Subacromial bursitis, also known as deltoid bursitis, is mostly secondary to lesions in adjacent tissues, such as shoulder muscle strains and supraspinatus tendinitis.

bubble_chart Etiology

When the shoulder suffers a direct impact or excessive abduction, it can lead to acute subacromial bursitis. Since the supraspinatus tendon lies at the base of the subacromial bursa, chronic strain or degeneration of the supraspinatus tendon inevitably affects the subacromial bursa as well. Therefore, when there is a lesion in the subacromial bursa, it often indicates an underlying condition in the supraspinatus tendon.

bubble_chart Clinical Manifestations

In acute onset, there is widespread pain in the shoulder, restricted joint movement, and increased pain during activity. The pain is located deep in the shoulder and often radiates to the insertion of the deltoid muscle. Tenderness is evident in the anterior part of the shoulder joint, and a swollen bursa may be palpable. In chronic cases, the pain is less pronounced, with the tender point located at the insertion of the deltoid muscle. Pain worsens during shoulder abduction and internal rotation, with tenderness over the greater tubercle of the humerus, lateral to the acromion. When the shoulder is abducted and the greater tubercle moves beneath the acromion, the tender point becomes less noticeable.

Diagnosis and differentiation:

1. In acute onset, there is widespread pain in the shoulder, restricted joint movement, and increased pain during activity. The pain is located deep in the shoulder and often radiates to the insertion of the deltoid muscle. Tenderness is evident in the anterior part of the shoulder joint, and a swollen bursa may be palpable. In chronic cases, the pain is less pronounced, with the tender point located at the insertion of the deltoid muscle. Pain worsens during shoulder abduction and internal rotation, with tenderness over the greater tubercle of the humerus, lateral to the acromion. When the shoulder is abducted and the greater tubercle moves beneath the acromion, the tender point becomes less noticeable.
2. X-ray examinations are often negative, but in cases of calcific bursitis, calcifications may be visible.

bubble_chart Treatment Measures

1. The main treatment principles are pain relief, prevention of bursa adhesion, and restoration of shoulder joint function. During the acute phase, the forearm should be immobilized with a sling, or a brace can be used to maintain the shoulder joint in a 90° abduction position. Local heat therapy, physiotherapy, tuina, etc., can be applied. Hydrocortisone acetate with procaine can be injected into the bursa. For chronic bursitis, while undergoing physiotherapy and medication, gradually increase the range of motion to restore joint function.
2. For refractory pain in subdeltoid bursitis, if non-surgical therapy is ineffective, surgical removal of the bursa may be considered. However, in cases of old and complete rotator cuff tears, repair surgery is often ineffective. When severe thickening of the bursa significantly impairs shoulder abduction, acromionectomy may be performed.