# Arm Swing Movements during Walking as an Early Predictor of Multiple Sclerosis Progression
## 4 Discussion
Although it was stated that arm swing was not effective in dual task assessment [17], given the disease progression, it is expected that functional mobility will worsen and arm swing during gait may further affect the gait pattern. This, however, remains to be explored in this population. Future research is required to examine the relationship between deteriorating functional mobility and alterations in arm swing, as well as determine whether these alterations could be used as early markers of deteriorating gait in MS patients. While there was no difference in arm swing between the affected and contralateral sides in healthy people, it was found that people with MS had an asymmetry in shoulder amplitude during the initial assessment. At the second evaluation, the shoulder amplitude asymmetries shifted to asymmetries in the elbow and overall arm swing ranges. These findings are consistent with the asymmetry in arm swing reported in [PERSON]'s patients, even in the early stages of the disease [8]. The finding that the elbow amplitude in the unaffected upper limb was significantly lower compared to the affected side in pwMS suggests that upper extremity movements are compensating for impairments on the affected side during walking. While there was no difference in arm swing between individuals with MS and healthy individuals in the initial evaluation immediately after diagnosis, a decrease in elbow movements on the unaffected side was observed in the second evaluation after just 3 months. This may indicate potential functional loss, even if there is no change in EDSS scores or clinical status. We believe that this result provides evidence for the existence of possible changes that may mark the beginning of functional loss in individuals with MS, which have not yet been clinically demonstrated in the early stages, similar to the situation in which walking and balance losses were not previously reflected in clinical scores in the literature [18; 27]. In addition to the clinical tests conducted during the diagnosis of MS, monitoring motor symptoms is crucial due to the disease's progression characterized by attacks and remissions [29]. Motor signs observed during an attack or worsening of the patient's condition play a significant role in predicting progression. Therefore, the arm swing changes especially at the elbow level, may be an early marker of MS. However, the rate of change in arm swing should be further investigated with regard to the type and prognosis of MS. Based on previous studies, it is known that the arm swing has an important role during gait [6; 30; 31; 32; 33] and that an alternate arm swing can also negatively affect gait. Therefore, it is worth investigating whether changing the arm swing is beneficial for these patients. Upper extremity therapies may help different neurologic patients (i.e., hemiplegic cerebral palsy patients [34; 35], and patients after stroke [36; 37; 38; 39]) to improve their gait balance. Arm swing asymmetries in early-stage MS patients have been scarcely studied. While existing literature suggests that they are generally early markers of Parkinson's disease, there is limited research on their significance in MS. Our initial findings on arm swing during walking in pwMS raise important questions for future research. More research may be conducted to determine whether therapies like arm swing training or other upper limb interventions can affect how people with MS walk or balance. Improved therapeutic approaches targeted at improving mobility and lowering the risk of falls in this population may result from a better understanding of the possible advantages of these interventions. Future research could provide insight on how arm swing asymmetries affect the progression of MS and whether they should be the focus of early treatments.