## 3 Results
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & \multicolumn{2}{c}{**MAR Group (_n = 6_)**} & \multicolumn{2}{c}{**HE Group (_n = 6_)**} & \multicolumn{1}{c}{_p-Value_} \\ \hline Age & 70.3 \(\pm\) 2.8 & 70.2 \(\pm\) 5.7 & 0.95 \\ \hline Body mass index & 26.9 \(\pm\) 2.6 & 28.6 \(\pm\) 4.3 & 0.52 \\ \hline Sex & & & \\ \hline male & 3 (50.0\%) & 2 (33.3\%) & \\ \hline female & 3 (50.0\%) & 4 (66.7\%) & 1 \\ \hline Education & & & \\ \hline Elementary & 5 (83.3\%) & 3 (50.0\%) & \\ \hline Senior high & 1 (16.7\%) & 2 (33.3\%) & 0.22 \\ \hline Bachelor degree and higher & 0 (0.0\%) & 1 (16.7\%) & \\ \hline \hline \multicolumn{3}{c}{Operated side} \\ \hline left & 2 (33.3\%) & 4 (66.7\%) & \\ \hline right & 4 (66.7\%) & 2 (33.3\%) & \\ \hline \hline \multicolumn{3}{c}{Baseline condition (before intervention)} \\ \hline Maximal knee extension (\({}^{\circ}\)) & 28.2 \(\pm\) 8.6 & 24 \(\pm\) 13.7 & 0.40 \\ \hline Maximal knee flexion (\({}^{\circ}\)) & 98.2 \(\pm\) 9.6 & 93.5 \(\pm\) 8.8 & 0.62 \\ \hline VAS & 3.7 \(\pm\) 1.2 & 5.2 \(\pm\) 1.7 & 0.11 \\ \hline WOMAC & 36.5 \(\pm\) 15.5 & 41.7 \(\pm\) 15.7 & 0.58 \\ \hline STSST & & & \\ \hline Total time spending (s) & 22.2 \(\pm\) 9.2 & 27.1 \(\pm\) 11.7 & 0.42 \\ \hline Maximal angular velocity (\({}^{\circ}\)/s) & 100.5 \(\pm\) 35.4 & 94.5 \(\pm\) 35.6 & 0.78 \\ \hline Average angular velocity (\({}^{\circ}\)/s) & 45.5 \(\pm\) 14.4 & 31.5 \(\pm\) 1 \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Dependent Variables**} & \multicolumn{6}{c}{**B(SE)**} \\ \cline{2-9}  & \multicolumn{3}{c}{**(Reference: Baseline)**} & \multicolumn{3}{c}{**(Reference: HE Group)**} \\ \cline{2-9}  & **1-Month Follow-Up** & _p_-Value & **2-Month Follow-Up** & _p_-Value & **Group at 1-Month** & _p_-Value & **Group at 2-Months** & _p_-Value \\ \hline Maximal knee extension (\({}^{\circ}\)) & \(-6.6\) (3.4) & \(0.0497\) & \(-8.1\) (4.0) & \(0.043\) & \(-8.5\) (4.5) & \(0.057\) & \(-10.7\) (5.4) & \(0.049\) \\ \hline Maximal knee flexion (\({}^{\circ}\)) & \(8.2\) (1.9) & \(0.000\) & \(11.3\) (3.1) & \(0.497\) & \(4.5\) (5.3) & \(0.397\) & \(3.2\) (4.7) & \(0.499\) \\ \hline VAS & \(-1.8\) (0.6) & \(0.002\) & \(-3.0\) (0.5) & \(0.000\) & \(1.5\) (0.7) & \(0.450\) & \(1.7\) (1.0) & \(0.083\) \\ \hline WOMAC & \(-16.0\) (1.6) & \(0.000\) & \(-24.8\) (2.9) & \(0.000\) & \(-2.7\) (4.0) & \(0.510\) & \(-2.7\) (5.3) & \(0.617\) \\ \hline
5 TSST & & & & & & & \\ \hline Total time (s) & \(-6.2\) (1.5) & \(0.000\) & \(-8.9\) (1.9) & \(0.000\) & \(-1.9\) (2.3) & \(0.413\) & \(-2.6\) (2.4) & \(0.279\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Generalized estimating equation analysis for improvements between groups. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Baseline**} & \multicolumn{3}{c}{**\(\mathbf{1 Month}\)**} & \multicolumn{3}{c}{_\(\boldsymbol{p\text{-Value}}\)**} & \multicolumn{3}{c}{_\(\boldsymbol{p\text{-Value}}\)**} \\ \cline{2-9}  & **1-Month Follow-Up** & **Versus Baseline** & **Between Groups a** & **Follow-Up** & **Versus Baseline** & **Between Groups b** \\ \hline \multicolumn{9}{c}{MAR group (\(n=6\))} \\ \hline Maximal knee extension (\({}^{\circ}\)) & \(28.2\) \(\pm\) \(8.6\) & \(13.0\) \(\pm\) \(5.8\) & \(0.03\) & \(0.17\) & \(9.3\) \(\pm\) \(5.2\) & \(0.03\) & \(0.04\) \\ \hline Maximal knee flexion (\({}^{\circ}\)  
The mean scores of the participants in the MAR group for the user experience related items of device helpfulness, ease of operability, satisfaction with app design, and interest in future use were 8.5 \(\pm\) 1.0 (range: 7-10), 5.0 \(\pm\) 1.4 (range: 3-7), 7.7 \(\pm\) 0.8 (range: 7-9), and 5.8 \(\pm\) 1.9 (range: 3-8), respectively. Participants' feedback for the overall MSD design is summarized in Table 6.