病最佳的治疗方法。结果：12例患者的年龄13～19岁,12例合并阴道闭锁,其中有4例合并子宫畸形,4例合并卵巢宫内膜囊肿。对5例患者行宫颈整形及阴道成形术,4例行子宫切除术,3例行子宫内膜切除术。结论：先天性宫颈闭锁的患者术前应尽早诊断,根据子宫内膜发育情况,仔细评估手术成功率及预后,选择个性化治疗方案,恢复生育功能,减少再手术的风险,术后应定期随访是手术后成功的重要环节。     

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。     

异体骨椎间融合器在颈椎前路融合术中的应用价值

目的探讨螺纹异体骨椎间融合支架(allograft interbody fusion cage,AIFC)在颈椎前融合术中的应用价值.方法自1998年6月～2000年6月,采用AIFC行颈椎前路融合术90例,其中男35例,女55例,年龄37～72岁,平均47岁,其中神经根型颈椎病56例,脊髓型颈椎病32例,椎动脉型颈椎病2例.采用颈前横行切口,C臂X线透视定位病变间隙,行环钻前路减压,AIFC植入融合固定.术后随访观察AIFC的融合率,椎间高度维持情况及有无并发症.结果76例获得良好随访,随访时间18个月～3年,平均26个月,术后3 d、1、3、6、9、12、18、24个月常规X线片检查,74例获得骨性融合,融合率为97.3%,椎间高度维持良好,AIFC无移位,2例成角畸形愈合,颈椎呈后凸畸形.结论AIFC具有良好的维持椎间高度功能,抗压缩、抗旋转,稳定性好,椎间融合率高,符合颈椎生物力学及临床要求.     

Plate and screw fixation for atlanto-axial subluxation

Summary Our experience with 30 cases of atlanto-axial dislocation, over the period of 3 years and 9 months, is described. A modified plate and screw method of fixation of the lateral masses of the atlas and axis was successfully used in these cases. The technical aspects and merits of the method, wherein a 100% union rate was achieved, with no morbidity, mortality, or instrument fatigue or failure, are presented. The average follow-up period is of 19 months. The technique provided immediate rigid segmental internal fixation, permitting early mobilization with minimal external support. Onlay and interfacetal bone grafts subsequently produced bony fusion. Direct application of screws to the atlas and axis, thus utilizing the firm purchase in their thick and large cortico-cancellous lateral mass, provides a biomechanically strong fixation of the region.Occipito-cervical fusion can be achieved in selected cases by a modification of the method. It appears that such a method of fixation could be useful at least in some complex congenital or traumatic craniovertebral region instability where the conventional methods have failed or are not suitable.     

梨状腹综合征1例报告并文献复习

目的探讨梨状腹综合征的临床特征及诊治方法,提高对梨状腹综合征的认识。方法回顾性分析1例梨状腹综合征的临床资料并复习有关文献。结果经导尿及抗感染治疗,患者症状缓解。随访6月,无复发。结论影像学检查可诊断此病。梨状腹综合征的发生可能与遗传因素有关。     

胸椎小关节紊乱症376例临床分析

在高原地区，人体受特殊环境气候条件的影响，胸椎小关节(包括胸椎上下关节突构成的胸椎后关节，肋骨小头与椎骨构成的肋骨小头关节和肋横突关节，下同)紊乱症发病率较高。过去，对颈、腰椎小关节紊乱症研究得多，对胸椎小关节紊乱症研究较少。以往人们认为胸椎属于较稳定且活动小的关节，受损机会较颈、腰椎少。因此，对本病的认识和重视程度不够，临床研究和报道甚少。     

青少年Chiari畸形伴胸椎侧凸远端融合范围的选择及疗效比较

目的 探讨青少年Chiari畸形伴胸椎侧凸不同远端固定节段的选择对手术疗效的影响.方法 后路选择性胸椎融合术且随访超过2年的青少年共27例,男11例,女16例;年龄为12～18岁,平均15.2岁.记录术前、术后以及末次随访时的临床资料及影像学指标:冠状面侧凸Cobb角、侧凸柔韧性、顶椎偏移(apical vertebral translation,AVT)、顶椎旋转(apical vertebral rotation,AVR)及躯干偏移;矢状面胸椎后凸角(thoracic kyphosis,TK)、胸腰段Cobb角(thoracolumbar kyphosis,TLK)、腰椎前凸角(lumbar lordosis,LL)及躯干偏移(sagittal vertical axis,SVA),并进行统计学分析.结果 随访时间2～7年,平均3.4年.末次随访时的胸弯矫正率为55.9％,矫正丢失率2.3％,腰弯自发矫正率为59.2％.术前腰弯修正为A型与B型两组患者末次随访时各项影像学指标的差异均无统计学意义.除腰弯修正为B型且远端固定椎为L1的病例末次随访时的平均LL(59.8°)明显大于L2者(40.8°)外,A型及B型病例中远端固定椎位于L1或L2者其他各项影像学指标的差异均无统计学意义.结论 术前腰弯修正为A型及B型的青少年Chiari畸形伴胸椎侧凸患者采用后路选择性胸椎融合术治疗,可获得满意的胸弯矫正及腰弯的自发性矫正.     

Successful treatment of an adult patient with pulmonary abscess secondary to congenital cystic adenomatoid malformation

We report a case of a 29 year old male who at age 25, developed a pulmonary abscess in the left lower lobe. A left lower lobectomy was performed following two recurrences on antibiotic treatment. The result of histopathological examination confirmed congenital cystic adenomatoid malformation (CCAM), a congenital disease characterized by multiple cysts resulting from adenomatous hyperplasia of the bronchial epithelia. In many cases, respiratory distress occurs during the neonatal period, and in about 80–85% of patients, CCAM is diagnosed before the age of two years due to respiratory infection. CCAM which was diagnosed in adulthood is very rare.     

脊髓型颈椎病与发育性颈椎管狭窄38例

目的 探讨发育性颈椎管狭窄与脊髓型颈椎病的发病关系及其临床意义。方法 100例确诊为脊髓型颈椎病的患者，经复查原始X线颈椎侧位片，并按照颈椎管矢状中径与颈椎体矢状中径比值法进行重新测量。其中手术患者24例，前路手术8例，后路手术16例。结果 100例脊髓型颈椎病患者有38例存在不同程度的发育性颈椎管狭窄。前路手术随访3例中，有2例加重，再行后路手术后明显改善，后路手术随访6例中，有4例完全恢复，1例因前方巨大间盘突出并骨化，再行前路手术后明显改善。另1例术后部分改善。结论 颈椎管发育性狭窄是脊髓型颈椎病发病的决定性因素之一，正确认识可以对手术方式的选择及其预后有重要的指导意义。     

颈椎管内巨大巨长型神经鞘瘤的治疗体会

目的总结巨大巨长型椎管内神经鞘瘤的临床特点及治疗体会。方法回顾分析8例巨大巨长型椎管内神经鞘瘤患者的临床资料。结果 6例肿瘤全切除,2例因瘤体巨大未能全切。术后患者局部疼痛和麻木症状得到明显缓解。结论手术是治疗该肿瘤唯一有效的方法,术中充分显露,整体切除,注意预防颈髓损伤及重建脊柱稳定性是其操作关键。     

经椎弓根截骨术治疗胸腰椎后凸畸形

目的评估经椎弓根截骨术矫正胸腰椎后凸畸形的临床疗效和安全性。方法2001年3月~2007年4月,15例胸腰椎后凸畸形患者进行经椎弓根截骨矫形术。其中强直性脊柱炎8例,陈旧性胸腰椎骨折7例。对所有患者进行随访,内容包括矫正情况、腰痛和Oswestry功能评分的变化。结果平均随访时间为25个月。平均手术时间为230min,术中平均出血量为1780ml。术前后凸Cobb角平均为47.2°,术后为18.0°,平均矫正角度32.3°,融合率80%。术前患者腰痛VAS评分平均为7.4分,术后3.7分。术前ODI平均为58.9%,术后为30.0%。患者主观满意率93.3%。无术中和术后并发症。结论经椎弓根截骨术对于矫正胸腰椎后凸畸形有效而安全,应该根据患者的实际情况选择合适的截骨部位。     

前方经咽后入路切口治疗上颈椎病变

目的探讨颈椎前方经咽后入路切口治疗上颈椎病变的临床疗效。方法 9例上颈椎病变患者,均采用前方经咽后入路切口实施颈椎前路手术,其中包括前后路手术1例,术前JOA评分平均（8.6±1.2）分,枢椎椎弓骨折2例,颈椎肿瘤3例,颈椎结核1例,颈椎间盘突出2例,颈椎畸形1例。结果 9例患者术中均清楚显露C1~C3椎体前方,完成减压复位、病灶清除、融合内固定等操作;有脊髓压迫者术后脊髓神经功能得到一定程度的改善。全部伤口于2周后获甲级愈合,无伤口感染病例。1例术后出现口轮匝肌瘫痪,1周左右自行缓解,1例出现术后呛咳,3周左右自行缓解,其余病例未出现颈部重要神经血管损伤与相应节段的颈髓损伤。9例患者均经平均12（10~16）个月随访,JOA评分术后平均（13.4±1.6）分,与术前比较有显著差异（P〈0.01）。结论经高位前方咽后入路可充分显露上颈椎前方,进行直接有效的手术操作,创伤小,并发症少,是理想的显露途径。