Ultrasonography comparison of diaphragm thickness and excursion between athletes with and without lumbopelvic pain.

Objective: The aim of this study was to compare diaphragm thickness and excursion between athletes with and without lumbopelvic pain (LPP) by trans-costal and trans-hepatic rehabilitative ultrasound imaging (RUSI), respectively.

Design: A case-control study.

Setting: Amateur and semiprofessional athletes teams.

Participants: Forty matched-paired athletes with LPP (n = 20; LPP case group) and without LPP (n = 20; Healthy control group) were recruited.

Main Outcome Measures: Diaphragm thickness and excursion (cm) were assessed during relaxed respiratory activity (maximum inspiration-T, expiration-T and difference-T) by trans-costal and trans-hepatic rehabilitative ultrasound imaging (RUSI), respectively.

Results: Statistically significant differences (P < .05) with an effect size from moderate to large (d = 0.63-1.07) were shown for bilateral diaphragm thickness reductions at T and thickness difference at T-T of the right hemi-diaphragm for athletes with LPP compared to healthy athletes.

Conclusions: Athletes who suffered from LPP presented a reduced diaphragm thickness compared to healthy matched-paired athletes. Therefore, these novel findings may suggest that diaphragm reeducation could be a main focus of intervention related to athletic performance, prevention and rehabilitation. Nevertheless, these findings should be considered with caution due to the possible influence of the RUSI measurement errors of the diaphragm activation during normal breathing.