Philadelphia versus Miami-J cervical collar's impact on pulmonary function

Purpose: The purpose of this study was to compare the effect of two types of cervical collars (Philadelphia and Miami-J) on pulmonary function and ventilation in healthy volunteers through spirometry, peak flow meter, and capnograph. Method: Initially, subjects were randomized into two groups in which the sequence of collars' fixation was re-versed. Afterward, we assessed the pulmonary parameters without a cervical collar in all participants. Each group underwent two additional test conditions, including measurements after wearing a Philadelphia and Miami-J cervical collar. In any case, we took the measurements half an hour after the collar fixation. Results: The mean age of participants was 48.34 +/- 1.35 years. Following either type of collars application, there was a statistically significant decrease in FEV1, FEV1/FVC, FEF25-75%, and PEF (p < .001). However, FVC was not significantly changed (p = .157). Conclusion: In summary, we noted a statistically significant expiratory flow obstruction after both the Philadel-phia and Miami-J cervical collar. These changes were not clinically significant in healthy volunteers, albeit may have ramifications in patients with pre-existing respiratory compromise. (c) 2021 Elsevier Inc. All rights reserved.