# Applicability of Semi-Quantitative Evaluation of the Intercondylar Notch
## 4 Discussion  
The results presented in this investigation reflect the challenges in the shape evaluation of the IN. The hypothesis was only partially confirmed: shape classification was reproducible and performed reliably only with the introduction of visual assistance. In the scope of risk evaluation and clinical applicability, specific and reliable statements concerning the shape of the IN, and, therefore, the prognosis of ligament degeneration or rupture, may only be made when applying rigid and reliable identification guides. Information on the shape of the IN is important in the assessment of the health of the knee joint, especially when considering risk factors of cruciate ligament rupture or degeneration. As the osseous structures change with age, the shape of the IN changes along with it, rendering it a valuable sign in evaluating risk factors of ligament involvement in the onset and development of osteoarthritis in elderly patients [12; 15; 33; 34; 35]. In addition, the position of the performed NW measurement is of importance. Most often, the NW is measured at the level of the poplilical sulcus [4; 12; 14; 16; 17; 33]. [PERSON] et al. [12] showed that changes to the IN with the development of ligament-endangering ridges, as described by [PERSON] et al. [19; 20], do not occur within the notch but at the level of the osteochondral border, i.e., the joint line [12]. Based on their evaluation of the notch, they identified three shapes (A-shape, inverse U-shape and \(\Omega\)-shape) reflecting the difference between the NW at the level of the poplileal sulcus (within the IN) and that at the level of the joint line (at the osteochondral border). Although these descriptions of shapes exist and a correlation between specific shapes of the IN and the risk of ligament degeneration and ligament rupture has been proven, no effort has been made to prove the reliability of such risk evaluation [4; 12; 14; 16; 17]. [PERSON] et al. [35] found a statistically significant difference between the shape of the IN in patients with osteoarthritis of the knee and patients without it. These differences were \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Shape**} & \multirow{2}{*}{**Control**} & \multicolumn{6}{c}{**SqE**} & \multicolumn{6}{c}{**aSqE**} \\ \cline{2-11}  & & **Total** & **Correct** & & **Mistaken As** & **Total** & **Correct** & & **Mistaken As** & \\ \hline \hline \multirow{2}{*}{A-shape} & \multirow{2}{*}{43} & \multirow{2}{*}{44} & \multirow{2}{*}{25} & \multirow{2}{*}{-} & \multirow{2}{*}{6} & \multirow{2}{*}{12} & \multirow{2}{*}{44} & \multirow{2}{*}{41} & \multirow{2}{*}{0} & \multirow{2}{*}{3} & \multirow{2}{*}{0} \\  & & & & & & & & & & & \\ \hline Inverse & \multirow{2}{*}{100} & \multirow{2}{*}{37} & \multirow{2}{*}{19} & \multirow{2}{*}{12} & \multirow{2}{*}{-} & \multirow{2}{*}{69} & \multirow{2}{*}{103} & \multirow{2}{*}{94} & \multirow{2}{*}{4} & \multirow{2}{*}{0} & \multirow{2}{*}{5} \\ U-shape & & & & & & & & & & & \\ \hline \(\Omega\)-shape & \multirow{2}{*}{187} & \multirow{2}{*}{249} & \multirow{2}{*}{165} & \multirow{2}{*}{6} & \multirow{2}{*}{12} & \multirow{2}{*}{-} & \multirow{2}{*}{183} & \multirow{2}{*}{180} & \multirow{2}{*}{0} & \multirow{2}{*}{3} & \multirow{2}{*}{0} \\ \hline Total & \multirow{2}{*}{330} & \multirow{2}{*}{330} & \multirow{2}{*}{209 \({}^{*}\)} & \multirow{2}{*}{18} & \multirow{2}{*}{81} & \multirow{2}{*}{330} & \multirow{2}{*}{315 \({}^{*}\)} & \multirow{2}{*}{4} & \multirow{2}{*}{6} & \multirow{2}{*}{3} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Comparison of semi-quantitative evaluation (SqE) and assisted semi-quantitative evaluation (aSqE) with calculated control. Note the significant difference between the results of SqE and asqE (*). mostly found at the lateral intercondylar wall of the medial condyle. The non-osteoarthritis showed an overall wave-like shape, and the osteoarthritis patients showed an inverse U-shape. This contradicts the data of [PERSON] et al.