Sharp-Purser Test Special Test

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%

References

• Magee, D. J. (2021). Orthopedic Physical Assessment.