A patient has restricted left rotation at the C5-C6 level. When performing a unilateral posterior-anterior joint mobilization, placement of the physical therapist's hand at which location is MOST likely to increase left rotation?

• A. Left Posterior Articular Pillar at C5
• B. Left Posterior Articular Pillar at C6
• C. Right Posterior Articular Pillar at C5
• D. Right Posterior Articular Pillar at C6

Answer: (C)

When one side’s rotation is limited, think about which facet joint is acting as the block. For left rotation at the C5–C6 segment, the right facet joint is the primary limiter. A unilateral posterior–anterior mobilization applied to that facet — specifically over the right posterior articular pillar of C5 — pushes the top vertebra anteriorly through that joint, which helps open the right facet and frees the motion, allowing more left rotation. Placing the hand on the left facet or at the other level wouldn’t address the contralateral barrier as effectively, so they’re less likely to restore the desired rotation.