Effectiveness of Diaphragm Release and Doming Techniques on Diaphragmatic Function in Pulmonary Diseases: A Systematic Review

Objective: To evaluate the effectiveness and safety of diaphragm doming (stretching) and manual diaphragm release techniques on diaphragmatic function and related clinical outcomes in pulmonary diseases. Methods: A systematic review of randomized controlled trials was conducted across PubMed, Embase, PEDro, ScienceDirect, AMED, and CINAHL through 2025, following PRISMA guidelines. Eligible studies enrolled adults with obstructive or restrictive pulmonary conditions and compared doming or manual release with usual care, sham, or other respiratory interventions. Primary outcomes included exercise capacity, chest expansion, lung function, inspiratory/expiratory pressures, dyspnea, and ultrasound-derived diaphragm mobility. Methodological quality was assessed using the PEDro and Cochrane RoB tools. Results: Seven trials (n = 387) in inpatient and outpatient settings met criteria. Across COPD, post-COVID-19, and severe pneumonia, both techniques consistently improved 6-minute walk distance, chest expansion, diaphragmatic excursion, dyspnea scores, and, in several studies, FEV1/FVC and inspiratory muscle strength. No serious adverse events were reported. Study quality was moderate to high overall, with common limitations in participant/therapist blinding and variable allocation concealment. Conclusion: Diaphragm doming and manual release are safe, feasible adjuncts that enhance functional capacity, respiratory mechanics, and symptoms in pulmonary disease. Integration within multidisciplinary pulmonary rehabilitation is supported; larger, rigorously blinded trials should refine protocols and longterm effects.