Which combination of corrections would yield the greatest femur height increase in the provided dataset?

• A. 2 mm
• B. 4 mm
• C. 8 mm
• D. 6 mm

Answer: (D)

The effect of a correction on femur height is not simply proportional to how big the correction is—it's shaped by how the spine, pelvis, and hip joints interact. In this dataset, increasing the correction from small to mid-range improves the femur height, but pushing to the largest correction triggers extra compensatory changes elsewhere in the alignment that cancel part of that gain. The result is that the mid-range correction produces the greatest net increase in femur height, while too-small corrections underachieve and the largest correction overcorrects, reducing the overall height gain.