Chest wall mobilization on thoracic excursion and respiratory function in relation to respiratory efficiency and functional capacity in severe COPD: a randomized controlled trial

Chest Wall Mobilization on Thoracic Excursion and Respiratory Function in relation to Respiratory Efficiency and Functional Capacity in Severe COPD: A Randomized Controlled Trial

Amy Y.Y. Tsui a, Gladys L.Y. Cheing b, Rosanna M.W. Chaua, Sharon M.H. Tsangb

a Physiotherapy Department, Kowloon Hospital, Hong Kong
b Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong

Keywords:
Chest Wall Mobilization Techniques
Respiratory Muscle Function
Chronic Obstructive Respiratory Diseases (COPD)

Background and aims: Restricted chest wall mobility with lung hyperinflation in chronic obstructive pulmonary disease(COPD) patients would compromise respiratory muscle efficiency and work of breathing. Chest wall and thoracic spine mobilizations aim to stretch essential respiratory muscles to promote chest wall mobility and enhance respiratory efficiency in COPD patients.

Methods: Thirty male adults(age:74.97±6.29) suffered from severe COPD were recruited in a 6-week pulmonary rehabilitation(PR) programme(twice/week) according to randomisation(chest wall mobilization group, CWMG, n=15; control group, CG, n=15). Both groups received standardized education and walking exercise, while CWMG received additional chest wall and spine mobilisations. Respiratory muscle strength, thoracic excursion, electromyography(EMG) and tissue oxygen saturation(StO2, measured by near-infrared spectroscopy) of respiratory muscles during incremental exercise test were compared between pre-program, post-program, and 3-month follow-up.

Results:
CWMG but not CG showed significant increase in maximum inspiratory and expiratory pressure(p<0.001), and thoracic excursion(p<0.05). Scalene, sternocleidomastoid and intercostal muscles during exercise test exhibited significant decrease in activity(p<0.01) indicates improvement in exercise tolerance in CWMG. Significant decrease in StO2(p<0.05) and greater decline in the slope of oxygenation dissociation(p=0.000) in CWMG indicates significant greater efficiency of oxygen release and delivery to intercostal muscle during exercise. CWMG attained significantly higher level of exercise from <3METS to 4-6 METS(p=0.000). All improvements were well maintained at 3-month follow-up.

Conclusion: Integrated chest wall mobilization into PR shows significant increase in chest expansion capacity which allows respiratory muscles to work at an optimal functional length results in greater respiratory muscle strength and exercise tolerance with enhanced respiratory muscle efficiency and oxygenation dissociation in severe COPD.