PRE-TEST OP2

During sit-to-stand, which joint movement occurs first to shift the center of mass forward?

• Hip flexion

• Knee extension

• Ankle plantarflexion

• Trunk extension

• Ankle dorsiflexion

Which muscle group is primarily responsible for decelerating the leg during terminal swing in normal gait?

• Quadriceps

• Hamstrings

• Gastrocnemius

• Tibialis anterior

• Hip flexors

In carrying a heavy load in both hands, which biomechanical adaptation reduces lumbar stress?

• Excessive lumbar lordosis

• Keeping the load close to the body

• Bending from the waist

• Standing with feet close together

• Increasing thoracic kyphosis

Which gait deviation is most likely in a transfemoral amputee with weak hip abductors?

• Vaulting

• Circumduction

• Trendelenburg gait

• Hip hiking

• Excessive knee flexion in stance

While rising from a chair without arm support, the main biomechanical challenge is:

• Generating sufficient knee extensor torque

• Preventing hip hyperextension

• Maintaining plantarflexor endurance

• Avoiding lumbar kyphosis

• Controlling ankle inversion

Which muscle action is critical for controlled descent during stair negotiation?

• Concentric quadriceps contraction

• Eccentric quadriceps contraction

• Concentric hamstring contraction

• Eccentric hip flexor contraction

• Isometric gastrocnemius contraction

Which biomechanical factor most influences energy expenditure in prosthetic ambulation?

• Step width

• Stride length

• Cadence

• Symmetry of gait

• Arm swing

In lifting mechanics, the "squat lift" technique reduces:

• Hip extensor torque

• Knee flexor demand

• Lumbar shear forces

• Ankle dorsiflexion range

• Pelvic stability requirement

During crutch-assisted ambulation, which upper limb muscle group is most involved in weight-bearing?

• Deltoid

• Biceps brachii

• Triceps brachii

• Wrist extensors

• Latissimus dorsi

Which kinematic change is seen in elderly gait compared to young adults?

• Increased stride length

• Decreased double-support time

• Increased cadence

• Decreased push-off power

• Increased hip extension