OCS OCS Biomechanics & Kinesiology

Question 1

Which type of joint motion describes the rolling and gliding of one joint surface on another, as occurs at the knee during flexion?

Accepted Answer

Arthrokinematics

Answer

Arthrokinematics refers to the motion of joint surfaces relative to each other, including rolling, gliding, and spinning.

Question 2

The Q-angle is measured between the line of pull of the quadriceps and the patellar tendon; an abnormally increased Q-angle is most associated with which condition?

Accepted Answer

Patellofemoral pain syndrome

Answer

An increased Q-angle increases lateral patellar tracking forces, predisposing individuals to patellofemoral pain syndrome.

Question 3

During normal gait, which phase is characterized by maximal single-limb support and the greatest demand on the hip abductors?

Accepted Answer

Mid-stance

Answer

During mid-stance, the hip abductors (primarily gluteus medius) must generate sufficient force to prevent contralateral pelvic drop (Trendelenburg sign).

Question 4

The close-packed position of the glenohumeral joint, where the joint is most congruent and the capsule is most taut, is:

Accepted Answer

Full abduction and external rotation

Answer

Full abduction combined with external rotation places the glenohumeral joint in its close-packed position with maximum capsular tension and bony congruence.

Question 5

The scapulohumeral rhythm describes coordinated movement between the glenohumeral and scapulothoracic joints; what is the typical ratio of glenohumeral to scapulothoracic motion during shoulder abduction?

Accepted Answer

2:1

Answer

The classic scapulohumeral rhythm is approximately 2:1, meaning for every 3° of shoulder abduction, 2° occur at the glenohumeral joint and 1° at the scapulothoracic joint.

(OCS) Orthopedic Certified Specialist Practice Test

(OCS) Orthopedic Certified Specialist Practice Test

OCS OCS Biomechanics & Kinesiology