Conventional exercises will be applied.

In addition to the conventional exercises, Instrument-Assisted Soft Tissue Mobilization (IASTM) will be applied.

All participants will receive a standardized electrotherapy program in a clinical setting, consisting of TENS (100 Hz, 30 minutes), ultrasound (1.5 W/cm², 8 minutes), and a 15-minute cold-pack application, delivered three times per week for four weeks. In addition to electrotherapy, participants in the conventional exercise group will perform a physiotherapist-guided exercise program aimed at improving shoulder flexion, abduction, internal and external rotation through stretching and range-of-motion exercises. The program will include Codman exercises, wand exercises, finger-ladder activities, and condition-appropriate strengthening exercises, progressed according to each participant's pain level and tolerance.

The Visual Analog Scale (VAS) is a tool used to measure pain intensity as a single-dimensional construct across different adult populations. It typically consists of a horizontal or vertical line measuring 10 cm in length. On this scale, a score of 0 indicates no pain, while a score of 10 represents the worst pain imaginable.

Shoulder flexion, abduction, internal rotation, and external rotation range of motion will be assessed using a universal goniometer while the patient is positioned in supine and performs the movements actively.

The Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire is a scale that evaluates functional status and capability following injuries or disorders affecting the upper extremity. The DASH consists of 30 items. These items assess difficulties encountered during specific tasks, as well as pain, numbness, stiffness, weakness, sleep problems, self-confidence, and participation in social activities. Scores range from 0 to 100, with higher scores indicating greater impairment in upper extremity function.

To evaluate shoulder proprioception, joint position sense will be measured at 60° of shoulder flexion and 60° of shoulder abduction. During the assessment, participants will be positioned in standing and guided to the target angles by the physiotherapist using a goniometer. In each position, participants will be asked to maintain 60° of flexion or 60° of abduction for 10 seconds with their eyes open and to memorize the perceived position. They will then be instructed to reproduce the same movement with their eyes closed. The difference between the angle measured with eyes open and the angle reproduced with eyes closed will be recorded as the joint position sense error (error angle).