Muscle Thickness, Trunk Proprioception, and Postural Stability in Rotator Cuff Pathology

The rotator cuff consists of the supraspinatus, infraspinatus, teres minor, and subscapularis muscles and their tendons, which surround and stabilize the shoulder joint. Rotator cuff-related disorders may cause pain, particularly during arm elevation and external rotation, and may limit shoulder movement and daily function. Shoulder function depends not only on the muscles surrounding the shoulder but also on the coordinated transfer of force through the trunk and extremities, known as the kinetic chain. Impairments in trunk muscle function, core stability, proprioception, and balance may therefore negatively affect shoulder mechanics. This study aims to investigate the relationships between latissimus dorsi and abdominal muscle thickness, trunk proprioception, and postural stability in individuals with rotator cuff pathology. The study will also examine whether these measurements differ between individuals with rotator cuff pathology and healthy participants.

Inclusion Criteria: Rotator Cuff Pathology Group * Willing to participate in the study and able to provide written informed consent * Aged 18 years or older * Unilateral shoulder pain lasting for at least 3 months * Right-hand dominance * Diagnosis of rotator cuff pathology Healthy Control Group * Willing to participate in the study and able to provide written informed consent * Aged 18 years or older * Right-hand dominance * No current shoulder pain Exclusion Criteria: * Unwilling or unable to provide written informed consent * Younger than 18 years * History of a chronic orthopedic or neurological condition that may affect shoulder, abdominal, or periscapular muscle function * History of injury or surgery involving the abdominal region * Bilateral shoulder pain or bilateral shoulder pathology * Chronic low back pain * Recent history of lumbar spine injury or surgery * Presence of a comorbid condition that may cause balance impairment * History of neuromuscular disease * History of malignancy * Pregnancy * Receipt of physical therapy or rehabilitation for the shoulder region within the previous 6 months