Neanderthal skulls also show evidence of a large hypoglossal canal. 尼安得特人头盖骨也证明了存在大量的舌下神经管。
These are not derived from the neural crest, instead an outpouching of the neural tube generates the optic cup which, in turn, forms the retina. 不过视网膜上皮的黑色素细胞是其中的例外，它们并非由神经脊产生，而是在神经管外囊生成的视杯产生。
Because the spinal cord is encased within its bony canal, it cannot move away from the pressure and it becomes pinched. 由于脊髓受到骨质椎管的限制，不能避开压迫物，而受到挤压。
At the caudal end of the sacrum the roof of the vertebral canal is commonly deficient. 在骶管末端，椎管往往缺损。
