This study is to investigate whether combination of ultrasound-guided subdeltoidcorticosteroid injection and physiotherapy is more effective than either treatment alone in treatment of patients with chronic subacromial (or subdeltoid) bursitis (SAB).

Chronic subacromial bursitis (SAB) is a common shoulder disorder characterized by chronic shoulder pain with a painful arc of motion, and/or pain on active or passive motions. The diagnosis of SAB requires confirmation by an infiltration with local anesthetic. Previous study showed that corticosteroid injection is more effective than hyaluronic acid in treatment of chronic SAB, however, some (about 20%) patients were not responsive to corticosteroid injection, and some responsive patients may have recurrence of symptoms. The purpose of this study is to investigate whether combination of corticosteroids SASD injections and physiotherapy is more effective than either treatment alone in chronic SAB.

Inclusion Criteria:

1. shoulder pain for more than 1 month
2. age ≥20 years old
3. painful abduction or internal rotation with a visual analog scale (VAS) pain score ≥4
4. the presence of a painful arc of motion or pain at the middle to terminal range of shoulder abduction or internal rotation with an empty or soft end feel
5. positive shoulder impingement test (Neer test and/or Hawkin test)
6. a reduction in pain of ≥40% on active shoulder abduction or internal rotation at the terminal range after injection of 3ml of 1%lidocain into the SASD bursa under US guidance.

Exclusion Criteria:

1. a history of uncontrolled chronic diseases, e.g., malignant neoplasms, blood dyscrasia, and serious infection
2. previous surgery of the affected shoulder
3. any evidence of a rotator cuff tear or tendinopathy, demonstrated by positive resistive tests andsonographic findings
4. calcification of the rotator cuff, demonstrated by x-ray or sonographic findings
5. the presence of arthritis, such asinflammatory arthritis(e.g., rheumatoid arthritis, seronegativespondyloarthropathy, or crystal-related arthropathy), osteoarthritis, frozen shoulder, subacromial spurs, or deformity of the acromion
6. the presence of instability of the affected shoulder
7. a previous fracture near the shoulder region
8. the presence of cervical radiculopathy or myelopathy
9. having received a corticosteroid or hyaluronic acid subacromial or shoulder joint injection in the past 3 months.