Three-dimensional change in the cervical spine in a cross-legged sitting position after a time lapse

[Purpose] The purpose of this study was to investigate the kinematic changes of the cervical spine during cross-legged sitting. [Subjects and Methods] In total, 19 healthy participants were recruited from among healthy students of Silla University. Each participant sat cross-legged with the right leg over the left and gazed at a target presented at 45° below the horizontal line of sight or at an object placed directly ahead, at 90° relative to horizontal for 10 minutes. [Results] With the 45° downward gaze, there was no significant difference in cervical angle between the 0–5-min and 5–10-min time periods. However, the angle in the sagittal plane increased with time, while the frontal and transverse plane angles decreased. With the 90° forward gaze, there was no significant difference in cervical angle between the 0–5-min and 5–10-min time periods. However, the frontal plane angle increased as time elapsed, while the sagittal and transverse plane angles increased between 0 and 5 min and decreased between 5 and 10 min. [Conclusion] Our results suggest that prolonged cross-legged sitting could produce malalignment of the cervical spine in three planes of motion.