CO Anatomy, Biomechanics & Pathophysiology of the Musculoskeletal System 2

Question 1

Which ligament is the primary restraint to anterior translation of the tibia on the femur?

Accepted Answer

Anterior cruciate ligament

Answer

The anterior cruciate ligament (ACL) is the primary restraint preventing anterior tibial translation relative to the femur.

Question 2

The subtalar joint axis orientation primarily governs coupling between which two motions?

Accepted Answer

Inversion and eversion coupled with tibial rotation

Answer

The oblique subtalar joint axis couples subtalar inversion/eversion with internal/external tibial rotation during gait.

Question 3

In spastic cerebral palsy, the pathophysiologic basis for increased muscle tone is best described as:

Accepted Answer

Upper motor neuron lesion causing loss of inhibitory control over the stretch reflex

Answer

Spasticity results from an upper motor neuron lesion that releases the stretch reflex from descending inhibitory control, causing velocity-dependent tone increase.

Question 4

Which bone of the foot serves as the keystone of the medial longitudinal arch?

Accepted Answer

Navicular

Answer

The navicular bone acts as the keystone of the medial longitudinal arch and is the primary site of arch collapse in adult flatfoot.

Question 5

During normal gait, ground reaction force (GRF) passes anterior to the knee joint at approximately which phase?

Accepted Answer

Mid-stance

Answer

During mid-stance, the GRF vector typically passes anterior to the knee axis, creating an extension moment that reduces quadriceps demand.

(CO) Certified Orthotics Specialist Practice Test

(CO) Certified Orthotics Specialist Practice Test

CO Anatomy, Biomechanics & Pathophysiology of the Musculoskeletal System 2