Spine
Cervical Spine
Evidence: confirmed
Sharp-Purser Test Special Test
Orthopedic Physical Examination & Clinical Assessment Guide
What is it used for?
- Assessing Atlantoaxial Instability (Transverse Ligament rupture).
- Commonly used in Rheumatoid Arthritis or Down Syndrome.
How to Perform
- Position: Patient seated, neck slightly flexed.
- Action: Examiner places one hand on the forehead and the other stabilizing the C2 spinous process.
- Force: Apply a posterior force on the forehead (pushing head back).
Interpretation of Results
- Positive Test: A clunk sensation or relief of symptoms.
- Why: If the ligament is torn, C1 slips forward on flexion. Pushing the head back reduces (relocates) C1, relieving the spinal cord compression.
Diagnostic Accuracy
- Sensitivity: 69-88%
- Specificity: 96%
Clinical Context & Limitations
The Sharp-Purser Test 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 Spine region, combining the Sharp-Purser Test with complementary examination tests significantly improves overall diagnostic confidence.
References
- Magee, D. J. (2021). Orthopedic Physical Assessment.
