## 3 Results
Even though such a small difference is questionable from a clinical point of view, generally, the vGRF BM values obtained in the involved and uninvolved limbs in this group of patients were lower than in the patients with longer physiotherapy supervision duration and in the control group. Association of Vertical Ground Reaction Force Normalized to Body Mass (vGRF BM) Limb Symmetry Index and Postoperative Physiotherapy Supervision Duration  
The vGRF BM LSI during the double-leg vertical hop landing was highly (\(r\) = 0.727; \(p\) < 0.001) associated with the postoperative physiotherapy supervision duration (Figure 6). The longer the postoperative physiotherapy supervision duration, the higher the LSI value, indicating a better result. The 53% of the total variation in vGRF BM LSI during double-leg vertical hop landing can be explained by the positive linear relationship between the vGRF BM LSI during the double-leg vertical hop landing and the postoperative physiotherapy supervision duration (\(r^{2}\) = 0.529). There was also a significant positive correlation between the vGRF [BMI] LSI during the single-leg vertical hop landing and postoperative physiotherapy supervision duration (Figure 7), but its level was low (\(r\) = 0.333; \(p\) = 0.041). Only 11% of the total variation in vGRF BM LSI during the single-leg vertical hop landing can be explained by the positive linear relationship between vGRF BM LSI during single-leg vertical hop landing and postoperative physiotherapy supervision duration (\(r^{2}\) = 0.111). The other 89% of the total variation remains unexplained. Additionally, we analyzed the correlation of the time between the ACL injury and ACLR with the vGRF [BMI] LSI value during the vertical double-leg hop landing (\(r\) = 0.081; \(p\) = 0.628) and the correlation of this time with the vGRF [BMI] LSI value during the vertical single-leg hop landing (\(r\) = 0.130; \(p\) = 0.438). There was no association between those studied features. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{4}{c}{**Vertical Hop Landing vGRF BM Limb Symmetry Index**} \\ \hline \hline \multicolumn{4}{c}{**ACL-Reconstructed Patients**} \\ \hline \hline \multirow{2}{*}{**Total Number**} & **Physiotherapy Supervision \textless{}6 Months** & **Physiotherapy Supervision \textgreater{}6 Months** & **Control Group** & \(p\) \\ \hline \multirow{2}{*}{92.52 (89.39, 95.64)} & **Double-leg** & \multirow{2}{*}{99.05 (96.94, 101.16)} & \multirow{2}{*}{99.34 (95.28, 103.39)} & \multirow{2}{*}{\(\leq\)0.001 1  } & **Double-leg** & \multirow{2}{*}{99.05 (96.94, 101.16)} & \multirow{2}{*}{99.34 (95.28, 103.39)} & \multirow{2}{*}{\(\leq\)0.001  } & **Single-leg** & \multirow{2}{*}{96.97 (94.38, 99.57)} & \multirow{2}{*}{94.03 (89.66, 98.39)} & \multirow{2}{*}{101.44 (99.21, 103.68)} & \multirow{2}{*}{0.003 2  } \\  & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Between-group comparison of vertical ground reaction force limb symmetry index values obtained during double-leg and single-leg vertical hop landing in patients with postoperative physiotherapy supervision \textless{}6 months, patients with postoperative physiotherapy supervision \textgreater{}6 months, and the control group; ACL: anterior cruciate ligament; \(p\): level of significance of the between-group difference; vGRF BM: vertical ground reaction force normalized to body mass. Values expressed as the arithmetic mean and 95% confidence interval.