Stress Fracture of the Anterior Atlas Arch Following C1 Posterior Arch Resection for Cervical Myelopathy with Retro-Odontoid Pseudotumor / 대한정형외과학회잡지

Atlas fracture accounts for 1% to 3% of all spinal column injuries and 10% of cervical spine fractures, and is most frequently caused by motor vehicle accidents and falls. Only a few cases involving complications after surgical treatment have been reported. We present a case of anterior atlas arch stress fracture accompanied by worsening neurologic symptoms following atlas posterior arch resection for cervical myelopathy with retro-odontoid pseudotumor.

Congenital Anomaly of the Atlas Misdiagnosed as Posterior Arch Fracture of the Atlas and Atlantoaxial Subluxation

Partial or complete absence of the posterior arch of the atlas is a well-documented anomaly but a relatively rare condition. This condition is usually asymptomatic so most are diagnosed incidentally. There have been a few documented cases of congenital defects of the posterior arch of the atlas combined with atlantoaxial subluxation. We report a very rare case of congenital anomaly of the atlas combined with atlantoaxial subluxation, that can be misdiagnosed as posterior arch fracture.

Cervical vertebrae morphology in skeletal class Ⅱ and class Ⅰ malocclusion patients / 中国组织工程研究

BACKGROUND:The incidence rate of cervical abnormalities of the patients with skeletal class Ⅱ and normal occlusion has been studied abroad, but the researches on the incidence of cervical abnormalities in different malocclusion patients is rare at home. OBJECTIVE:To observe the imaging of patients with cervical abnormalities and to statistics the incidence of cervical abnormalities in different malocclusion patients through analyzing the lateral cephalogram of different malocclusion patients. METHODS:Skeletal class Ⅱ group was consisted of 93 patients, 41 male (aged 18-40 years) and 52 female (aged 22-35 years), with the A point-nasion-B point angle>5°. Class Ⅰ group was consisted of 45 patients, 31 female (aged 20-36 years) and 14 male (aged 17-38 years), with the 1°

Posterior arch length of individual normal occlusion of adults in Lanzhou / 中国组织工程研究

BACKGROUND:Posterior arch length deficiency is closely related to the formation and development of malocclusion. OBJECTIVE:To measure the posterior arch length in individual normal occlusions of adults in Lanzhou. METHODS:A total of 102 current col ege students with individual normal occlusions, with a mean age of (19.33±2.67) years (range 18-24 years), including 47 males and 55 females from Gansu Province, were chosen to take lateral cephalograms. Al research objects were divided into three groups according to mandibular plane angle:high angle group (Frankfort mandibular-plane angle>32°), low angle group (Frankfort mandibular-plane angleRESULTS AND CONCLUSION:Posterior arch length of maxil ary arch was slightly longer in male group than that in female group, and the difference was not significant (P>0.05). The posterior arch length of mandibular arch was slightly longer in male group than that in female group, but the difference was no significant (P>0.05). Comparison between groups revealed that the posterior arch length of low angle mandibular arch was significantly longer than that of high angle mandibular arch in male group, and the difference was significant (P<0.05). The results indicate that the gender wil not influence the development of posterior arch length. Different vertical facial types and different genders have different posterior arch length in individual normal occlusions of adults

Study of abnormal foramen over the posterior arch of atlas vertebra / Estudio de forámen anormal sobre el arco posterior de la vértebra atlas

The aim of this research was to study the anatomical aspects of abnormal foramen over the posterior arch of atlas vertebra. Posterior arch of atlas vertebrae was studied for abnormal foramen in sixty-seven adult human atlas vertebrae and findings were noted. In 2.98 percent of cases, unilateral complete abnormal foramen on the posterior arch of atlas vertebra was found. Clinicians should be aware about this variation on posterior arch of atlas, which may produce headache, vertigo, vertebrobasilar insufficiency and shoulder pains.

El objetivo fue observar los aspectos anatómicos de un foramen anormal presente sobre el arco posterior del atlas. Se estudiaron 67 vértebras atlas de humanos adultos. En el 2,98 por ciento de los casos, se encontró un foramen unilateral anormal completo sobre el arco posterior del atlas. Los clínicos deben estar conscientes de esta variación anatómicaen , la cual podría producir cefalea, vértigo, insuficiencia vertebrobasilar y dolores en los hombros.

Congenital Absence of the Posterior Arch of the Atlas A Strange but Benign Anomaly

Congenital partial aplasia of the atlas with a posterior arch remnant is rare. It may be found as an incidental radiological finding or patients can present with neurological signs and symptoms after head or neck trauma. A 36 year old female presented with a 3 day history of right sided neck pain radiating down the right arm. Radiographs of the cervical spine showed a radiolucent area in the region of the posterior arch of the atlas. Computed tomography subsequently revealed partial absence of the posterio

Coincidental Congenital Absence of the Posterior Arch of the Atlas and the Unilateral Lumbosacral Articular Process: A Case Report / 대한정형외과학회잡지

We encountered a case of coincidental congenital complete absence of the posterior arch of the atlas and the unilateral lumbosacral articular process. A 21-year-old man presented with pain in the lower back and right buttock. The patient was a swimming coach. On plain radiography, computerized tomography and magnetic resonance imaging, the congenital absence of the unilateral lumbosacral articular process was noted. Six months later, the patient developed severe neck pain and suboccipital headaches without neurological signs. On plain radiography and computerized tomography, the congenital complete absence of the posterior arch of the atlas was noted. Magnetic resonance imaging showed no abnormal signs originating from the posterior spinal cord. There was no segmental instability. For this case, the lower back pain and neck pain were managed by conservative treatment. To the best of our knowledge, this is the first case of a coincidental congenital complete absence of the posterior arch of the atlas and the unilateral lumbosacral articular process.

Efficacy of pedicle screw instrument for treatment of irreducible atlantoaxial dislocation / 中国矫形外科杂志

[Objective]To explore the surgical feasibility and clinical outcome of pedicle screw instrument for treatment of irreducible atlantoaxial dislocation and to choose an effective method of internal fixation.[Method]From June 2003 to February 2009,14 pationts with atlas dislocation followed by upper cervical cord compression were treated surgically with oral anterior soft tissue release combined with posterior reduction and pedicle screw instrument.Preoperative CT,MRI and radiographs as well as intraoperative screw placement and bone graft were administered in all pationts.Only cervical collars were used as external support for 3 months in occipitocervical fusion.[Result]All screws were successfully placed in atlas and axis.Forteen patients were followed up for an average of 18 months.Bone fusion was achieved in all cases with no complications of nerve,internal fixation failure and redislocation.Neurological recovery was significantly improved in 12 cases and took a turn for better in 2 cases.[Conclusion]Pedicle screw instrument in atlas and axis has the advantages of direct screw placement,short-segment fusion,intraoperative reduction and high fusion rate.It is a better alternative for atlantoaxial dislocation.

Cerebellar Ectopia Associated with Unilateral Agenesis of Posterior Arch of Atlas

Chiari type I malformation(CM-I) is a congenital disorder recognized by caudal displacement of the cerebellar tonsils through the foramen magnum and into the cervical canal. Though bony anomalies associated with CM including platybasia, small posterior fossa and occipitalization, are relatively frequent, but the incidence rate associated with agenesis of posterior arch of atlas is very low. We report our experience of surgical treatment for patient who had CM-I with unilateral agenesis of posterior arch of atlas.

Transient Quadriparesis due to Dysgenesis of the Posterior Arch of the Atlas: Case Report

Acase of 14-year-old student is presented with the complaint of recurrent attack of transient quadriparesis during hyperextension of the neck. On 3-dimensional spinal CT and MRI, the authors confirmed intrusion of posterior tubercle of the atlas with increased signal on T1- and T2- weighted image was found. The clinical manifestations were improved without having cervical instability after a posterior laminectomy of the atlas.

Incomplete posterior arch of the Atlas.

Incomplete posterior arch of the atlas was found in a 77 years old Thai cadaver. The length of right posterior arch decreases and the left posterior arch is diminished to be a small process. The intervening space is occupied by a fibrous connective tissue band. The left superior articular facet and the left occipital condyle decrease in size. There are no defects of the spinal cord and its meninges. No abnormal neurological symptom and abnormal movement of the head and neck.