ABSTRACT
Because of the corrigibility of forward head posture [FHP], the recognition of the relationship between this deformity and scapular rotator muscles may be influential on scapular muscle activities in detection of better way to improve movement disorders. Therefore, the aim of this study was to compare the serratus anterior, upper and lower trapezius muscle contributions during shoulder flexion without weight in women with and without FHP. In this case-control study was carried out on 18 women with FHP and 14 healthy subjects who were matched. EMG muscle activities were recorded during shoulder flexion and abduction. The value of each muscle divided on total muscle values to calculate contribution ratio and independent t-test was used to compare contributions between groups. There was a significant decrease in serratus anterior muscle activity ratio [p=0.002] and a significant increase in upper trapezius muscle activity ratio [p=0.001] between subjects with and without FHP. There was not also significant difference in contribution of lower trapezius muscle. Contribution of the serratus anterior muscle in individuals with forward head posture is less than healthy subjects. The contribution of upper trapezius muscle also in individuals with FHP is greater than healthy subjects