Which parameter best describes the hip flexion angle for targeting L5-S1 during traction?

Which parameter best describes the hip flexion angle for targeting L5-S1 during traction?

• A. 0-15 degrees
• B. 60-75 degrees
• C. 75-90 degrees
• D. 45-60 degrees

Answer: (D)

The key idea is that the angle of hip flexion during lumbar traction changes the direction of the traction force along the spine, which levels of the lumbar region are most effectively loaded/unloaded. When the hips are flexed to a moderate amount—roughly in the mid-40s to around 60 degrees—the pelvis tilts just enough to align the traction line with the lower lumbar segments, including the L5-S1 junction. This mid-range angle helps achieve effective separation at L5-S1 while keeping the force comfortable and well tolerated. If hip flexion is kept very low, the pull tends to influence higher lumbar levels; if hip flexion is very deep (75-90 degrees), the line of pull shifts and may reduce the emphasis on L5-S1 or cause greater pelvic discomfort. Therefore, a mid-range hip flexion of about 45-60 degrees best targets L5-S1 during traction.

The key idea is that the angle of hip flexion during lumbar traction changes the direction of the traction force along the spine, which levels of the lumbar region are most effectively loaded/unloaded. When the hips are flexed to a moderate amount—roughly in the mid-40s to around 60 degrees—the pelvis tilts just enough to align the traction line with the lower lumbar segments, including the L5-S1 junction. This mid-range angle helps achieve effective separation at L5-S1 while keeping the force comfortable and well tolerated. If hip flexion is kept very low, the pull tends to influence higher lumbar levels; if hip flexion is very deep (75-90 degrees), the line of pull shifts and may reduce the emphasis on L5-S1 or cause greater pelvic discomfort. Therefore, a mid-range hip flexion of about 45-60 degrees best targets L5-S1 during traction.