If edema is located in the middle third of the SI joint, which listing is suggested?

• A. PI
• B. AS
• C. EX
• D. IN

Answer: (C)

Edema distribution on the sacroiliac joint guides which listing pattern fits the irritability and restriction present. In this scheme, each third of the SI joint corresponds to a specific pattern, and the middle third is linked to an externally oriented restriction. When edema is localized to the middle third, it points to the EX listing, indicating the ilium is relatively externally rotated or aligned in a way that matches that pattern. The other patterns fit edema in the anterior or posterior thirds (AS and PI) or the lower third (IN), which is not the case here. So the middle-third edema best aligns with the EX listing.