The ACDF procedure itself can induce regional slope change (C5-s and C7-s) directly at the surgical level and can also influence upper cervical slope change (C1-s and C2s) indirectly. Then the change in the upper cervical spine can induce a change in the St-CVA and spino-cranial angle (SCA).

ObjectiveThe purpose of this study was to investigate morphological change at the craniovertebral junction (CVJ) region using computed tomography.MethodsA total of 238 patients were included in this study, and mean age was 47.8±21.3 months. Spinal canal diameter, Power's ratio, McRae line, antero-posterior C1 ring height, atlantoaxial joint space, C2 growth, epidural space from the dens (M-PB-C2) and longitudinal distance (basion to C2 lower margin, B-C2) were measured. The mean value of each parameter was assessed for individual age groups. The cohorts were then divided into three larger age groups : infancy (I) (≤2 years), very early (VE) childhood (2-5 years) and early (E) childhood (5≥ years).ResultsSpinal canal diameter increased with age; however, this value did not increase with statistical significance after VE age. A significant age-related difference was found for all C2 body and odontoid parameters (p<0.05). Mean McRae line was 8.5, 8, and 7.5 mm in the I, VE, and E groups, respectively. The M-PB-C2 line showed up-and-down dynamic change during early pediatric periods.ConclusionExpansion of the spinal canal was restricted to the very early childhood period (less than 5 years) in the CVJ region; however, the C2 body and odontoid process increased continuously with age. The above results induced a dynamic change in the M-PB-C2 line. Although C2 longitudinal growth continued with age, the McRae line showed relatively little change.

The direct OC screw fixation was not possible in a considerable number of cases due to the limited space and the position of the VA regardless of age group. Only about one quarter (21-24 %) of all patients was affordable to place the direct OC screw bilaterally. There was more space available to place the direct OC screw when the angle of the upper cervical spine is more kyphotic.

Intramuscular myxoma (IM) is a benign neoplasm of mesenchymal origin. We report a rare case of IM which was located in the lumbosacral paraspinal muscles. A 62-year-old female patient presented with progressive low back pain for 2 months, and the radiologic findings showed a large mass (4.0×3.5×6.5 cm) in the right lumbosacral paraspinal area. Total resection of the tumor was performed and the symptom was nearly resolved after surgery. Although the immuno-histopathological analysis was consistent with IM, there were some different findings from typical pathological characteristics of IM in this case. Firstly, the symptomatic change of the mass took relatively short time (less than 3 months), and this change was accompanied by partial calcification inside the mass. Moreover, iatrogenic interruption of paravertebral muscle by the other previous operation might be the promoting factor of the fibrous dysplasia, which can explain the pathogenesis of IM. To our knowledge, this is the eighth case of the lumbar paraspinal myxoma reported in the literatures and the first case in Asian population.

Spinal neurenteric cysts are uncommon congenital lesions, furthermore solitary neurenteric cysts of the upper cervical spine are very rare. A 15-year-old boy having an intraspinal neurenteric cyst located at cervical spine presented with symptoms of neck pain and both shoulders pain for 2 months. Cervical spine magnetic resonance (MR) imaging demonstrated an intradural extramedullary cystic mass at the C1-3 level without enhancement after gadolinium injection. There was no associated malformation on the MR imaging, computed tomography, and radiography. Hemilaminectomy at the C1-3 levels was performed and the lesion was completely removed through a posterior approach. Histological examination showed the cystic wall lined with ciliated pseudostratified columnar epithelium containing mucinous contents. Neurenteric cyst should be considered in the diagnosis of spinal solitary cystic mass.