Human Performance and Sports Science Laboratory. Faculty of Sport Sciences, University of Murcia, Murcia,Spain.
Int J Sports Physiol Perform. 2022 Jul 18;17(10):1480-1488. doi: 10.1123/ijspp.2021-0381. Print 2022 Oct 1.
To analyze the feasibility of the 2-point method for estimating ultrasound-derived quadriceps femoris cross-sectional area (QUADACSA). First, (1) the agreement between QUADACSA measured by panoramic ultrasound and magnetic resonance imaging (MRI) was studied, and thereafter, we examined 2 approaches of the 2-point method in terms of (2) estimation errors and (3) test-retest repeatability.
Both thighs of 16 young men were analyzed. Ultrasound-QUADACSA versus MRI-QUADACSA comparison was conducted at 6 thigh lengths (20%-70% of the thigh length). Thereafter, ultrasound-QUADACSA corresponding to 30% and 60% (2-point30%-60%) or 20% and 70% (2-point20%-70%) were used to estimate QUADACSA of the remaining regions. Estimated QUADACSA resulting from both 2-point approaches was compared with the measured one. Finally, the test-retest repeatability was examined by comparing the errors generated on 2 separate estimations. Statistics included the standard error of measurement (SEM) expressed in absolute (in square centimeters) and relative terms (in percentage) as a coefficient of variation (CV), as well as the intraclass correlation cofficient (ICC) and bias.
An excellent agreement (ICC ≥ 0.980) and reduced errors (SEM ≤ 2.43 cm2) resulted from the ultrasound-QUADACSA versus MRI-QUADACSA comparison. Although estimation errors found were reduced (CV ≤ 7.50%), they proved to be lower and less biased for the 2-point30%-60%, especially at the central regions (SEM ≤ 2.01 cm2; bias ≤ 0.89 cm2). Similarly, repeatability analysis revealed lower test-retest errors for the 2-point30%-60% (CV ≤ 1.9%) than for the 2-point20%-70% (CV ≤ 4.6%).
The 2-point method, especially that implemented using the 30% and 60% regions, represents an accurate and repeatable strategy to evaluate QUADACSA.
分析两点法估计超声股四头肌横截面积（QUADACSA）的可行性。首先，（1）研究全景超声和磁共振成像（MRI）测量的 QUADACSA 之间的一致性，然后，我们检查了两点法的两种方法在（2）估计误差和（3）测试-重测重复性方面的情况。
对 16 名年轻男性的两条大腿进行了分析。在 6 种大腿长度（大腿长度的 20%-70%）处进行超声 QUADACSA 与 MRI-QUADACSA 比较。此后，使用 30%和 60%（2 点 30%-60%）或 20%和 70%（2 点 20%-70%）的超声 QUADACSA 来估计剩余区域的 QUADACSA。两种两点法得出的估计 QUADACSA 与测量值进行比较。最后，通过比较两次独立估计产生的误差来检查测试-重测重复性。统计数据包括以绝对（平方厘米）和相对（百分比）表示的测量标准误差（SEM），作为变异系数（CV），以及组内相关系数（ICC）和偏差。
超声 QUADACSA 与 MRI-QUADACSA 比较得到了极好的一致性（ICC≥0.980）和较小的误差（SEM≤2.43cm2）。虽然发现的估计误差较小（CV≤7.50%），但对于 2 点 30%-60%，特别是在中心区域，误差较小且偏差较小（SEM≤2.01cm2；偏差≤0.89cm2）。同样，重复性分析显示，2 点 30%-60%的测试-重测误差较小（CV≤1.9%），而 2 点 20%-70%的测试-重测误差较大（CV≤4.6%）。
两点法，特别是使用 30%和 60%区域的两点法，是一种准确且可重复的评估 QUADACSA 的策略。
