COMPARING BETWEEN DEEP NECK FLEXOR MUSCLES CROSS-SECTIONAL AREA IN FORWARD AND NORMAL HEAD POSTURE WITH ULTRASONOGRAPHY

Background: As one of the most common work-related musculoskeletal disorders and postural deviations, forward head posture (FHP) is considered to lead to muscle imbalance.

Purpose: The aim of this study is to investigate the bilateral cross _sectional area (CSA) of the deep neck flexor muscles at the rest and during five stages of the craniocervical flexion (CCF) test in individual with FHP and the controls with normal head posture.

Methods: Eighteen students with FHP and 18 control with normal head posture, all females aged 18 - 35 years, participated in this study. participants were categorized into two groups based on their craniovertebral angle. the CSA of the deep neck flexors was measured using ultrasonography while participants lay supine on the table withe a pressure biofeedback unit placed under their necks in order to let the examiner measure the CSA of the muscles during rest and five stages of the CCF test including 22, 24, 26, 28 and 30 mmHG of the pressure biofeedback unit.

Results: A significant effect of contraction level was observed in both groups, indicating significant increases of the CSA of the deep neck flexors during contractions (F=64.37, P<0.001). No significant difference was evident for the CSA of the deep neck flexors between the groups, although the increase in the CSA of the deep neck flexors was up to 28 mmHG in the normal head posture group compared to 26 mmHG in the FHP group.

Conclusion(s): The result of the present study showed no significant difference between the performance of the deep neck flexors during the CCF test in FHP and normal head posture individuals, which challenge the common belief of the deep neck flexors weakness in individuals sustaining FHP.

Implications: To our knowledge, this study is the first to evaluate the effects of FHP on DNF ultrasonographic morphology while performing the CCF test, the result this study show that by increasing the pressure during the CCF test, the CSAs of the DNFs increased in all stages of the test in both groups. these results  might be of interest to clinicians and researchers interested in managing postural deviations, particularly those related to FHP.

Funding, acknowledgements: This study is financially supported by the University of Social Welfare and Rehabilitation Sciences, Tehran, Iran

Keywords: deep neck flexors, forward head posture, ultrasonography

Topic: Musculoskeletal: spine

Did this work require ethics approval? Yes

Institution: University of Social Welfare and Rehabilitation Sciences

Committee: University of Social Welfare and Rehabilitation Sciences

Ethics number: IR.USWR.REC.1394.35