# Arm Swing Movements during Walking as an Early Predictor of Multiple Sclerosis Progression
## 4 Discussion  
In this study, we aimed to reveal the changes in arm swing during walking following a short period after diagnosis in early MS, and it was found that the elbow ROM value on the least affected side was lower in pwMS than in healthy controls. The novel aspect of this study lies in its detailed description of the changes in arm swing among pwMS during the early stages of the disease. Previous research has predominantly focused on other motor symptoms or on more advanced stages of MS, leaving a gap in our understanding of how these early changes in arm swing might signal the onset and progression of the disease. By concentrating on this specific aspect, our study aimed to reveal the changes in arm swing during walking even in a short period after diagnosis in early MS. Understanding these changes in arm swing could provide valuable insights into the broader spectrum of motor function deterioration in pwMS, ultimately contributing to better patient outcomes through timely and targeted therapeutic approaches. Even though the arm swing movements during walking were similar between early MS patients and healthy controls, asymmetry between the most and least affected side was evident in early MS patients and not in healthy controls. Additionally, after short period from diagnosis, the elbow amplitude was decreased on the least affected side in pwMS compared to healthy controls which corroborates results from a previous study in pwMS [15]. According to that study, patients with low EDSS scores may experience alterations in gait and arm swing due to the condition. However, in their study involving pwMS with low EDSS scores, the authors reported a reduced walking speed, which was confirmed by other researchers [27]. As such, [PERSON] et al. [15] indicated that, in their sample of low EDSS pwMS, the decrease in elbow amplitude may be connected to walking speed. In the current study, on the other hand, any differences were detected in walking speed between our sample of early MS patients with low EDSS and healthy controls. This suggests that the presented arm swing pattern is a direct effect of the MS \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Healthy Controls** & **pwMS First Evaluation** & **pwMS Second Evaluation** & **Between Groups §** \\  & **(Group 1)** & **(Group 2)** & **(Group 3)** & & \\ \hline Walking speed & & & & & \\ (mm/s) & 462.5 \(\pm\) 17.5 & 495.2 \(\pm\) 62.2 & 456.6 \(\pm\) 54.8 & 0.125 (2 vs. 3) (r = 0.31, d = 0.65) & \\  & & & & 0.130 (1 vs. 3) (r = 0.35, d = 0.61) & \\ \hline
2 MWT (m) & - & 207.0 \(\pm\) 15.7 & 195.8 \(\pm\) 50.3 & 0.367 (r = 0.14, d = 0.30) & \\ \hline TUG (s) & - & 6.0 \(\pm\) 0.7 & 5.8 \(\pm\) 0.5 & 0.196 (r = 0.16, d = 0.32) & \\ \hline T25 FW (s) & - & 4.8 \(\pm\) 0.6 & 4.6 \(\pm\) 0.4 & 0.139 (r = 0.19, d = 0.39) & \\ \hline \hline \end{tabular} Abbreviations: pwMS, people with Multiple Sclerosis; SD, standard deviation; mm, millimeter; sec, second; 2 MWT, two-minute walk test; m, meter; TUG, timed up and go; T25 FW, timed 25-foot walk test. \(r_{i}\) effect size value, d; Cohen’s d value.  
\end{table} 
Table 3: Comparison of the functional parameters between groups. rather than being a gait compensation. Walking speed, which is one of the main factors affecting arm swing during walking [28], was found to be similar both between the groups and between the first and second assessments. Therefore, decreased elbow amplitude and increased arm swing asymmetry without any change in walking speed may be associated with disease progression in individuals with MS, especially in the early period. In this study, the results of functional tests repeated at 3-month intervals showed no functional deterioration. However, this may be due to a wide variety of factors affecting functional mobility. Since patients were included early in their diagnosis, they had low initial EDSS scores. As a result, functional mobility was only mildly affected, which may have hindered the detection of a relationship with arm swing parameters in MS.