Subacromial Corticosteroid Injection for Impingement Syndrome

Clinical Presentation and Diagnosis

The American College of Radiology suggests that pain during abduction beyond 90° indicates subacromial space narrowing, which is a characteristic of subacromial impingement syndrome 2, 3
Pain with external rotation is characteristic of rotator cuff involvement, according to the American Academy of Physical Medicine and Rehabilitation 4, 5
The American Academy of Family Physicians notes that pain only with movement (not at rest) suggests mechanical impingement rather than inflammatory arthropathy 6
Radiation to the lower arm during abduction is consistent with subacromial pathology, as stated by the American College of Radiology 2

The American College of Radiology recommends that the subacromial bursa and rotator cuff (particularly supraspinatus) are the primary pain generators in impingement syndrome, and should be targeted for corticosteroid injection 2, 3
The Canadian Stroke Best Practice Recommendations explicitly state that subacromial corticosteroid injections should be used when pain is thought to be related to injury or inflammation of the subacromial region (rotator cuff or bursa), which is applicable to all subacromial pathology 1
The American College of Radiology notes that ultrasound guidance may include injection of anesthetic and/or corticosteroid when clinically warranted for bursitis or tendinopathy 2, 3

The American College of Radiology suggests that fluoroscopic or ultrasound guidance improves accuracy of subacromial injections, though blind technique is acceptable in experienced hands 3
The injection should target the subacromial-subdeltoid bursa, not the glenohumeral joint itself, as recommended by the American College of Radiology 2
The American Academy of Physical Medicine and Rehabilitation notes that corticosteroid injection is adjunctive therapy, and the patient still requires rehabilitation focusing on rotator cuff and scapular stabilizer strengthening 4, 5, 7

The International Journal of Stroke recommends ensuring there are no contraindications such as active infection (local or systemic), allergy to corticosteroids or local anesthetics, or complete rotator cuff tear requiring surgical repair before proceeding with subacromial corticosteroid injection 1
The American Academy of Family Physicians suggests relative rest for 48-72 hours, gradual return to activity as pain permits, and physical therapy emphasizing rotator cuff strengthening and scapular stabilization following the subacromial injection 6, 1, 4, 5