AS subluxation leg length?

• A. Lengthens
• B. No change
• C. Rotates
• D. Shortens

Answer: (A)

Functional leg-length discrepancy arises from how the pelvis and sacrum align. When the sacrum is subluxated in the anterior–superior direction, the pelvis tilts in a way that the leg on that side appears longer. This is a functional change due to pelvic mechanics, not a true anatomical shortening of the limb. So the effect on leg length is lengthening.

This differs from scenarios where there’s no change (the pelvis is neutral), or where the misalignment would produce rotation without a length change, or where a different pattern (like a posterior–inferior shift) might lead to shortening.