Auricular Vagus Nerve Stimulation, a non-invasive method, will be used in the study. Studies have shown that vagus nerve stimulation combined with a large vagal nerve network can have a neuromodulatory effect that will activate some natural protective pathways to improve health. Clinically, vagus nerve stimulation is FDA-approved for epilepsy, treatment-resistant depression, and morbid obesity. Since OSS dysfunction is also involved in the etiology of DO and there is no study on the effectiveness of vagus nerve stimulation in this disease, this study is planned to reveal the effectiveness of auricular vagus nerve stimulation and home exercise program in DO patients.

The shoulder junction is a very dynamic structure that has a wide arc of motion and can move in sagittal, vertical and transverse planes, and provides the connection between the trunk and the upper extremity. Due to this dynamic structure, the shoulder junction is a joint where soft tissue pathologies are common. One of the most common of these pathologies is adhesive capsulitis or frozen shoulder (DO). DO has been defined by different names and with some minor differences in the literature for over 100 years. It has been defined by various names such as adherent obliterative bursitis, adhesive bursitis, periarticular fibrositis, scapulohumeral periarthritis, Duplay periarthritis, adhesive capsulitis. DO was first defined as "scapulohumeral periarthritis" in 1896 by Duplay. In 1934, Codman used the term "frozen shoulder" and suggested that it is seen together with rotator cuff tendinitis. The most widely accepted is the definition made by Neviaser in 1945. It is a disease picture characterized by pain and limitation of movement in the shoulder joint, which is defined as inflammation in the capsule and synovium first, followed by adhesion formations, especially in the axillary fold and the attachment of the capsule to the anatomical neck of the humerus.

Although the exact mechanism of action of vagus nerve stimulation is not known, studies on humans have shown that it affects many areas of the brain at the subcortical and cortical level. A high peripheral sympathetic tone causes regional ischemia, which causes widespread pain. Therapeutic interventions that result in vasodilation (eg, exercise) and appropriate autonomic changes have proven to be effective on pain. The vagus nerve, the "great perfect protector" of the body, encompasses a complex neuro-endocrine-immune network that maintains homeostasis. With reciprocal neural connections to multiple areas of the brain, the vagus nerve serves as a control center that integrates sensitive information and provides appropriate feedback responses. Recent studies show that the vagus nerve is involved in inflammation, mood and pain regulation. All of these can be modulated with vagus nerve stimulation. Vagus nerve stimulation, together with an extensive vagal nerve network, can exert a neuromodulatory effect that will activate some natural protective pathways for health restoration.

Recent preclinical studies show that vagus nerve stimulation is very potent and effective in modulating pain in humans. A medical device allowed the auricular branch of the vagus nerve to be stimulated without any surgery. As a result, it was found that the pain threshold increased and the mechanical pain sensitivity decreased. As a result of the studies, there is a possibility that Frozen Shoulder is a disease that occurs with OSS disorder. Vagus nerve stimulation can be used as an adjunct therapy to correct OSS disorder. Since there is no study in the literature on vagus nerve stimulation in Frozen Shoulder, such a study was considered.

Inclusion Criteria:

• To be in the 18-50 age population, to be diagnosed with Frozen Shoulder by a specialist physician

Exclusion Criteria:

• Patients with neurological deficits, neuropathic disorders, chronic inflammation, other musculoskeletal disorders in the upper extremities, pregnant women, and patients who had additional changes in their current treatment other than vagus nerve stimulation were excluded from the study.