Doherty B J, Heggeness M H
Department of Orthopedic Surgery, Baylor College of Medicine, Houston, Texas, USA.
Spine (Phila Pa 1976). 1995 Mar 1;20(5):513-7. doi: 10.1097/00007632-199503010-00002.
While the gross anatomy of the second cervical vertebra has been well described qualitatively, our evolving understanding of spinal pathology makes it necessary for the modern surgeon to have more quantitative information.
The authors' goal was to directly measure clinically relevant dimensions of the second cervical vertebra, using a collection of anatomic specimens.
Many existing studies have been based on analysis of radiographic images, which are subject to errors of magnification, rotation, and projection. Several recent studies of dens morphology have been based on direct measurements. These studies in general did not extend to the lateral masses or posterior ring, however.
Direct measurements using digital calipers and goniometer were taken from 51 dried human second cervical vertebrae. The maximum and minimum anteroposterior and lateral diameters of the dens, and the anteroposterior and lateral diameters of the end-plate and foramen and were measured. The heights of the dens and superior facet surfaces were measured relative to a plane defined by the anterior-most point of the inferior endplate and the inferior-most points of the inferior facet surfaces.
The greatest variation was found in the dens angle, with specimen dens angles ranging from -2 degrees to 42 degrees. The most significant correlations were between the total height of the vertebra and the height to the base of the dens (r2 = 0.81), between the total height of the vertebra and the maximum lateral diameter of the dens (r2 = 0.77), and between the minimum lateral diameter of the dens and the maximum lateral diameter of the dens (r2 = 0.63).
The dimensions measured in this study confirm a significant degree of anatomic variation in the second cervical vertebra, and show no important correlations among the various measured dimensions. In particular, no significant correlation was found between dens height and canal diameter. Dens angle in the sagittal plane was the most variable measurement.
虽然第二颈椎的大体解剖结构已得到定性的详尽描述，但随着我们对脊柱病理学的认识不断发展，现代外科医生需要更多的定量信息。
作者的目标是通过一系列解剖标本直接测量第二颈椎的临床相关尺寸。
许多现有研究基于对X线影像的分析，而这些影像存在放大、旋转和投影误差。最近有几项关于齿状突形态的研究基于直接测量。然而，这些研究一般未涉及侧块或后环。
使用数字卡尺和测角仪对51个干燥的人类第二颈椎进行直接测量。测量齿状突的最大和最小前后径及横径、终板和椎间孔的前后径及横径。相对于由下终板最前点和下关节面最下点所确定的平面，测量齿状突和上关节面的高度。
齿状突角度变化最大，标本的齿状突角度范围为-2度至42度。最显著的相关性存在于椎体总高度与齿状突基部高度之间（r2 = 0.81）、椎体总高度与齿状突最大横径之间（r2 = 0.77）以及齿状突最小横径与最大横径之间（r2 = 0.63）。
本研究测量的尺寸证实了第二颈椎存在显著程度的解剖变异，且各测量尺寸之间未显示出重要的相关性。特别是，未发现齿状突高度与椎管直径之间存在显著相关性。矢状面的齿状突角度是变化最大的测量值。
