RESUMO
BACKGROUND: Changes in the orientation of ultrasound (US) transducer relative to the body surface during dynamic standing tests can affect US measurements. OBJECTIVE: The purpose of the study was to evaluate ultrasound imaging transducer motion while measuring the lateral abdominal muscle thickness during standing tasks with and without using transducer fixator (TF). DESIGN: Cross-sectional experimental study. METHODS: A digital optical motion analysis system was used to assess the motions of US transducer during double-leg stance in different levels of platform stability of Biodex Balance System (BBS) (static, levels 6 and 3) with and without using TF in 45 healthy individuals. In addition, lateral abdominal muscle thickness was evaluated by US imaging. RESULTS: The results indicated that the amount of angular and linear transducer motions during static and dynamic standing tasks significantly decreased by the use of TF as compared to the conditions without TF (P < 0.001, effect size> 0.84). CONCLUSION: TF can significantly control US transducer motions within acceptable threshold limits during standing postural task. This may improve the clinical application of US imaging.