The popliteal space serves as a functional junction in the shoulder joint. From the upper side it is limited by the process of the shoulder, the coracoacromial ligament, the coracoid process of the scapula and the shoulder-blade joint. From the lower side it is limited by the head of the humerus with a part of the greater cusp. The average distance from the inferior border of the scapular process and the border of the humeral head in the anterior view is 9-10 mm. This space contains the infraspinatus bursa, the rotator cone muscles, and the tendon of the long head of the biceps brachii muscle. Due to the reduction of the space, the structures within the space come into conflict and are compressed. Pain most often occurs in the fourth decade of life in people who perform overhead movements of the upper limb and are associated with activities of daily living, work, or sports (e.g., volleyball, tennis, swimming).