Effect of Transcutaneous Auricular Vagus Nerve Stimulation Combined With Upper Extremity Robot-Assisted Training on Upper Extremity Motor Functions in Stroke Patients

We will use the Fugl-Meyer Upper Motor Assessment score, which is the most sensitive for treatment outcomes in stroke patients presenting with unilateral paresis in the post-stroke period. It measures upper extremity use and impairment, measuring shoulder, elbow, forearm, wrist, finger, and reflex movements from proximal to distal, synergistic to extrinsic. The score ranges from 0 to 66 and consists of 33 items. 0-28 indicates severe motor impairment; 29-42 indicates moderate motor impairment; and 43-66 indicates mild motor impairment. Higher scores indicate better performance. The FM-UE consists of one component, each rated on a 3-point ordinal scale (0=not achieved, 1=partially contributed, 2=completely contributed). The minimum clinically meaningful change on the FM-UE for chronic stroke has been determined to be 4.25 to 7.25. Consistent with the literature, we define an improvement of at least 6 points or more as significant.

The Box and Block Test is a manual dexterity test used to assess upper extremity motor function. It primarily assesses gross motor function. It is calculated by the number of 2.5 cm3 blocks thrown from one side to the other in 1 minute. A box and block test kit has been prepared to meet international standards.

Grip strength on the affected side will be measured with a Jamar Hydraulic Dynamometer. The measurement protocol will be explained and demonstrated to the participant by an experienced physiotherapist. The dynamometer grip size will be adjusted to the participant's hand size, and the participant will be asked to squeeze the dynamometer for a practice trial. Anti-gravity support will be provided to maintain the position if necessary. Grip strength measurements with the Jamar dynamometer have proven to be highly valid and reliable, and normative values have been published.

The SIS 3.0 assesses function and quality of life based on subjective report in eight clinically important domains. It consists of two parts. The first part is the main scale of the IAS, which assesses multidimensional health-related quality of life (QOL) including strength, hand function, ADL/instrumental ADL, mobility, communication, emotion, memory/thinking, and social participation. It consists of 59 items, and each item is subjectively rated by stroke patients on a 5-point Likert-type scale according to their perceived difficulty with the item in the past week. The score for each domain is converted to a score out of 100, and the average scores for all domains are used to represent stroke patients' multidimensional health-related quality of life. The formula Domain Score = [(Average Item Score -1) / (5 -1) x 100] is used to convert each domain score. SIS 3.0 also includes assessment of post-stroke recovery using a 0-100 visual analog scale (0: no recovery, 100: complete recovery)