The LOD for AS is which of the following?

• A. P-A, I-S
• B. P-A, S-I
• C. P-A, M-L
• D. P-A, L-M

Answer: (B)

For atlas subluxation, the thrust path is designed to move the atlas forward and also adjust its vertical position. The best line of drive combines a posterior-to-anterior vector with a downward (superior-to-inferior) component, so the thrust goes P-A and S-I. This direction helps seat the atlas properly under the occiput and align it with the occipital condyles and axis. Other vectors either go upward, side-to-side, or do not address the forward and vertical misalignment characteristic of this pattern, so they’re not the correct LOD for AS.