Morishita Yuichiro, Hida Shinichi, Miyazaki Masashi, Hong Soon-Woo, Zou Jun, Wei Feng, Naito Masatoshi, Wang Jeffrey C
Department of Orthopaedic Surgery, University of California at Los Angeles, Los Angeles, CA, USA.
Spine (Phila Pa 1976). 2008 Mar 15;33(6):E178-82. doi: 10.1097/BRS.0b013e318166f059.
The sagittal kinematics of the cervical spine was evaluated using kinematic magnetic resonance imaging (kMRI).
To investigate the effect of degenerative changes in the functional spinal unit on cervical kinematics by using kMRI.
Few studies have, thus far, by using MR images, described the contribution of degenerative changes in the functional spinal unit to cervical kinematics; however, the exact cervical kinematics remains uncertain.
A total of 289 consecutive symptomatic patients underwent dynamic cervical MRI in flexion, neutral, and extension postures. All digital measurements and calculations of the variations in segmental angular motion were automatically performed by an MR analyzer using true MR images with 77 predetermined points marked on each image. Each segment was assessed based on the extent of intervertebral disc degeneration (Grades 1-3) and cervical cord compression (groups A-C) observed on T2-weighted MR images.
The segmental mobility of the segments with severe cord compression and moderate disc degeneration tended to be lower than that of the segments with severe cord compression and severe disc degeneration, and a significant difference was observed in the segmental mobility of the C5-C6 segment. Moreover, in all segments with moderate disc degeneration, the segmental mobility was significantly reduced in the presence of severe cord compression, as compared with no compression. However, in segments with severe disc degeneration, no significant differences were observed between the segmental mobility of the cord compression groups.
Our results suggest that cervical cord compression may cause deterioration of cervical cord function and kinematic changes in the cervical spine. We hypothesize that the spinal cord may potentially protect its functions from dynamic mechanical cord compression by restricting segmental motion, and these mechanisms may be closely related to the intervertebral discs.
采用运动磁共振成像（kMRI）评估颈椎矢状面运动学。
运用kMRI研究功能性脊柱单元退变对颈椎运动学的影响。
迄今为止，很少有研究通过磁共振成像描述功能性脊柱单元退变对颈椎运动学的影响；然而，确切的颈椎运动学仍不确定。
共289例连续的有症状患者在颈椎前屈、中立和后伸位进行动态磁共振成像检查。所有节段角运动变化的数字测量和计算均由磁共振分析仪使用每个图像上标记有77个预定点的真实磁共振图像自动完成。根据T2加权磁共振图像上观察到的椎间盘退变程度（1 - 3级）和颈髓受压情况（A - C组）对每个节段进行评估。
严重脊髓受压且中度椎间盘退变节段的节段活动度往往低于严重脊髓受压且严重椎间盘退变节段，C5 - C6节段的节段活动度存在显著差异。此外，在所有中度椎间盘退变节段中，与无受压情况相比，严重脊髓受压时节段活动度显著降低。然而，在严重椎间盘退变节段中，脊髓受压组之间的节段活动度未观察到显著差异。
我们的结果表明，颈髓受压可能导致颈髓功能恶化和颈椎运动学改变。我们推测脊髓可能通过限制节段运动来潜在地保护其功能免受动态机械性脊髓受压影响，并且这些机制可能与椎间盘密切相关。
