Thoracolumbar side bend ROM requires which of the following as the correct fulcrum location?

• A. Anterior aspect of spinous process of S2
• B. Posterior aspect of spinous process of T1
• C. Posterior aspect of spinous process of S2
• D. Posterior aspect of spinous process of L2

Answer: (C)

For measuring thoracolumbar lateral flexion, the axis of rotation (fulcrum) is placed at the posterior aspect of the spinous process of S2. This provides a stable pivot at the base of the spine so the movement measured comes mainly from the thoracolumbar region, not the pelvis or upper segments. Using this landmark helps keep the motion isolated and the readings reproducible, since S2 stays relatively fixed during side bending. Placing the fulcrum at a higher level (like near T1 or L2) or at a different surface (anterior aspect) would involve more motion from other regions or be harder to palpate and align, leading to less accurate measurements.