Morphologic Differences in Intervertebral Foramina: A Radiographic Study of Cervical Spine Positions in Asymptomatic Men

Abstract Objective The purpose of this study was to investigate morphologic differences using plain film radiographs in cervical intervertebral foramina (IVF) for the following positions: neutral; flexion combined with lateral flexion to the right, rotation to the left (FLFR-RL); and flexion combined with lateral flexion to the right, rotation to the right (FLFR-RR.) Methods Fifteen participants (male; age, 22-29 years) with no history of neck pain were recruited to participate in this study. Radiographs were taken with participants standing and their cervical spines positioned in neutral, in FLFR-RL, and in FLFR-RR. Foraminal height and width were measured at levels C5/6 and C6/7 by a radiologist. Differences in IVF sizes between positions were analyzed. Results The FLFR-RL position (flexion with contralateral rotation and lateral flexion) increased IVF height at C5/6 by 2.40 mm (24 %; P < .01) and C6/7 by 2.64 mm (26%; P < .01) compared with the neutral position. However, no significant increase in foraminal width was observed compared with the neutral position ( P > .05), and no significant difference in foraminal height and width increase was observed between FLFR-RL and FLFR-RR. Conclusion The results of this study demonstrate that the cervical FLFR-RL position increases the height of the cervical IVF as measured on radiographs.