During Sahrmann test stage 1, what describes the starting position and the leg movement while maintaining a constant lumbar pressure under the spine?

During Sahrmann test stage 1, what describes the starting position and the leg movement while maintaining a constant lumbar pressure under the spine?

• A. Crook lying with pressure biofeedback inflated to 40 mmHg under the lumbar spine; one leg lifted to tabletop while pressure and pelvic position are maintained.
• B. Supine with both legs lifted to tabletop with knees extended.
• C. Prone lying with the legs extended and hips lifted.
• D. Seated with legs extended and trunk upright.

Answer: (A)

The test is examining how well the deep abdominal muscles control and stabilize the lower spine as a leg moves, using a pressure biofeedback unit to keep the lumbar pressure constant. In stage 1 you start in crook lying—knees and hips flexed with feet on the table—and the pressure biofeedback cuff is inflated to 40 mmHg under the lumbar spine. From this position, you lift one leg to a tabletop position while maintaining the same pressure and keeping the pelvis from tilting. This setup creates a low-load, controlled challenge that emphasizes keeping the spine stable while the leg moves. Other positions would introduce different base-of-support or spinal movements and don’t isolate the same stabilization pattern used in stage 1.

The test is examining how well the deep abdominal muscles control and stabilize the lower spine as a leg moves, using a pressure biofeedback unit to keep the lumbar pressure constant. In stage 1 you start in crook lying—knees and hips flexed with feet on the table—and the pressure biofeedback cuff is inflated to 40 mmHg under the lumbar spine. From this position, you lift one leg to a tabletop position while maintaining the same pressure and keeping the pelvis from tilting. This setup creates a low-load, controlled challenge that emphasizes keeping the spine stable while the leg moves. Other positions would introduce different base-of-support or spinal movements and don’t isolate the same stabilization pattern used in stage 1.