The scapulohumeral rehabilitation group will receive 20 minutes of scapulohumeral exercises in addition to the 10-minute neurorehabilitation program. Scapulohumeral Exercises: Scapular mobilization, scapular retraction, protraction, elevation in the scapular plane and Proprioceptive Neuromuscular Facilitation (PNF) exercises with the repeated contractions method. The exercises will be applied according to the functional capacities of the individuals in the supine, sitting and standing positions with 10 repetitions at the beginning, without weights, using free weights and resistance bands, and the number of repetitions and sets will be progressed every week. The intervention groups will receive a total of 21 treatment sessions, 3 days a week for 7 weeks.

In addition to the 10-minute neurorehabilitation program, a 20-minute upper extremity neurorehabilitation exercises and a total of 30 minutes of physiotherapy and rehabilitation program will be applied. Scapular retraction, protraction, elevation movements will be performed in the form of Wand exercises with the help of a stick or cane. Exercises will be progressed by increasing the number of repetitions and sets in supine, sitting and standing positions according to the functional level of the participants. The intervention groups will receive a total of 21 treatment sessions, 3 days a week for 7 weeks.

The control group will consist of healthy volunteers of the same age and gender as individuals diagnosed with Parkinson's disease (PD). The control group will not receive any physiotherapy or rehabilitation program and will only receive relevant assessments to compare with the results of individuals with PD.

It is reported in the literature that scapulohumeral rehabilitation applied in primary shoulder pathologies is effective. In neurological diseases, a study was found in which scapulohumeral rehabilitation was applied to individuals diagnosed with stroke and reported that it was effective. However, when the literature was examined, no study was found in which scapulohumeral rehabilitation was applied to individuals diagnosed with PD. Therefore, our aim is to compare the effectiveness of the scapulohumeral rehabilitation program to be applied for shoulder dysfunction, which is thought to be one of the early findings in PD and is reported to be related to other main findings in PD, with the upper extremity neurorehabilitation program.

It is calculated with the formula (distance between sternal notch - coracoid process / posterolateral angle of acromion - horizontal distance between thoracic spine) x 100.

It is calculated with the formula Pectoralis Minor Index = (Pectoralis Minor Length / Participant's height) x 100.

In the Lateral Scapular Slide Test, the distance to the thoracic spinous process corresponding to the inferior angle of the scapula is measured in three different positions: arms relaxed at the sides, hands on the iliac crest, and arm in 90-degree shoulder abduction and full internal rotation. The distances between the two sides are compared. A difference of more than 1.5 cm between the two sides is considered asymmetric.

150 small wooden cubes are filled from the box where the patient's hand is to be tested to the box next to it. The patient is asked to throw one cube at a time into the empty box next to it. The number of cubes thrown in 60 seconds is counted. The result gives the score. The test is repeated for both hands.

It is a scale developed by Stratford et al. in 2001 and consists of twenty activity questions. The person scores between 0-4 according to the difficulty of doing the activity. The lowest score in total is 0, the highest score is 80. Low scores indicate that the person has difficulty doing the activity due to the condition of the upper extremity.

VAS is a 10-centimeter (cm) scale where 0 is defined as "no pain" and 10 is defined as "unbearable pain". It is a valid and reliable method for assessing the severity of musculoskeletal pain and is frequently used in clinical studies. In a study conducted on patients with chronic musculoskeletal pain, VAS values less than 3.4 cm were classified as mild pain, VAS values between 3.5 and 7.4 cm were classified as moderate pain, and VAS values greater than 7.5 cm were classified as severe pain. The participants' pain severity will be assessed with VAS for resting and activity conditions.