Hellsing E
Eur J Orthod. 1989 Nov;11(4):359-65. doi: 10.1093/oxfordjournals.ejo.a036007.
In a sample of 20 adults the associations between cervical lordosis, craniocervical inclination, position of the hyoid bone and cross-sectional dimensions of the pharyngeal airway were studied. Lateral skull radiographs were obtained in natural head posture and also at 20 degrees extension with the subjects' teeth in the intercuspal position. Cervical lordosis was measured from the second to the sixth vertebra and the position of the hyoid bone was calculated in horizontal and vertical directions. The dimensions of the free airway were measured between the dorsal tongue surface and the posterior pharyngeal wall and at the level of the second and fourth vertebra. A change from natural head posture to 20 degrees extension resulted in an increase in cervical lordosis and craniocervical inclination, changed position of the hyoid bone and increased cross-sectional dimensions of the pharyngeal airway. The changes in lordosis produced by changing natural head posture to 20 degrees extension showed significant correlations with the size of changed craniocervical inclination and free airway.
在20名成年人的样本中，研究了颈椎前凸、颅颈倾斜度、舌骨位置与咽气道横截面积之间的关联。在自然头位以及头部伸展20度且受试者牙齿处于牙尖交错位时获取头颅侧位X线片。测量第二至第六颈椎的颈椎前凸，并计算舌骨在水平和垂直方向上的位置。在舌背表面与咽后壁之间以及第二和第四颈椎水平测量气道的尺寸。从自然头位到伸展20度导致颈椎前凸和颅颈倾斜度增加，舌骨位置改变，咽气道横截面积增大。将自然头位改变为伸展20度所产生的前凸变化与颅颈倾斜度改变的大小和气道尺寸显著相关。
