Immediate Effect of Thoracic Thrust on Diaphragmatic Excursion in Subjects with Forward Head Posture - A Pre-Test and Post-Test Experimental Design

Background and Objectives: Forward head posture (FHP) is a postural dysfunction caused by anterior translation of the head leading to an increase in craniovertebral angle caused by a narrowed lower chest and expanded upper chest which limits the diaphragmatic excursion. FHP occurs as a compensatory mechanism to improve respiratory functions or to change the thorax morphologically (i. e., kyphotic posture). FHP mechanical effects on the diaphragm and chest wall result in diminished thoracic compliance and impaired diaphragmatic excursion. Thoracic spine manipulation releases chest wall restriction the mechanical changes in the lungs were reversed via a hysteresis-like pathway. Thus, any abnormality that affects the muscle of respiration or rib biomechanics will have an effect on the optimal functioning of the lungs. Methodology: 40 subjects with forward head posture aged between 20-40years were selected. A single group pre-test and post-test experimental study design was used to examine thoracic spine thrust manipulation effects on chest expansion and lung function in healthy subjects. Ethical approval was granted by Manipal Hospitals private limited, Yeshwanthpur, Bangalore, Karnataka, India. Subjects with forward head posture was assessed and diaphragmatic excursion was measured before and after thoracic thrust. Differences between pre and post thrust was assessed and statistical tool was used for the statistical analysis. Results: The result shows that there is a significant difference between pre-thrust and post-thrust with p<0.000. As the sig. (2-tailed) value is 0.00 which is less than 0.05, the result is interpreted as significant. Hence, the null hypothesis is rejected. Conclusion: The present study concludes there was significant immediate difference in diaphragmatic excursion between pre and post thoracic thrust. Hence, this study concludes that thoracic thrust can improve diaphragmatic excursion in subject with forward head posture.