AC Shear Test (Paxinos Sign) Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Diagnosing Acromioclavicular (AC) Joint pathology.
How to Perform
- Position: Patient seated.
- Action: Examiner cups hands over the shoulder: one hand on the clavicle, the other on the spine of the scapula.
- Force: Squeeze the hands together (shearing the AC joint).
Interpretation of Results
- Positive Test: Pain localized at the AC joint.
Diagnostic Accuracy
- Sensitivity: 79%
- Specificity: 50%
Clinical Context & Limitations
The AC Shear Test (Paxinos Sign) should be considered as one component of a comprehensive musculoskeletal assessment. No single special test has perfect diagnostic accuracy; thus, clinical decision-making should integrate test results with patient-reported symptoms, mechanism of injury, functional impairment, and relevant imaging.
Clinicians should be aware of potential false-positive results in patients with pain sensitisation, muscle guarding, or poor relaxation. For the Shoulder region, combining the AC Shear Test (Paxinos Sign) with complementary examination tests significantly improves overall diagnostic confidence.
References
- Magee, D. J. (2021). Orthopedic Physical Assessment.