## 4 Discussion  
To our knowledge, this was the first investigation that evaluated the visibility of the ITB strip, examined its morphology using ultrasound, and tried to find any links between ultrasound features and clinical outcomes. The detectability of the ITB strip using ultrasound imaging was presented and its sonographic appearance was described. This study also demonstrated that effusion around the ITB strip in the ultrasound was negatively correlated with the KOOS-symptons subscale that includes questions regarding knee joint stiffness in various positions, swelling, sensations of clicking and locking, as well as the ability to achieve a full range of motion. This relationship may be considered a negative symptom after a LET procedure indicating irritation or inflammation of the ITB strip and potentially contributing to mechanical symptoms mentioned above [18]. However, other functional scores, such as KOOS-pain, KOOS-ADL, KOOS-sport, IKDC, Lysholm, and WOMAC scores, did not support this indication. Moreover, other correlations between ultrasound features and clinical scores were not provided. Sonographic measurements showed that the average width of ITB strips was 5.0 \(\pm\) 1.6 mm, while their height was 4.6 mm \(\pm\) 1.2 mm and their shape in a short axis was rounded. Essentially, in the [PERSON] technique or its modification, it is recommended to obtain a flat graft with a width of 1 to 1.5 cm [19]. The discrepancy between the sonographic measurement and the intraoperative dimensions of the ITB graft harvested according to the surgical technique may result from the fact that the ITB strip undergoes moderate tension during fixation to the lateral femoral condyle. This tension may lead to a reduction in its width and a more rounded shape. Moreover, changes in its size and shape may also be attributed to spontaneous ligamentization processes similar to those observed during the maturation of ACL grafts [20]. In other LET techniques, the following ITB strip widths are advised: the [PERSON] technique and its modification (Arnold and Coker), 2 cm; and the Ellison technique, 1.5 cm [21]. However, if a thinner or wider LET strip led to better clinical results, then surgical techniques recommending a thinner or wider strip would be preferred, but the literature shows that different LET techniques provide similar functional outcomes and rotational stability [22]. This may partially explain why no correlation between the ITB size and clinical outcomes was demonstrated in this study. Regarding the echogenicity of the ITB strip, our results suggest that a hyperechogenic appearance is physiological, as the majority of cases (87.1%) demonstrated this pattern. In contrast, hypoecheogenicity may indicate an ongoing pathological process. However, this ultrasound feature was not associated with clinical outcome scores. The absence of a power Doppler signal in the ITB strip may be interpreted as a lack of hyperemia, which typically correlates with the absence \begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{3}{c}{**Ultrasound Feature—Location**} \\ \hline  & **At the Level of the** & **Between the Femur** & **At the Level of the** & **At the Level of the** \\  & **Femur** & **and the Tibia** & **Tibia** \\ \hline
**KOOS-pain** & 0.502 & 0.905 & 0.500 \\ \hline
**KOOS-symptons** & 0.222 & 0.300 & 0.134 \\ \hline
**KOOS-ADL** & 0.724 & 0.440 & 0.986 \\ \hline
**KOOS-sport** & 0.443 & 0.716 & 0.623 \\ \hline
**KOOS-quality** & 0.600 & 0.337 & 0.185 \\ \hline
**IKDC** & 0.446 & 0.740 & 0.645 \\ \hline
**Lysholm** & 0.369 & 0.351 & 0.240 \\ \hline
**WOMAC** & 0.369 & 0.968 & 0.550 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Significance levels (\(p\)-values) of correlations between ultrasound features (location of the ITB strip) and clinical scores using the Kruskal–Wallis test. of active inflammation or neovascularization. This is consistent with studies showing that mature tendon or graft tissues exhibit no Doppler activity under normal physiological conditions.