During terminal stance and pre-swing, the external ankle moment is what?

During terminal stance and pre-swing, the external ankle moment is what?

• A. Plantarflexion
• B. High dorsiflexion
• C. Knee flexion
• D. Hip abduction

Answer: (B)

The key idea is how the ground reaction force creates a torque at the ankle. In terminal stance and pre-swing, the line of pull of the ground reaction force is in front of the ankle joint, which tends to rotate the ankle into dorsiflexion. At this stage of gait, the body’s muscles (notably the plantarflexors) are generating the push-off, but the external torque produced by the ground is in the dorsiflexion direction, often described as a high dorsiflexion moment. So, the external ankle moment during these phases is dorsiflexion. The other options don’t fit because they describe plantarflexion at the ankle or movements at other joints, which aren’t the direction of the external ankle moment in this part of the gait cycle.

The key idea is how the ground reaction force creates a torque at the ankle. In terminal stance and pre-swing, the line of pull of the ground reaction force is in front of the ankle joint, which tends to rotate the ankle into dorsiflexion. At this stage of gait, the body’s muscles (notably the plantarflexors) are generating the push-off, but the external torque produced by the ground is in the dorsiflexion direction, often described as a high dorsiflexion moment.

So, the external ankle moment during these phases is dorsiflexion. The other options don’t fit because they describe plantarflexion at the ankle or movements at other joints, which aren’t the direction of the external ankle moment in this part of the gait cycle.