If the dorsiflexion stop is set to allow only slight DF (~5°), knee motion results?

If the dorsiflexion stop is set to allow only slight DF (~5°), knee motion results?

• A. Knee extension
• B. Knee varus
• C. Knee flexion
• D. Knee valgus

Answer: (C)

Limiting ankle dorsiflexion to only a small amount changes how the leg moves during stance. When the ankle can’t dorsiflex much, the tibia can’t advance forward over the foot as readily. To keep the body progressing over the foot despite that stiff ankle, the knee compensates by flexing more. This knee flexion helps absorb load and maintain forward progression when the ankle’s dorsiflexion is restricted. Knee extension would stall progression, and knee valgus/varus are side-to-side alignment changes not driven by this ankle limitation.

Limiting ankle dorsiflexion to only a small amount changes how the leg moves during stance. When the ankle can’t dorsiflex much, the tibia can’t advance forward over the foot as readily. To keep the body progressing over the foot despite that stiff ankle, the knee compensates by flexing more. This knee flexion helps absorb load and maintain forward progression when the ankle’s dorsiflexion is restricted. Knee extension would stall progression, and knee valgus/varus are side-to-side alignment changes not driven by this ankle limitation.