COF Biomechanics & Gait Analysis 4

Question 1

The 'center of pressure' (COP) path during normal gait typically travels from:

Accepted Answer

Lateral heel progressing medially toward the first metatarsal head at toe-off

Answer

The COP normally travels from the lateral heel at initial contact, progresses anteriorly along the lateral foot, then shifts medially across the metatarsal heads toward the hallux at push-off.

Question 2

In the context of lower limb orthotic prescription, 'ground reaction AFO' (GRAFO) achieves knee extension control primarily by:

Accepted Answer

Positioning the ankle in plantarflexion to shift the GRF anterior to the knee

Answer

A GRAFO prevents ankle dorsiflexion, keeping the GRF anterior to the knee joint axis, which creates a passive knee extension moment and stabilizes a weak or hyperextending knee.

Question 3

A patient presents with excessive knee flexion (crouch gait) throughout stance phase. Which muscle group weakness is the PRIMARY contributor to this pattern?

Accepted Answer

Ankle plantarflexors

Answer

Crouch gait is primarily associated with weakness or insufficiency of the ankle plantarflexors, which normally provide a knee extension moment during mid-to-terminal stance.

Question 4

The 'windlass mechanism' of the foot refers to:

Accepted Answer

Tightening of the plantar fascia during toe dorsiflexion that raises the medial arch

Answer

The windlass mechanism describes how dorsiflexion of the toes (especially the hallux) tightens the plantar fascia around the metatarsal heads, elevating the medial longitudinal arch and supinating the foot.

Question 5

Which metric best quantifies the energetic cost of ambulation relative to body weight and walking speed?

Accepted Answer

Oxygen consumption per unit distance (O2 cost)

Answer

Oxygen consumption per unit distance (mL O2/kg/m) normalizes metabolic cost for body weight and walking speed, allowing comparison across patients and conditions.

(COF) Certified Orthotic Fitter Practice Test

(COF) Certified Orthotic Fitter Practice Test

COF Biomechanics & Gait Analysis 4