Shoulder instability is the inability to retain the humeral head in the glenoid fossa. The incidence of instability is 8.2 to 23.9 per 100,000 person-years with an estimated prevalence of 1.7%. The most common shoulder instability with a rate of 98% is anterior dislocation, in which the humeral head is displaced anterior to the glenoid. Conservative and surgical treatments of instability are available. There are many controversial issues related to these methods in the literature. For example; an atrophy and functional loss in the infraspinatus after reimplissage, atrophy and loss of proprioception in the muscles around the shoulder after capsular repair, and loss of proprioception after the laterjet procedure have been reported.Therefore, the aim of this study was to compare different surgical stabilization methods in terms of pain, proprioceptive sensation, functional status and muscle activation in recurrent anterior shoulder instability, which is very common in adults.

Shoulder instability is the inability to retain the humeral head in the glenoid fossa. The incidence of instability is 8.2 to 23.9 per 100,000 person-years with an estimated prevalence of 1.7%. The most common shoulder instability with a rate of 98% is anterior dislocation, in which the humeral head is displaced anterior to the glenoid. It is more common in young males. While damage is limited to the capsule and labrum in most instabilities seen in young people, rotator cuff tear is also observed in 89% of those over 40 years of age. Trauma is the main cause of shoulder instability. While 96% of shoulder instabilities develop as a result of a blow to the arm in abduction or external rotation of the shoulder with excessive flexion, approximately 4% occur without trauma. Anterior instability occurs when the shoulder is forced into abduction and external rotation by impact, and posterior instability occurs when the shoulder in slight flexion and adduction is hit. The glenohumeral joint is an unstable joint because the depth and size of the glenoid fossa are not fully compatible with the humerus and as a result, the range of motion is wider compared to other joints in the body. While articular surface congruence, articular version, glenoid labrum, capsule and ligaments constitute static factors in ensuring stability; rotator cuff, biceps tendon, intra-articular negative pressure and muscles that form scapulothoracic movements (Trapezoid, Serratus Anterior, Rhomboids, Latissimus Dorsi) constitute dynamic factors. Insufficiency of one or more of these structures causes instability. Conservative and surgical treatments of instability are available. Conservative treatment includes nonoperative methods. These methods consist of electrophysical agents, heat-light agents, exercise and manual treatment methods and proceed through a certain protocol according to the patient's condition and symptoms. In cases where medical and physical therapies are not sufficient, surgical treatment procedures are initiated.

Reimplisasagge, capsular reconstruction and laterjet methods are commonly used in surgical treatments. Reimplissagge operation, which means "to fill", is an open procedure designed to limit the engagement of Hill-Sachs deformity by passing the infraspinatus into the Hill-Sachs defect. The possibility of loss of internal and external rotation as a result of infraspinatus tendon transfer after reimplissage is a matter of debate. Allografts or autografts are used for capsular reconstruction, which is another surgical method. In the procedure performed with capsular repair and grafts, the capsule is strengthened and stabilization is attempted. The laterjet procedure is an operation in which the coracoid process is transferred to the glenoid rim with a screw.

There are many controversial issues related to these methods in the literature. For example; an atrophy and functional loss in the infraspinatus after reimplissage, atrophy and loss of proprioception in the muscles around the shoulder after capsular repair, and loss of proprioception after the laterjet procedure have been reported. Therefore, the aim of our study was to compare these commonly applied methods in terms of pain, proprioceptive sensation, functional status and muscle activation and the hypothesis of the study was as follows; Hypothesis of the Study: Laterjet, reimplissage and capsular reconstruction surgical procedures in recurrent anterior shoulder instabilities affect pain, proprioceptive sensation, functional status and muscle activation differently.

Inclusion Criteria:

• 18 years of age or older,
• At least 4 months after surgery,
• Not having any diagnosed neurological problem

Exclusion Criteria:

• Having an additional diagnosis that would cast doubt on the assessments (rheumatoid arthritis, cancer, neurological disorders, fibromyalgia, psychiatric disorders, etc.),
• Pregnancy status or suspicion
• Having undergone a different surgery such as a fracture with instability.

The sample of the study will consist of individuals who have undergone surgery in the Department of Orthopedics and Traumatology of Dokuz Eylül University Hospital due to instability diagnosis and who have returned to their activities of daily living. The research groups will consist of 30 patients with at least 10 patients each for 3 different surgical methods. These methods will be compared with each other in terms of pain, proprioceptive sensation, functional status and muscle activation. According to the reviewed studies, the number of individuals to be included in the study was determined as 30 individuals in total, 10 in each group.