## 3 Results
### Functional Reach Performance Test
\begin{tabular}{c c c c c c} \hline \hline  & & \multicolumn{3}{c}{**Between Conditions Comparisons**} \\ \cline{3-5}  & & \multicolumn{3}{c}{**Mean (SD)**} & \multicolumn{3}{c}{**F Value (df); \(p\)-Value**} \\
**Variable** & **Condition** & & **(Observed Power)** \\ \cline{3-5}  & & **Reach** & **Return** & **Reach** & **Return** \\ \hline \multirow{3}{*}{AP CoP Displacement (cm)} & Control & 4.11 (2.78) & 4.28 (3.32) & \multirow{3}{*}{1.871 (3); 0.139} & \multirow{3}{*}{1.145 (3); 0.334} \\  & 220 mL & 4.63 (2.90) & 4.69 (3.39) & & (0.472) & (0.300) \\ \cline{3-5}  & 315 mL & 4.15 (2.66) & 4.09 (2.86) & & (0.472) & (0.300) \\ \cline{3-5}  & 365 mL & 4.01 (2.52) & 4.02 (2.91) & & \\ \hline \multirow{3}{*}{ML CoP Displacement (cm)} & Control & 1.91 (0.50) & 1.98 (0.52) & \multirow{3}{*}{3.195 (3); 0.027 *} & \multirow{3}{*}{1.203 (3); 0.313} \\  & 220 mL & 2.08 (0.53) & 2.06 (0.72) & & \\ \cline{3-5}  & 315 mL & 1.84 (0.45) & 1.89 (0.57) & & (0.723) & (0.314) \\ \cline{3-5}  & 365 mL & 1.93 (0.43) & 1.98 (0.75) & & \\ \hline \multirow{3}{*}{AP CoP Mean Velocity (cm/ms)} & Control & 8.44 (9.93) & 9.19 (10.42) & \multirow{3}{*}{0.212 (3); 0.888} & \multirow{3}{*}{0.788 (2.561); 0.486} \\  & 220 mL & 7.53 (9.24) & 8.13 (9.30) & & \\ \cline{3-5}  & 315 mL & 8.04 (8.64) & 8.67 (9.23) & & (0.089) & (0.199) \\ \cline{3-5}  & 365 mL & 8.23 (11.76) & 8.55 (12.00) & & \\ \hline \multirow{3}{*}{ML CoP Mean Velocity (cm/ms)} & Control & 2.69 (1.85) & 2.48 (0.70) & \multirow{3}{*}{1.154 (3); 0.331} & \multirow{3}{*}{1.337 (3); 0.267} \\  & 220 mL & 2.34 (0.71) & 2.46 (0.62) & & \\ \cline{3-5}  & 315 mL & 2.24 (0.73) & 2.39 (0.74) & & (0.303) & (0.347) \\ \cline{3-5}  & 365 mL & 2.31 (0.91) & 2.33 (0.67) & & \\ \hline \hline \end{tabular} 
\begin{tabular}{c c c c c} \hline \hline  & & \multicolumn{3}{c}{**Between Conditions Comparisons**} \\ \cline{3-5}  & & \multicolumn{3}{c}{**F Value (df); \(p\)-Value**} \\
**(Observed Power)** & & & **(Observed Power)** \\ \cline{3-5}  & & \multicolumn{3}{c}{**Reach**} & **Return** & **Reach** & **Return** \\ \hline \multirow{3}{*}{AP CoP Displacement (cm)} & Control & 4.11 (2.78) & 4.28 (3.32) & \multirow{3}{*}{1.871 (3); 0.139} & \multirow{3}{*}{1.145 (3); 0.334} \\  & 220 mL & 4.63 (2.90) & 4.69 (3.39) & & (0.472) & (0.300) \\ \cline{3-5}  & 315 mL & 4.15 (2.66) & 4.09 (2.86) & & (0.472) & (0.300) \\ \cline{3-5}  & 365 mL & 4.01 (2.52) & 4.02 (2.91) & & \\ \hline \multirow{3}{*}{ML CoP Displacement (cm)} & Control & 1.91 (0.50) & 1.98 (0.52) & \multirow{3}{*}{3.195 (3); 0.027 *} & \multirow{3}{*}{1.203 (3); 0.313} \\  & 220 mL & 2.08 (0.53) & 2.06 (0.72) & & 3.195 (3)In both phases, the sEMG activity results showed that the mean between implant conditions was not variable enough to see statistically significant differences in muscle activity of ECM, ESC, PM, LS, LM, and Tra/IO. In the reach phase, pairwise comparisons of UT and LT mean activity levels showed statistical differences between conditions. Specifically, only the 315 mL implant condition showed statistically decreased UT activity and increased LT activity compared to the control condition. Increased LT activity was also seen when comparing the 365 mL implant condition to the control. In the return phase, pairwise comparisons showed that the mean UT activity of the 220 mL implant had a significantly lower mean compared to the control. High within-group standard deviations were found for all muscles, especially those with significant differences (Table 6).