Thoracolumbar rotation ROM is measured with the patient in which position and stabilization?

• A. Position: Standing; Stabilize: Pelvis to prevent rotation; Fulcrum: over center of cranial aspect of head; Stationary Arm: Perpendicular to floor; Moving Arm: Parallel alignment of acromion processes
• B. Position: Supine; Stabilize: Pelvis to prevent rotation; Fulcrum: over center of cranial aspect of head; Stationary Arm: Parallel in line w/ both iliac crests; Moving Arm: Parallel alignment of acromion processes
• C. Position: Seated; Stabilize: Pelvis to prevent rotation; Fulcrum: over center of cranial aspect of head; Stationary Arm: Parallel in line w/ both iliac crests; Moving Arm: Parallel alignment of acromion processes
• D. Position: Seated; Stabilize: Pelvis to prevent rotation; Fulcrum: over center of cranial aspect of head; Stationary Arm: Perpendicular to floor; Moving Arm: Parallel alignment of acromion processes

Answer: (C)

The main idea is to isolate rotation of the thoracolumbar spine by preventing movement of the pelvis and using a consistent axis and landmarks. Seated with the pelvis stabilized, the hips can’t rotate, so any twist comes from the upper trunk. Placing the fulcrum over the center of the cranial aspect of the head sets the rotation axis where trunk rotation occurs, rather than involving neck or pelvic motion. The stationary arm aligned with the iliac crests provides a stable pelvic reference, while the moving arm aligned with the acromion processes follows how much the upper trunk rotates relative to that pelvis. This combination gives a reproducible measure of thoracolumbar rotation ROM. Other positions or different landmark alignments can allow pelvic or hip movement or misplace the axis, leading to less accurate isolation of the thoracolumbar rotation.