上颈段颈椎脊髓病

Spondylotic Myelopathy in the Upper Cervical Spine

目的：一般认为颈椎脊髓病好发于下颈段，Ｃ５６最常见，其次为Ｃ６７。有时上３个颈椎受累，由于神经系统病变定位困难，尤其ＭＲＩ应用于临床前的影像学缺欠，常使上颈段脊髓病被误认作下颈段病变。本文旨在说明上颈段脊髓病的发病，病理及神经系统症状特点。方法：对１５６例颈椎脊髓病中２８例上颈段病变的临床表现、影像学特点、手术所见及随访结果作了研究。诊断依据为肱二头肌腱反射亢进，试图引出肱二头肌或肱桡肌反射时，出现活跃的反向桡反射，并结合ＭＲＩ定位。结论是：（１）上颈段颈脊髓病并非少见，实际上的发病比例较以前报道为高，理由是：（ａ）有时上颈段病变不出现肱二头肌反射亢进，（ｂ）早年病例难以取得明确的影像学证据，（ｃ）定位诊断不明确者不记入本组。（２）肱二头肌腱反射亢进及活跃的桡反射代表第５颈髓节段以上病变，因此可作为相应Ｃ３４椎以上的病变定位体征。（３）ＯＰＬＬ常在上颈段显著，骨化可累及寰枢后韧带复合。（４）长久退变的上颈段脊髓病常显示颈椎生理曲线折断，提示不稳定，不稳定椎间承受集中应力，其连接结构椎间盘和黄韧带增生肥厚，导致椎管狭窄。（５）椎管后壁突入是上颈段脊髓病的重要病理改变。（６）神经系统定位检查应为主要的诊断?

Objectives: Because of imaging defects especially before the use of MRI, spondylotic myelopathy of the upper cervical spine(CSM) are not well recognized. The authors analyzed 28 cases of lesions of the upper cervical spine among 156 cases of CSM in order to ascertain the pathogenetic, pathologic and the neuralogic features. Methods: The clinical manifestations, imaging studies, the surgical findings and the followup results in 28/156 cases of CSM at the high levels of cervical spine were reviewed. The hyperresponsive biceps reflex, the active inverted radial reflex during elicitation of biceps and a brachioradialis reflexes and image findings were considered as the diagnostic basis. Conclusion:(1)CSM at high levels of cervical spine(C1～4) are not unusual.(2) Hyperresponsive biceps reflex and active inverted radial reflex suggest the lesion being located at the C34 or a higher levels.(3)OPLL is often obvious at the higher level of the cervical spine. The ossification may involve the posterior ligamenta complex of the atlantoodontoid.(4)Posterior encroachment upon the spinal canal should be an important pathologic composition of CSM in the upper cervical vertebra.(5)and(6)Careful neurologic examinations and image studies are necessary for the localization and the diagnosis of CSM of the upper cervical spine.