Shoulder
Impingement
Evidence: confirmed
Internal Rotation Resistance Stress Test (IRRST) Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Differentiating Internal Impingement from Outlet Impingement.
How to Perform
- Position: Abducted 90°, Externally Rotated 80°.
- Action: Compare strength in External Rotation vs Internal Rotation.
Interpretation of Results
- Internal Impingement: Weakness in Internal Rotation.
- Outlet Impingement: Weakness in External Rotation.
Diagnostic Accuracy
- Sensitivity: 88%
- Specificity: 96%
References
- Magee, D. J. (2021). Orthopedic Physical Assessment.