Purpose To compare the difference of cervical alignment between cervical lateral radiograph and whole-spine lateral radiograph by the effects of radiographic position and to assess the effect of the shoulder flexed position to cervical lordotic curvature and head position.
Materials and Methods We retrospectively evaluated 43 asymptomatic adult patients who were taken horizontal gazing standing cervical and whole-spine lateral radiograph simultaneously from Sep. 2008 to Dec. 2009. Cervical lateral radiograph was taken with the arms extended and hand gently clasped on both side and whole-spine lateral radiograph was taken in the position that subject were relaxed standing with fists-on-clavicles position. Cervical sagittal alignment were analyzed the following parameters. (1) Gore angle (GA, C2-7 angle); (2) Cobb angle (CA, C2-7 angle); (3) translation distance (TD, distance of C2 compared with vertical line through the posterior-inferior body of C7); (4) McGregor angle (MA, angle between McGregor line and horizontal line).
Results The mean of GA and CA in cervical radiograph were -12.64° and -9.96°, whereas -7.12° and -4.98° in wholespine radiograph. The mean TD and MA were in cervical radiograph were 16.95mm and 7.15°, whereas, 14.97mm and 6.54° respectively in whole-spine radiograph.
Conclusion Our study showed the significant differences of cervical alignment and head position between standing cervical lateral and whole-spine lateral radiograph. The radiographic posture of whole-spine lateral radiograph with horizontal gazing and fists-on-clavicles position make cervical alignment and head position less lordotic and posterior translation compared to cervical radiograph.
