# Arm Swing Movements during Walking as an Early Predictor of Multiple Sclerosis Progression
## 2 Materials and Methods  
This study was designed as a single-center, prospective non-randomized controlled study. The pwMS were evaluated at two distinct time points. The first evaluation took place after their initial stable diagnosis, referred to as the pre-evaluation phase. The second evaluation occurred three months after the pre-evaluation, allowing researchers to assess any changes or progress in the patients' condition over this period. The participants did not undergo any physiotherapy and rehabilitation program during the three-month period. Additionally, healthy controls were included in the study and were evaluated once, providing a benchmark for comparison against the pwMS group. This methodological approach was created to produce thorough data on the course and effects of multiple sclerosis within a brief period, providing insightful information for further studies and therapeutic approaches. MS participants were recruited at the Istanbul Dr. [PERSON] Konuk Training and Research Hospital. Age-matched healthy controls were invited to participate in the study. Inclusion criteria for MS participants were to be diagnosed with MS in the last six months recovered from their symptoms, clinically stable, and able to walk uninterrupted for two minutes. Exclusion criteria were having an acute medical illness in the past six months, any other neurological and psychiatric diseases, or any orthopedic, rheumatologic, or vestibular conditions that affect walking were excluded. Patients who had exacerbations between the first and second evaluations (three months after the first evaluation) were excluded. The researcher asked the participants to walk in the confined space of a medical office which provides basic information about the patient's gait pattern (observationally and from video recording) and biomechanical information from a foot pressure analysis system (FreeMed, Sensor Medica, Guidonia Montecelio). The participants walked barefoot back and forth at their comfortable walking speed for two minutes over a three-meter walkway, which included a foot pressure system positioned in the middle of the path. This setup allowed for the collection of detailed foot pressure data as the participants walked. The foot pressure system was instrumental in capturing various metrics, with a particular focus on gait speed. This method provided a controlled environment to assess and compare the walking dynamics of pwMS and healthy controls. A Panasonic Lumix DMC-FE300 digital camera was used to record a gait video at fifty frames per second at a resolution of \(1280\times 720\) pixels. The researcher fixed the camera laterally on a tripod placed two and a half meters away and one meter above the floor with respect to the participants. As such, a sagittal plane video of the walking was recorded (Figure 1). The arm swing movements during walking were evaluated with free version of Kinovea 2D motion analysis software (Kinovea 0.8.15, GPLv2 license, 2019). It is a reliable method to analyze the upper extremity movements and gait analysis ([PERSON], 2019; [PERSON], 2021). For tracking the segments of the upper limbs during walking, sticker markers were placed in specific anatomical areas (left/right acromions, left/right medial and lateral epicondyles, and left/right distal radius and ulna landmarks) ([PERSON], 2019). The shoulder, elbow, and wrist joints were manually positioned within the Kinovea software to accurately map the participants' upper body movements. Based on the identified joint centers, the upper arm, lower arm, and full arm segments were determined. Detailed analyses were conducted to evaluate the shoulder angle (measured from the shoulder joint marker to the elbow joint marker), the elbow angle (measured from the elbow joint marker to the midpoint of the wrist joint marker), and the overall arm swing angle (measured from the shoulder joint marker to the midpoint of the wrist joint marker) during gait (Figure 2).