Thoracolumbar side bend ROM: which option correctly states the fulcrum location?

• A. Anterior aspect of the spinous process of S2
• B. Lateral aspect of the spinous process of S2
• C. Posterior aspect of the spinous process of S2
• D. Anterior aspect of the spinous process of S1

Answer: (C)

The main idea is to choose a stable, repeatable axis that represents the actual pivot point of the thoracolumbar region when you side-bend, while minimizing movement of the hips. Placing the fulcrum at the posterior aspect of the spinous process of S2 gives you that reliable axis right at the lumbosacral junction, close to the pelvis, so the measurement reflects thoracolumbar motion rather than pelvis rotation. The posterior surface is the easiest to palpate and aligns with the vertebral spinous structure, which helps keep the axis consistent across measurements. If you used an anterior or lateral location, or moved the axis to S1, the reading would drift because you’d be measuring motion around a different pivot or inviting unnecessary hip involvement. That’s why the posterior aspect of S2 is the standard fulcrum for thoracolumbar side bending ROM.