What is the special test for a suspected supraspinatus injury?

Special Tests for Supraspinatus Injury

The "champagne toast" position (30° abduction, mild external rotation, 30° flexion) is the most effective special test for isolating supraspinatus activity and diagnosing supraspinatus injuries, as it provides a significantly better supraspinatus-to-deltoid ratio than traditional tests. 1

Traditional Tests and Their Limitations

Empty Can Test (Jobe Test)

• Performed with the shoulder at 90° abduction, full internal rotation, and 30° forward flexion
• Traditionally considered the standard test for supraspinatus evaluation
• Major limitation: Does not selectively activate supraspinatus 2, 3
• Has nearly the smallest supraspinatus-to-deltoid ratio (0.8) 1
• Activates multiple other shoulder muscles including:
  • Middle deltoid
  • Infraspinatus
  • Anterior deltoid 2, 3

Full Can Test

• Similar to Empty Can but with the thumb pointing upward (external rotation)
• Also fails to selectively activate supraspinatus 3
• Activates 8 other shoulder muscles at similar levels as supraspinatus 3

Superior Alternative: The Champagne Toast Position

Technique

• Position the arm at 30° of abduction
• Add 30° of horizontal flexion
• Maintain mild external rotation
• Elbow flexed to 90° (like holding a champagne glass)
• Apply resistance against abduction

Evidence-Based Advantages

• Highest supraspinatus-to-deltoid ratio (4.6 ± 3.4) 1
• Significantly better isolation of supraspinatus activity compared to Jobe's test 1
• Research shows that lower degrees of abduction combined with external rotation significantly increase the supraspinatus-to-deltoid ratio 4

Clinical Application Algorithm

1. Position the patient correctly:

   • Standing or sitting with arm at 30° abduction
   • 30° horizontal flexion
   • Mild external rotation
   • Elbow flexed to 90°

2. Apply resistance:

   • Apply downward resistance against the patient's attempt to abduct
   • Compare strength bilaterally

3. Interpret findings:

   • Pain during resistance suggests supraspinatus pathology
   • Weakness compared to contralateral side indicates possible tear or dysfunction

Diagnostic Considerations

When to Consider Advanced Imaging

• Persistent pain and weakness despite conservative management
• Suspected full-thickness tear requiring surgical intervention
• MRI without contrast is usually appropriate for suspected rotator cuff tears 5
• Ultrasound can be an alternative with high sensitivity for full-thickness tears 5

Common Pitfalls to Avoid

• Relying solely on the Empty Can test despite its poor specificity
• Failing to compare with the unaffected side
• Not controlling for compensatory muscle activation
• Overlooking the importance of proper patient positioning during testing

The champagne toast position represents a significant improvement over traditional testing methods by better isolating supraspinatus activity, which improves diagnostic accuracy for supraspinatus injuries in clinical practice.