What is the recommended approach for a shoulder corticosteroid (corticosteroid) injection?

Shoulder Corticosteroid Injection Approach

Corticosteroid injections into the shoulder joint can provide significant short-term pain relief for specific shoulder conditions, but evidence supporting their use varies by condition and proper technique is essential for effectiveness. 1, 2

Indications for Shoulder Corticosteroid Injection

• Hemiplegic shoulder pain: Subacromial corticosteroid injections are recommended when pain is related to injury or inflammation of the subacromial region (rotator cuff or bursa) 1
• Glenohumeral osteoarthritis: Evidence is insufficient to recommend for or against corticosteroid injections 1
• Rotator cuff tears: Evidence is inconclusive regarding subacromial injections 1
• Shoulder-hand syndrome/CRPS: Early course of oral corticosteroids (30-50mg daily for 3-5 days with tapering over 1-2 weeks) can reduce swelling and pain 1

Injection Technique

Preparation

1. Verify no contraindications (uncontrolled diabetes, active infection)
2. Obtain informed consent discussing risks including infection, skin atrophy, and transient hyperglycemia
3. Position patient appropriately (seated with arm relaxed)
4. Use strict aseptic technique 2

Injection Approaches

1. Subacromial approach (most common):

   • Entry point: 1-2 cm below the lateral edge of the acromion
   • Direction: Aim medially and slightly upward into the subacromial space
   • Depth: 1-2 cm depending on patient size

2. Glenohumeral approach:

   • Entry point: 2-3 cm below the posterolateral corner of the acromion
   • Direction: Aim anteromedially toward the coracoid process
   • Depth: 2-3 cm depending on patient size

Medication

• Typical mixture: Triamcinolone 40mg with 1% lidocaine (total volume 1ml) 3
• Alternative corticosteroids: Methylprednisolone acetate 40mg or equivalent

Improving Injection Accuracy

Accuracy of steroid placement significantly affects clinical outcomes 4:

• Consider ultrasound guidance, especially for glenohumeral injections 2
• Without guidance, accuracy rates are approximately:
  • 29% for subacromial injections
  • 42% for glenohumeral injections 4

Post-Injection Management

1. Monitor for immediate adverse reactions (5-10 minutes)
2. Advise relative rest for 24-48 hours
3. Monitor patients with diabetes for transient hyperglycemia during days 1-3 post-injection 2
4. Schedule follow-up in 2-4 weeks to assess response

Expected Outcomes and Limitations

• Effects typically last 4-8 weeks 2
• Limited evidence for long-term efficacy 5
• Consider limiting frequency to 3-4 injections per year to minimize potential adverse effects on joint structures 2

Cautions and Contraindications

• Avoid injections for 3 months preceding joint replacement surgery 2
• Use cautiously in patients with:
  • Uncontrolled diabetes
  • Immunocompromised status
  • Skin infection at injection site
  • Coagulopathy

Alternative Approaches

If corticosteroid injections fail or are contraindicated:

• Physical therapy focusing on range of motion and strengthening
• Oral NSAIDs if not contraindicated
• Viscosupplementation (hyaluronic acid) for glenohumeral OA 2
• Consider suprascapular nerve blocks for hemiplegic shoulder pain 1

Remember that the evidence supporting corticosteroid injections varies by condition, and injection accuracy significantly impacts outcomes. Ultrasound guidance improves placement accuracy and should be considered, especially for glenohumeral injections.