Unstable os odontoideum in young children

Os odontoideum is a rare anomaly of the odontoid process. When unstable, it can be a source of neck pain that can result in serious neurological injury. In young children, the presence of a transverse lucency at the base of the dens represents the normal developing growth plate. However, os odontoideum should be considered in the differential diagnosis in a child with recurrent or persistent neck pain. A case of an unstable os odontoideum in a two-year-old child is presented to illustrate this point.     

后路融合术治疗齿状突游离小骨并寰枢椎不稳

目的通过临床病例回顾,分析后路融合内固定术治疗齿状突游离小骨合并寰枢椎不稳的临床特点及疗效,为临床诊疗提供参考。方法 2006年10月至2008年12月,采用后路寰枢椎融合或枕颈融合术治疗合并寰枢椎不稳的齿状突游离小骨57例,男34例,女23例。年龄13～71岁,平均37.4岁。有明确外伤病史者41例。55例存在不同程度的脊髓压迫症状。术前ASIA（American Spinal Injury Association）脊髓神经功能分级：B级3例,C级33例,D级19例,E级2例。结果随访时间6～60个月,平均26个月。51例获得骨性融合,6例发生延迟愈合。无因手术操作致椎动脉和脊髓损伤病例。无内固定脱落、断裂、退钉等并发症。所有病例枕颈部症状消失,术后ASIA脊髓神经功能分级：C级5例,D级35例,E级17例。结论术前认真分析,选择合适的后路融合术式能有效治疗齿状突游离小骨合并寰枢椎不稳,减少手术并发症。     

正常儿童齿状突影像学测量

目的测量不同年龄儿童正常齿状突的参数,确立不同年龄儿童正常齿状突的各种参数变化,为儿童齿状突中空拉力螺钉内固定提供参数依据。方法利用CT二维重建技术,测量120例不同年龄组儿童正常齿状突基底横断面松质骨、皮质骨的横径、纵径,模拟入钉点（C2椎体前下缘中点）至齿状突尖部前角、后角的角度及距离,最佳角度及最佳长度。结果正常儿童齿状突基底部基本呈圆形,纵径稍大于横径,各参数随年龄增大而增大。入钉的安全角度范围：16°～36°,最佳入钉角度范围：19°～22°。3～5岁、6～9岁和10～14岁3组的钉道长度安全范围分别为8～14mm、10～16mm、12～21mm;最佳长度分别为13～14mm、15～16mm、19～20mm。枢椎高度随年龄增加而逐渐增大。结论对于Ⅱ型齿状突骨折儿童进行齿状突螺钉固定时,可根据不同年龄齿状突的不同参数变化,选择相应的螺钉直径、长度和进钉方向。     

关节间隙螺钉加寰椎挂钩治疗齿状突游离小骨

目的评价C1～C2关节间隙螺钉加寰椎椎板钩治疗齿状突游离小骨合并寰枢椎不稳的临床特点及疗效。方法2004年10月至2007年2月,采用C1～C2关节间隙螺钉及寰椎椎板钩治疗合并寰枢椎不稳的齿状突游离小骨18例,男7例,女11例。年龄13-69岁,平均35．2岁。其中,有明确外伤病史11例。所有病例均存在枕颈部症状,15例存在不同程度的脊髓压迫症状。术前ASIA脊髓神经功能分级：B级2例;C级7例：D级6例;E级3例。术后定期随访,并对临床症状及影像学表现进行分析。结果随访时间6～58个月,平均21个月。术后3月所有病例枕颈部症状消失,X线及CT重建提示所有病例均获得良好骨性融合,寰枢椎序列良好,ASIA脊髓神经功能分级：C级4例,D级7例,E级7例。无因手术操作致椎动脉和脊髓损伤病例。无内固定脱落、断裂、退钉、假关节形成或寰枢椎不稳等并发症。结论C1～C2关节间隙螺钉加寰椎椎板钩是治疗齿状突游离小骨合并寰枢椎不稳的有效方法。     

儿童齿状突游离小骨继发寰枢关节脱位的术式选择及疗效观察

目的 :探讨儿童齿状突游离小骨继发寰枢关节脱位的手术方式,并观察其临床疗效。方法 :2009年1月~2014年1月收治12例儿童齿状突游离小骨继发寰枢椎脱位患者,其中7例可复性脱位患者行后路寰枢椎融合术,4例难复性脱位或复位后脊髓前方存在压迫的患者行前路经口咽减压联合后路寰枢椎融合术,1例难复性脱位患者行前路经口咽减压联合后路枕颈融合术,术后1、3、6、12个月及末次随访时评估患者临床表现及影像学改变。结果:所有患者均获得随访,随访时间28±15个月(12~60个月);术后患者临床症状均得到明显改善,11例短节段融合固定患者颈部屈伸活动功能良好,轴向旋转稍受限;1例患者术后8个月出现内固定断裂及寰枢椎脱位,行后路翻修手术后6个月植骨融合,其余患者均在术后6.0±2.5个月(3~12个月)植骨融合。末次随访时,患者JOA评分由术前的9.6±1.4分提高到16.2±0.7分。结论:后路植骨融合内固定术是治疗儿童齿状突游离小骨继发寰枢关节脱位安全有效的方法,对于难复性脱位患者或复位后存在软组织对脊髓构成持久压迫的患者需联合前路经口咽减压。     

Os odontoideum with posterior atlantoaxial instability

Nine patients who had os odontoideum with posterior atlantoaxial instability are reviewed. Three parameters were measured on the lateral radiographs: the distance from the os odontoideum to the spinous process of the axis in extension (Dext), the distance from the os odontoideum to the posterior arch of the atlas (Datl), and the degree of instability (Inst). Patients were classified into four groups: Group I, local symptoms (N = 3); Group II, transient myelopathy (N = 0); Group III, progressive myelopathy (N = 6); and Group IV, cerebral symptoms (N = 0). The development of cervical myelopathy was not related to degree of instability but to distance from the os to the spinous process of the axis (Dext). Dext was more than 16 mm in Group I and less than or equal to 16 mm in Group III. Five of six patients in Group III underwent myelography. Based on myelographic findings, Group III was further subdivided into two groups, Group IIIA (N = 2) and Group IIIB (N = 3), according to the following characteristics: In Group IIIA, the distance from the os to the posterior arch of the atlas was more than 13 mm, and the spinal cord was impinged between the os odontoideum and the lamina of the axis in extension and reduced in flexion. In Group IIIB, Datl was less than or equal to 13 mm, and the spinal cord was compressed at the level of the atlas during flexion and extension. Stenotic Datl of 13 mm or less specifically defined severe cervical myelopathy. Surgical treatment for cervical myelopathy in os odontoideum with posterior instability is suggested as follows: in the absence of canal stenosis of the atlas (Group IIIA), atlantoaxial fusion in a reduced position is indicated; when associated with canal stenosis of the atlas (Group IIIB), laminectomy of the atlas followed by occiput-to-C2 arthrodesis is indispensable.     

Synovial cyst of the transverse ligament of the atlas in a patient with os odontoideum and atlantoaxial instability

STUDY DESIGN: A case report and review of the literature. OBJECTIVE: To describe the diagnosis and successful treatment of a synovial cyst arising from the transverse ligament in a patient with os odontoideum and atlantoaxial instability. SUMMARY OF BACKGROUND DATA: Synovial cysts arising from the transverse ligament of the atlas are extremely rare. Development of a synovial cyst is thought to be attributable to degenerative changes of the C1-C2 facet joints or to microtrauma. Direct excision of the cyst is the only treatment cited in previous reports. METHODS: A synovial cyst arising from the transverse ligament of the atlas in a 45-year-old man with os odontoideum and atlantoaxial instability was treated surgically with posterior atlantoaxial fusion alone. The magnetic resonance images, surgical treatment, and related literature are reviewed. RESULTS: Preoperative magnetic resonance images of the cervical spine showed a large cystic mass located ventral to the cord arising at the level of the transverse ligament of the atlas: the mass was of low signal intensity on T1-weighted images, was of high signal intensity on T2-weighted images, and was enhanced marginally with gadolinium-DTPA on T1-weighted images. Spontaneous regression of the cyst was identified on the follow-up magnetic resonance images taken 3 months after C1-C2 posterior wiring and fusion. CONCLUSIONS: A patient with a synovial cyst arising at the C1-C2 junction ventrally at the level of the transverse ligament showed spontaneous regression of the lesion after C1-C2 posterior wiring and fusion.     

Spontaneous bone graft resorption in os odontoideum.

Two children are presented who had posterior fusion of the upper cervical spine for os odontoideum. Both patients achieved radiographic fusion but spontaneous bone graft resorption occurred, resulting in a recurrence of the original instability. An awareness of this phenomenon, which has been rarely reported, is important in the pre-operative counselling and postoperative follow-up of these patients.     

Upper cervical ligament testing in a patient with os odontoideum presenting with headaches

STUDY DESIGN: Resident's case problem. BACKGROUND: The role of premanipulative testing of the cervical spine is an area of controversy, and there are very few data to inform and guide practitioners on the use of ligamentous stability tests when assessing the upper cervical spine. DIAGNOSIS: A 23-year-old female was referred to physical therapy by a neurologist for the management of intractable headaches of possible musculoskeletal origin. Her Neck Disability Index score was 54% and she rated her headache pain from 3/10 to 9/10 on a Numerical Pain Rating Scale. She reported a 2-year history of intermittent lower extremity paresthesias without a known mechanism or current symptoms. She was treated in physical therapy for 11 visits with improvements in cervical range of motion, strength, and intensity of her headaches, but noted no change in the frequency of headaches. She was subsequently referred to the primary author for a second opinion and potential manual therapy interventions. Initial neurological screening examination for upper and lower motor neuron lesions was unremarkable. Assessment of the transverse ligament, using the anterior shear test in supine, brought on paresthesias in both feet and her toes. The paresthesias continued after the cessation of the test. The Sharp-Purser test performed in sitting, immediately after the transverse ligament test, abolished the paresthesias. She was then referred back to her primary care physician for further evaluation. Subsequent radiographs and magnetic resonance imaging revealed that the patient had a C2-C3 Klippel-Feil congenital fusion and os odontoideum. The patient was examined by a neurosurgeon who concluded that she was not a surgical candidate. Her neurological symptoms completely resolved, but she continued to have headaches. DISCUSSION: Os odontoideum is a clinically important condition, given that the mobile dens may render the transverse ligament incompetent, leading to atlantoaxial instability. Both the role and sequencing of upper cervical ligamentous testing is controversial. The results of this case report suggest that physical therapists should be cognizant of this condition and consider screening the upper cervical ligaments prior to manual or mechanical interventions to this region. LEVEL OF EVIDENCE: Differential diagnosis, level 4.     

Atlantoaxial instability treated with transarticular screw fixation

We treated 11 patients with atlantoaxial instability using transarticular posterior screw fixation and lateral bone grafting. A posterior bone graft was added in eight patients. The results showed good reduction and a stable fixation. After 6 months ten patients had regained almost 70% of rotation and did not notice any significant limitation.     

Atlantoaxial instability in mucopolysaccharidosis type VII

We report a 15-year-old boy with mucopolysaccharidosis (MPS) Type VII (Sly disease) who was found to have atlantoaxial instability with quadriparesis. Subluxation of C1 on C2 has also been documented in patients with Type I and Type IV MPS. Routine screening of the cervical spine is recommended in patients with "MPS Type VII" so that delayed diagnosis of instability, which may lead to neurologic compromise, is avoided.     

Haemomediastinum in a haemophiliac after minor trauma

Haemomediastinum is a very rare complication in haemophilia. Its occurrence after a minor chest injury in a boy aged 11 years is described. Complete recovery followed conservative treatment, which consisted of the correction of the coagulation defect with cryoprecipitate-AHG for 11 days, and a blood transfusion.     

Collet-Sicard syndrome after minor head trauma

Occipital condyle fractures are rare and are usually associated with severe head and cervical spine injury. A 71-year-old man developed unilateral palsies of the 9th through 12th cranial nerves (Collet-Sicard syndrome) due to a fracture of the occipital condyle, which was diagnosed by computed tomography. He was treated conservatively and made a good recovery.     

寰枢椎椎弓根钉棒固定融合治疗上颈椎不稳

目的探讨经寰椎和枢椎椎弓根钉棒固定融合治疗上颈椎不稳的临床疗效。方法对17例上颈椎损伤致上颈椎不稳患者进行后路经寰椎和枢椎椎弓根钉棒系统复位内固定,使寰枢椎复合体得到稳定,在寰枢椎后弓间植骨融合。结果无术中、术后并发症,有神经症状者得到改善。患者均获随访,时间6～25个月,所有患者后伸活动无障碍,左右旋转功能略受限。X线示螺钉位置良好。无钉棒断裂,螺钉松动,脱落等现象。均在3～4个月获得骨性融合。结论利用寰椎和枢椎椎弓根螺钉通过钉棒连接能显著增强寰枢椎间生物力学稳定性,也能达到一定程度的复位,适用于上颈椎损伤稳定性重建的治疗。     

游离齿状突并发寰枢关节脱位的治疗策略及疗效分析

目的:探讨游离齿状突并发寰枢关节脱位的治疗策略并观察其临床疗效.方法:回顾性分析2006年1月至2015年1月手术治疗的17例齿状突游离小骨并发寰枢关节脱位患者的相关资料,其中男7例,女10例;年龄17～53(43.1±11.3)岁;病程3～27(10.2±6.9)个月.所有患者术前予颅骨牵引,14例可复性脱位患者中1...