Diaphragm thickness and excursion in lumbopelvic pain
This study found significant bilateral reductions in diaphragm thickness during inspiration and in the difference between inspiration and expiration in the right hemidiaphragm in athletes with nonspecific lumbopelvic pain (LPP) lasting for over 6 weeks.
No other parameters showed significant differences, including those related to the left hemidiaphragm and breathing patterns. The presence of LPP was a significant predictor of right and left hemidiaphragm thickness during inspiration.
LPP is an extremely common complaint in athletes. The relevance of trunk muscle activity patterns in athletes with LPP has been extensively studied; however, there is a lack of research about diaphragm morphology and muscular activity in athletes with such complaints and the role od the diaphragm in trunk stabilization remains poorly understood.
Forty athletes participated in this case-control study; 20 with nonspecific LPP lasting for over 6 weeks and 20 matched healthy controls. There was no heterogeneity between groups except for the level of disability caused by the LPP. Diaphragm thickness and excursion were assessed during relaxed respiratory activity (maximum inspiration, maximum expiration, and inspiration-expiration difference) by trans-costal and trans-hepatic ultrasound, respectively.
Despite the small sample size, moderate to large effect sizes were found for the comparisons showing significant differences.
Given the lack of studies on the ultrasound diaphragmatic measurements in athletes with LPP, the authors recommend that these findings should be interpreted with caution and serve as a basis for future longitudinal studies.
Expert opinion by José Pedro Correia
As highlighted by the authors, the results of this study should serve more as a starting point for more robust studies on this topic.
Nevertheless, it provides some interesting insights on diaphragmatic changes in lumbopelvic pain, which are frequently overlooked when evaluating and managing athletes with these complaints. Naturally, since this is a cross-sectional study, no causal relationship can be established.
> From: Calvo-Lobo et al., Phys Ther Sport 37 (2019) 128-137 (Epub ahead of print). All rights reserved to Elsevier Ltd. Click here for the online summary.