The impact of forward head posture on the electromyographic activity of the spinal muscles

OBJECTIVE: This study aims to examine the electromyographic activity of the regional spinal muscle between patients with forward head posture (FHP) and those with a normal cranio-vertebral (CV) angle. METHODS: We recruited 60 adult women aged between 18 and 29 years from a single institution. The CV angle was measured in the sagittal plane, which helped us to assign the participants in the FHP group (n = 30) with a large CV angle (53.1 ± 2.3) and the control group (n = 30) with a normal CV angle (43.0 ± 3.6). The surface electromyography (EMG) was used to measure the magnitude of normalised muscle activity of eight spinal muscles (cervical, lumbar, and thoracic levels) while standing and performing a specific manual handling task. RESULTS: The CV angle was significantly lower in the FHP group than in the control group (p = .001). The cervical erector spinae (CES) muscle activity was significantly increased in the FHP group compared to that in the control group. The right and left CES of those in the FHP group exhibited 73% and 87%, respectively, higher normalised muscle activity than those in the control group while performing the manual handling task (p = .001). No significant difference was detected for the thoracic or lumbar segment muscles between groups. CONCLUSION: Our results indicate that greater neck muscle demands result from anterior head translation in FHP. This effect is a counterbalance to the reduced CV angle and to support the neck. The increased activity of the neck muscles in FHP could demand more support from the neck muscles and might increase the risk of spinal injuries. Management of FHP is essential to avoid overloading the spinal muscles.