AK Biomechanics & Body Movement Analysis 3 — Questions and Answers
Question 1: In applied kinesiology, what does a 'bilateral weight shift test' primarily assess?
- Proprioceptive reflexes of the vestibular system
- The symmetry of weight-bearing through the lower extremities and pelvis (Correct answer)
- Muscle tone in the gluteal group bilaterally
- Cortical control of reciprocal inhibition
Correct answer: The symmetry of weight-bearing through the lower extremities and pelvis
The bilateral weight shift test reveals asymmetric loading patterns that may indicate pelvic imbalance, leg-length discrepancy, or compensatory postural adaptations.
Question 2: Which connective tissue structure provides the primary passive restraint against anterior tibial translation at the knee?
- Medial collateral ligament
- Anterior cruciate ligament (Correct answer)
- Posterior cruciate ligament
- Iliotibial band
Correct answer: Anterior cruciate ligament
The anterior cruciate ligament (ACL) is the main passive restraint preventing the tibia from sliding anteriorly relative to the femur.
Question 3: What is the primary determinant of whether a muscle acts as a prime mover or stabilizer in a given movement?
- Muscle fiber type composition
- The direction of the line of pull relative to the joint axis (Correct answer)
- Absolute cross-sectional area of the muscle
- The length of the muscle's tendon
Correct answer: The direction of the line of pull relative to the joint axis
The line of pull relative to the joint's axis of motion determines whether a muscle produces torque (prime mover) or compressive joint force (stabilizer).
Question 4: During normal walking, at which phase of the gait cycle does peak hip extension occur?
- Initial contact
- Loading response
- Terminal stance (Correct answer)
- Pre-swing
Correct answer: Terminal stance
Peak hip extension occurs during terminal stance as the body pivots over the stance foot and the trailing limb reaches maximum extension before toe-off.
Question 5: The screw-home mechanism of the knee involves which motion as the joint reaches full extension?
- Tibial internal rotation
- Tibial external rotation (Correct answer)
- Fibular inferior glide
- Posterior meniscal translation
Correct answer: Tibial external rotation
As the knee reaches full extension, the tibia externally rotates on the femur (or the femur internally rotates on a fixed tibia), locking the joint into the close-packed position.
Question 6: Which law states that bone tissue is deposited along lines of mechanical stress and resorbed where stress is absent?
- Hooke's Law
- Wolff's Law (Correct answer)
- Newton's Third Law
- Davis's Law
Correct answer: Wolff's Law
Wolff's Law describes the adaptive remodeling of bone in response to mechanical loading, with trabecular bone aligning along principal stress trajectories.
Question 7: A client presents with forward head posture. Which cervical movement is characteristically restricted as a compensatory adaptation?
- Cervical rotation
- Upper cervical flexion / chin tuck (Correct answer)
- Cervical lateral flexion
- Lower cervical extension
Correct answer: Upper cervical flexion / chin tuck
Forward head posture involves upper cervical extension and lower cervical flexion; upper cervical flexion (chin tuck) is typically restricted as the suboccipital muscles adaptively shorten.
AK Biomechanics & Body Movement Analysis 3
In applied kinesiology, what does a 'bilateral weight shift test' primarily assess?