What indicates a positive test result for the Sharp Purser Test?

The Sharp Purser Test is designed to assess the integrity of the transverse ligament and identify potential atlantoaxial instability, particularly in patients who may be at risk due to trauma or underlying conditions like rheumatoid arthritis. A positive result is indicated by the presence of subluxation of the atlas (C1) on the axis (C2) during the test.

When the test is performed, the clinician applies a posterior force to the forehead while stabilizing the C2 spinous process. If the test is positive, it may result in a noticeable translation of the atlas, which can produce symptoms such as a “clunk” or increased neurological symptoms. This finding suggests a failure of the transverse ligament to stabilize the atlantoaxial joint properly, indicating potential instability and risk for neurological impairment.

Recognizing subluxation is critical, as it highlights the need for further evaluation and potential intervention to prevent complications. The other choices do not directly indicate a positive Sharp Purser Test; they reflect alternate signs or symptoms that may not specifically confirm the instability that the test aims to evaluate.