title: Morphometric Relationship between the Cervicothoracic Cord Segments and Vertebral Bodies.
abstract: OBJECTIVE
  The objective of this study was to investigate the morphologic characteristics between the vertebral body and the regions of the cervical and thoracic spinal cords where each rootlets branch out.
  
  
  METHODS
  Sixteen adult cadavers (12 males and 4 females) with a mean age of 57.9 (range of 33 to 70 years old) were used in this study. The anatomical relationship between the exit points of the nerve roots from the posterior root entry zone at each spinal cord segment and their corresponding relevant vertebral bodies were also analyzed.
  
  
  RESULTS
  Vertical span of the posterior root entry zone between the upper and lower rootlet originating from each spinal segment ranged from 10-12 mm. The lengths of the rootlets from their point of origin at the spinal cord to their entrance into the intervertebral foramen were 5.9 mm at the third cervical nerve root and increased to 14.5 mm at the eighth cervical nerve root. At the lower segments of the nerve roots (T3 to T12), the posterior root entry zone of the relevant nerve roots had a corresponding anatomical relationship with the vertebral body that is two segments above. The posterior root entry zones of the sixth (94%) and seventh (81%) cervical nerve roots were located at a vertebral body a segment above from relevant segment.
  
  
  CONCLUSIONS
  Through these investigations, a more accurate diagnosis, the establishment of a better therapeutic plan, and a decrease in surgical complications can be expected when pathologic lesions occur in the spinal cord or vertebral body.
authors.affiliation: Department of Neurosurgery, Soonchunhyang University Hospital, Seoul, Korea.
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Chul Woo
authors.initials: CW
authors.lastname: Lee
authors.forename: Kwon Soo
authors.initials: KS
authors.lastname: Chun
authors.forename: Won Han
authors.initials: WH
authors.lastname: Shin
authors.forename: Hack-Gun
authors.initials: HG
authors.lastname: Bae
authors.forename: Jae Chil
authors.initials: JC
authors.lastname: Chang
keywords: Cadaveric study; Cervical spine; Cord; Nerve root; Spinal; Thoracic spine