Acromial Bursa Inflammation

　　1. Etiology

　　It can be caused by direct or indirect trauma, injury or degenerative changes of the supraspinatus tendon, long-term compression and stimulation.

　　2. Pathogenesis

　　Subacromial bursa, also known as the subdeltoid bursa, is divided into two parts: subacromial and subdeltoid. There may be a thin septum between them, but most are interconnected. The bursa separates the greater tubercle of the humerus from the deltoid muscle and the acromion process, preventing the greater tubercle from rubbing against the acromion underneath.

　　Subacromial bursitis, which can be caused by direct or indirect trauma, but most cases are secondary to injury and degenerative changes of the surrounding tissues of the shoulder joint, especially the injury, degeneration, and calcification of the supraspinatus tendon at the bottom of the bursa. Due to damage or long-term compression, friction, and other mechanical stimulation, the bursal wall may develop congestion, edema, exudation, proliferation, hypertrophy, and adhesion, leading to sterile inflammatory reactions.

　　Severe cases may be accompanied by fibrous ankylosis of the shoulder joint. Due to the empty joint cavity, absence of the humeral head, prominent acromion, it forms a typical square shoulder deformity. The presence of square shoulder deformity is seen in shoulder joint tuberculosis. Shoulder joint tuberculosis is relatively rare, accounting for only 1.06% of all bone and joint tuberculosis. It is more common in adults than in children (Turek, 1977), with the highest incidence between 21-30 years old. Most cases occur in young and middle-aged adults, and patients often have active pulmonary tuberculosis. Males are slightly more than females. The left side is slightly more common than the right.

　　1. General symptoms

　　Pain, limited range of motion, and localized tenderness are the main symptoms of subacromial bursitis. The pain gradually worsens, with more severe pain at night. Pain increases during movement, especially during abduction and external rotation (compressing the bursa). The pain is usually located deep in the shoulder, involving the insertion points of the deltoid muscle, and can also radiate to the scapular, neck, and hand areas.

　　2. Local symptoms

　　Examination reveals tender points at the shoulder joint, under the acromion, and at the greater tubercle, which can move with the rotation of the humerus. When the bursa swells and accumulates fluid, there is tenderness over the entire shoulder joint area and deltoid region. To alleviate pain, patients often keep the shoulder joint in adduction and internal rotation to reduce the compression and irritation on the bursa. With the thickening and adhesion of the bursal wall, the range of motion of the shoulder joint gradually decreases and may eventually disappear. In the late stage, atrophy of the scapular band muscles can be seen.

　　It can be caused by direct or indirect trauma, injury to the supraspinatus tendon or degenerative changes, long-term compression and stimulation. Such as a fall, a fall, or a direct cause of an emergency brake while driving. Therefore, pay attention to living habits, high-risk workers such as construction workers, miners, and machine operators are prone to injury, and pay attention to protecting themselves during the work process. Stay calm when dealing with things, avoid emotional excitement leading to conflict and causing the disease. Secondly, early discovery, early diagnosis, and early treatment are also of great significance for the prevention of the disease.

　　1. Tenderness

　　There is marked localized tenderness at the lateral side of the shoulder joint and under the acromion and greater tubercle.

　　2. Swelling

　　During the acute phase, due to the congestion and edema of the bursa, a swollen bursa can be felt in front of the shoulder joint. In the chronic phase, patients can feel different-sized nodular positive objects on the lateral side of the acromion.

　　3. Dysfunction

　　Dysfunction during the acute phase is often caused by pain, and dysfunction during the chronic phase is often caused by the gradual inflammation and thickening of the bursal wall and adhesion to the tendon sheath. Especially in abduction and external rotation.

　　4. Muscle atrophy

　　Early onset of upper muscle and infraspinatus muscle atrophy, late onset of deltoid muscle atrophy.

　　5. X-ray examination

　　Early shoulder joint is mostly negative, and late stage can see calcium salt deposition in the supraspinatus tendon.

　　The diet of patients with subacromial bursitis should be light and easy to digest, eat more vegetables and fruits, rationally match the diet, and pay attention to sufficient nutrition. In addition, patients should also pay attention to avoiding spicy, greasy, and cold foods..

　　1. Treatment

　　Firstly, find out the primary disease cause and give targeted treatment. The treatment during the acute phase includes rest, administration of anti-inflammatory and analgesic drugs, physical therapy, acupuncture, and placing the affected limb in abduction and external rotation position. Local injection of corticosteroid hormones has a good effect. In the chronic phase, in addition to the above therapies, emphasize rehabilitation treatment that does not increase pain, mainly to restore the shoulder joint's movement function on three axes. For those who are ineffective after conservative treatment, consider surgical treatment, including capsular resection, calcification removal of the supraspinatus tendon, resection of the acromion and coracoid ligament, and other shaping surgeries.

　　2. Prognosis

　　Generally, the prognosis is good after treatment.