What test is performed to indicate a present Erichsen Sign?

• A. Patient lying supine, lifting the leg
• B. Patient prone, pressure applied towards PSISs
• C. Patient standing, flexing the hips
• D. Patient sitting, rotating the trunk

Answer: (B)

The Erichsen Sign is a test commonly used to assess sacroiliac joint dysfunction, specifically to indicate the presence of sacroiliitis or similar conditions that can cause joint inflammation. The correct choice involves the patient lying in a prone position, where the examiner applies pressure towards the Posterior Superior Iliac Spines (PSISs).

This positioning and method allow the clinician to assess if there is any pain or discomfort generated in the sacroiliac joint area when pressure is applied. In cases where pain occurs, it suggests a pathological condition affecting the sacroiliac joint, aligning with what the Erichsen Sign aims to identify.

Other options do not directly relate to the Erichsen Sign. For instance, having the patient lift their leg while lying supine or flex their hips while standing are more indicative of other assessments of hip function or potentially different lower extremity issues rather than specifically targeting the sacroiliac joint. Similarly, having the patient rotate the trunk while sitting is not a method typically used to elicit signs associated with the sacroiliac joint dysfunction. Thus, the emphasis on pressure application towards the PSISs in a prone position is critical for confirming the presence of the Erichsen Sign.