It has been proposed that altered scapular muscle function can contribute to alterations in shoulder kinematics, which often lead to SD and are frequently associated with other shoulder pathologies, such as RC tears, labrum tears, impingement syndrome, and glenohumeral joint instability. However, whether SD leads to the development of these diseases or is a consequence has yet to be clarified. Changes in scapular kinematics can be attributed not only to altered scapular recruitment patterns (e.g., altered serratus anterior muscle activity) or muscle performance (e.g., force imbalance in the upper and lower trapezius muscles) but also to flexibility deficits in the soft tissue surrounding the scapula, which may restrict normal scapular movement during daily activities and sport- specific movements. Although many studies have investigated the optimal management method, to date, there is no consensus. Conservative approaches involve not only physiotherapy but also other techniques, such as extracorporeal shockwave therapy.