Neck postures during smartphone use in university students and office workers: A field study

Office workers and university students are known to suffer from neck pain as they are frequent users of electronic devices. The present study utilized inertial motion sensors to examine real-time spinal kinematics in office workers and university students for 3 h in their natural working/studying environment. Office workers (10 males, 10 females) and university students (11 males, 11 females) were recruited by convenience sampling. Their mean ages were significantly different (Workers: 40.8 ± 8.5 years; Students: 21.5 ± 2.6 years). Five inertial motion sensors (Noraxon myoMotion™) were attached firmly onto the occipital protuberance, and the spinous processes of C6, T3, T12, and the sacrum, respectively, yielding angular displacements of the cervical, upper thoracic, lower thoracic and lumbar segments. The mean postural angles and the number of variations (zero crossings per minute) were analyzed. Self-reported neck pain score was higher in office workers (4.1 ± 3.7 on a 0–10 numeric scale) than that in students (2.3 ± 2.0, P = 0.076). Students adopted significantly greater degrees of lumbar flexion compared with office workers. Conversely, office workers tended to adopt slightly larger neck postural angles than students. Similarly, there was no significant between-group difference in zero crossings for the different spinal segments. Multivariate regression analyses showed that interaction of posture and duration of smartphone use were factors significantly contributing to musculoskeletal symptoms in students (P < 0.001), while age and gender were significant risk factors for symptoms in office workers (P = 0.001).