ABSTRACT
Background and Objective: One of the most common postural abnormalities which is seen in 60 percent of patients with neck and shoulder disorders is Forward head posture. The purpose of current study was the comparison of contribution ratio in scapular rotator muscles over dominant and non-dominant arm abduction on loading in women with and without Forward Head Posture
Materials and Methods: In this case-control study 18 women with Forward Head Posture and 14 healthy women were studied. The subjects were matched based on weight, height, age, dominance of upper extremity and voluntarily participated. The contribution ratio of Serratus Anterior, Upper and Lower Trapezius muscles were recorded by surface electrodes during arm abduction with loading
Results: The independent t-test results revealed that the upper trapezius muscle activity ratio of dominant arm in subjects with forward head posture is significantly greater than healthy ones [P=.011], whereas the significant difference was not revealed in non-dominant arm. There were also no significant differences in Serratus Anterior muscle [p>.05] and Lower Trapezius muscle [p>.05] ratio between the groups
Conclusion: Because of the changes in contribution ratio of Upper Trapezius, a simple assessment of head posture through the shoulder muscles can provide useful information for the examiner to decide on prescription of corrective exercises for patient
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