【摘要】 慢性压迫性颈脊髓病的发病机制尚未澄清。本文采用经下位颈椎椎体套管状螺钉造成７只杂种犬颈脊髓的慢性渐进性压迫，椎管侵占率达３５．６％～９０．１％，脊髓压迫比率达２７．５％～６２．２％。组织病理学检查证实，受压节段及其相邻部颈脊髓灰白质发生了损害。白质出现片状脱髓鞘区，伴小血管数量增多，管壁增厚，与灰质相邻区域最为常见；压迫较重者，侧索内出现“应力性裂隙”，反映了机械性“锚固效应”的作用。灰质主要表现为神经细胞的退变脱失，以前角运动神经元改变最为显著。微血管造影证实脊髓受压部呈“透亮区”，灰白质境界渐模糊甚至消失，提示发生了血液循环障碍。同时观察到：（１）脊髓表面动脉受到螺钉与椎管后壁间的机械致压，充盈不良；（２）受压节段以下脊髓表面静脉发生淤滞。此可能与受压节段血液循环障碍有关。更多还原

【Abstract】 Chronic progressive spinal cord compression was produced in 7 mongrel dogs by advancing a dual screw through the anterior portion of the lower cervical vertebrae into the spinal canal. The canal encroachment rate was 35.6%￣ 90. 1%. The spinal cord compression ratio ranged from 27. 5% to 62. 2%. Histopathological studies showed abnormalities in the compressed segment and its neibourhoed. The most profound morphological changes occurred at the site of the greatest compression. The main change in the white matter is irregular patchy demyelination accompanied with the vascular changes, which is commonly seen in the area adjacent to the grey matter. "The stress fissure" was demonstrated in the lateral column of the greater compression. and this reflected the mechanically anchoring effect. Within the grey matter.nerve cell degeneration and loss occurred, this was most clearly manifest of motor neurons. Microangiography shoewd circulatory disturbances at the compression site.Meanwhile. the following henomena were observed: (1)The arteries on the surface of the spinal cord wereecompressed by the mechanical force between the anterior screw and the posterior wall of the spinal canal. (2)Venous stasis was observed on the surface of spinal cord below the level of compression.Both of them may provide a basis of the circulatory disturbances associated with chronic cervical cord compression. Author’ s address (Orthopaedic Department of the 3rd Hospital of Beijing Medical University,BeiJing,1 00083)更多还原