禹铭杨  　朱 东　   黄 旭   　谷贵山

摘要： 
Painful arc syndrome of the shoulder refers that a painful arc occurs between 60° and 120° when the patient actively abducts the shoulder, and while outside this range the pain will disappear. When the patient moves from a position on the upper arm down along the same route, the pain will appear again between 120° and 60°. But during passive abduction, the pain is relieved significantly. This track is called “subacromial painful arc”. Chronic repetitive microtrauma occurred to the rotator cuff as the greater tuberosity of the humerus moves under the coracoacromial arch when the shoulder is elevated, which is the basic pathophysiological mechanism responsible for the painful arc syndrome of the shoulder. There are many causes for rotator cuff tears, one of which is the morphological variation of the acromion. The acromial morphology is born, so those factors which are likely to damage the tissues are named as “the congenital and osteal etiological factors” of rotator cuff tears. It means that, if the acromial morphology of the patient is just like that, it can be considered that he or she has those factors by nature. The factors will erode the rotator cuff continuously and the patient will have the disease under external incentive condition. Neer supported that in the central part of the supraspinatus tendon, there is the critical area for degenerative tendonitis and tendon rupture, at times extending to the anterior part of the infraspinatus tendon and the long head of the biceps. The most common cause for the pain is tears appearing in this part. With internal rotation of the shoulder, the functional position in which human upper limbs are often used will be achieved, and then the tissues will be brought more closely to the anterior part of the acromion. Elevation of the arm in both internal rotation and external rotation causes the critical area to pass under the coracoacromial ligament or the 1/3 anterior process of the acromion. However, the existence of so many symptoms at the same time makes the pain forms of the shoulder often complicated and untypical. Through retrieving and studying domestic and foreign literature, and reviewing the mechanism and the specific clinical examination methods of the painful arc syndrome of the shoulder, authors have provided some reference for the clinicians to use this diagnostic method more reasonably.