The reliability of displacement measurement of the deep fascia using ultrasonographic imaging

Abstract

In the present research, we studied the reliability of displacement measurement of the deep fascia in the superficial layer and the deep layer of vastus lateralis muscle. We measured 20 lower extremities of 10healthy males with no significant medical history of orthopedic disease. With regard to measurement conditions, in the passive exercise movement of flexed position of knee joint 0 to 45 degree in sidelying, moving distances of superficial layer and deep layer fascia in vastus lateralis muscle was measured with. The reliability of measurements, we used interclass correlation coefficient (ICC), Bland-Altman analysis, and 95% confidence interval (MDC_<95>) of the minimum detectable change (MDC), we studied intra-class and inter-class reliability, as well as type and quantity of measurement errors. As a result, in superficial layer ICC was ICC(1,1)=0.98 and ICC(2,1)=0.98, while in deep layer it was ICC(1,1)=0.98 and ICC(2,1)=0.95. No systematic error was found for intra-class and inter-class reliability. Results of MDC_<95> in superficial layer were, intra-class=0.77mm and inter-class=0.63mm, while in deep layer, intra-class=1.43mm and inter-class=1.96mm. We could confirm that variation of less than 0.77mm in the superficial layer and less than 1.96mm in the deep layer was due to measurement error.