PAS Biomechanical Analysis & Movement 3

Question 1

In biomechanical analysis, what does the term 'moment arm' refer to?

Accepted Answer

The perpendicular distance from the joint axis to the line of force

Answer

The moment arm is the perpendicular distance from the joint's axis of rotation to the line of action of a force, determining torque magnitude.

Question 2

Which postural deviation is characterized by an exaggerated thoracic kyphosis combined with a flattened lumbar curve?

Accepted Answer

Sway-back posture

Answer

Sway-back posture features increased thoracic kyphosis, a posteriorly shifted pelvis, and a flattened lumbar spine.

Question 3

The 'Q-angle' is a measurement used to assess alignment of which joint?

Accepted Answer

Knee

Answer

The Q-angle measures the quadriceps angle at the knee, formed between the line from the ASIS to the patella and the patellar tendon to the tibial tubercle.

Question 4

What is the primary role of the deep longitudinal subsystem (DLS) during gait?

Accepted Answer

Force transmission from the foot through the ipsilateral posterior chain

Answer

The DLS (biceps femoris, sacrotuberous ligament, erector spinae) transmits ground reaction forces from the foot up through the posterior kinetic chain.

Question 5

During a squat, excessive forward lean of the torso is most likely caused by which limitation?

Accepted Answer

Limited ankle dorsiflexion

Answer

Limited ankle dorsiflexion forces the trunk to lean forward excessively to keep the center of mass over the base of support during a squat.

(PAS) Postural Alignment Specialist Practice Test

(PAS) Postural Alignment Specialist Practice Test

PAS Biomechanical Analysis & Movement 3