CPO CPO Biomechanics & Gait Analysis 2

Question 1

Which orthotic alignment principle ensures the knee joint center is positioned anterior to the ground reaction force vector during stance to promote stability?

Accepted Answer

Passive knee stability through GRF anterior to joint

Answer

Positioning the ground reaction force anterior to the knee joint center creates an extension moment, providing passive knee stability without active muscle effort.

Question 2

A transfemoral amputee demonstrates lateral trunk bending toward the prosthetic side during stance. Which prosthetic cause should be investigated first?

Accepted Answer

Prosthetic limb too short

Answer

A prosthetic limb that is functionally too short causes the patient to laterally bend toward that side to maintain balance and clear the floor.

Question 3

What does cadence refer to in clinical gait analysis?

Accepted Answer

Number of steps taken per unit time

Answer

Cadence is defined as the number of steps (or strides) taken per minute and is a fundamental temporal parameter of gait.

Question 4

During KAFO fitting, which biomechanical factor most influences the decision to set the knee joint in slight flexion rather than full extension?

Accepted Answer

Reducing energy expenditure during ambulation

Answer

A slight knee flexion angle (about 5°) in a KAFO reduces energy expenditure by allowing a more natural gait pattern with smoother weight transfer.

Question 5

Which parameter best describes the symmetry of a prosthetic user's gait and is frequently used to compare stance time between limbs?

Accepted Answer

Symmetry index (SI)

Answer

The symmetry index compares values (such as stance time) between limbs and quantifies the degree of asymmetry in prosthetic gait.

(CPO) Certified Prosthetist Orthotist Practice Test

(CPO) Certified Prosthetist Orthotist Practice Test

CPO CPO Biomechanics & Gait Analysis 2