The purpose of this study was to assess the influence of the duration of smartphone usage on cervical and lumbar spine flexion angles and reposition error in the cervical spine. The study included 18 healthy smartphone users (7 males and 11 females). We measured the kinematics of the upper and lower cervical and lumbar spine flexion angles and the reposition error of the upper and lower cervical spine after 3 s and 300 s smartphone use in sitting. A paired t-test was used to compare the effects of the duration of smartphone usage on the kinematics of cervical and lumbar spine flexion angles and reposition error. The flexion angles of the lower cervical and lumbar spine and the reposition error in the upper and lower cervical spine were significantly increased after 300 s smartphone of use (p<.05). However, the flexion angle of the upper cervical spine was not significantly different between the 3 s and 300 s smartphone of use (p>.05). These findings suggest that prolonged use of smartphones can induce changes in cervical and lumbar spine posture and proprioception in the cervical spine.

• 김양곤(인제대학교 대학원 물리치료학과) | Yang-gon Kim
• 강민혁(인제대학교 대학원 재활과학과) | Min-hyeok Kang
• 김지원(인제대학교 대학원 재활과학과) | Ji-won Kim
• 장준혁(해운대 자생한방병원 물리치료실) | Jun-hyeok Jang
• 오재섭(인제대학교 의생명공학대학 물리치료학과) | Jae-seop Oh Corresponding author