CROSS--SECTION AREAS AND VOLUMES OF THE SPINAL CORD SEGMENTS OF CHINESE / 解剖学报

ABSTRACT

The segment length,the length of dorsal root attachment of each segment of the spinal cord of 10 adult men were measured.The cross sections from 4 specimens were stained with 1% osmic acid and the area of each section was measured with a com- pensating polar planimeter after being magnified 10 diameters.The segment volume was obtained by multiplying the segment length by the cross-sectlon area. The results shows that the length of spinal cords in Chinese are essentially the same as those from European and Japanese.They are approximately 44cm.in length. The length of each part of the cord in Chinese,European and Japanese were compared. The length of each part of the cord in Chinese and European are essentially alike,but the length of lumbar cord of Japanese appears to be slightly longer. The results show that the weight of the segment was closely related to the segment length. The coronal diameter of each segment is longer than the sagittal diameter,especial- ly it is true in the cervical enlargement.The longest coronal and sagittal diameters are found in the cervical enlargement,the next are in the lumbar enlargement,and the shortest are in the thoracic segment. The volume of the cervical segment and the lumbo-sacral segment is closely rela- ted to their cross-section area particularly to the area of their white matter. The volume of the gray matter of the cervical and the lumbo-sacral segments has a close relation to the gray matter area of the same segment,but that of the thoracic segment is related to its length. It is quite obvious that the volume of the white matter of both the cervical and lumbar enlargements reaches its highest value at segments higher than that of the gray matter,which may indicate that the increase in volume in the gray and white matter are dependent upon each other.