CPO Biomechanics & Gait Analysis Flashcards

During normal walking gait, which phase accounts for approximately 60% of the gait cycle?

Answer: Stance phase

Stance phase comprises roughly 60% of the gait cycle while swing phase accounts for the remaining 40%.

Which gait deviation is most commonly observed in a patient with a transtibial prosthesis that has excessive socket flexion?

Answer: Knee instability at midstance

Excessive socket flexion in a transtibial prosthesis shifts the ground reaction force posterior to the knee, causing instability at midstance.

What is the term for the forward progression of the body over a stationary foot during midstance?

Answer: Tibial advancement

Tibial advancement describes the forward progression of the tibia over the stationary foot during the stance phase of gait.

In amputee gait analysis, 'vaulting' on the sound limb is most often a compensatory mechanism for which prosthetic issue?

Answer: Prosthetic limb being too long

Vaulting (rising on the toe of the sound limb) is a compensatory strategy when the prosthetic limb is functionally too long, allowing foot clearance during swing.

The center of pressure (COP) path during stance phase normally progresses in which direction?

Answer: Posterior heel to metatarsal heads, medially to hallux

Normal COP progression moves from the posterior lateral heel forward along the lateral border to the metatarsal heads and then medially to the hallux.

Which biomechanical principle explains why a longer prosthetic keel results in a smoother rollover during late stance?

Answer: Extended lever arm smooths the transition through second and third rockers

A longer forefoot lever arm extends the effective rocker radius, smoothing the rollover transition from the second to third rocker during late stance.