Which AFO limits dorsiflexion?

• A. AFO: Posterior leaf spring
• B. AFO: metal anterior stop
• C. AFO: valgus correction strap
• D. KAFO: Offset joint

Answer: (B)

This question hinges on how AFO designs control ankle motion. An anterior stop placed on the forward part of an AFO physically blocks the ankle from moving into dorsiflexion—when the shin moves toward the foot, the front of the orthosis contacts the leg and prevents further upward bending of the ankle. That’s why this design specifically limits dorsiflexion.

In contrast, a posterior leaf spring AFO sits at the back and is intended to allow or even assist dorsiflexion, not restrict it. A valgus correction strap is for coronal plane alignment and doesn’t directly limit ankle dorsiflexion. A KAFO with an offset joint primarily affects knee mechanics and isn’t a mechanism for restricting ankle dorsiflexion.