CCSP Clinical Biomechanics in Sports 3 — Questions and Answers
Question 1: In overhead throwing, the late cocking phase places the greatest tensile stress on which structure?
- Supraspinatus tendon
- Anterior capsule and inferior glenohumeral ligament (Correct answer)
- Posterior capsule
- Acromioclavicular ligament
Correct answer: Anterior capsule and inferior glenohumeral ligament
Maximum shoulder external rotation during late cocking produces peak tension in the anterior capsule and IGHL, the primary static restraint to anterior translation.
Question 2: Which biomechanical variable best predicts ACL loading during a single-leg landing task?
- Hip abductor strength alone
- Peak knee valgus moment (Correct answer)
- Quadriceps-to-hamstring ratio at low velocity
- Ankle dorsiflexion range of motion
Correct answer: Peak knee valgus moment
Peak knee valgus moment during landing has the strongest association with ACL strain and is the primary target of injury-prevention programs.
Question 3: The concept of 'joint centration' refers to:
- Maximizing joint range of motion through stretching
- Positioning articular surfaces for optimal congruency and load distribution (Correct answer)
- Centering the body's COM over the base of support
- Aligning spinal vertebrae in neutral lordosis
Correct answer: Positioning articular surfaces for optimal congruency and load distribution
Joint centration (DNS concept) means placing articular surfaces in the position of maximal congruence to distribute load evenly and minimize focal stress.
Question 4: A cyclist presents with anterior knee pain. Raising the saddle height primarily reduces stress on the:
- Patellar tendon (Correct answer)
- Medial collateral ligament
- Iliotibial band
- Hamstring origin
Correct answer: Patellar tendon
Lowering the saddle increases knee flexion angle and patellar tendon load; raising the saddle reduces peak knee flexion and patellar tendon stress.
Question 5: Force closure of the sacroiliac joint is provided by:
- Sacral morphology alone
- Muscular and ligamentous compression across the joint (Correct answer)
- Hydraulic pressure from the nucleus pulposus
- Gravitational loading through the femoral head
Correct answer: Muscular and ligamentous compression across the joint
Force closure refers to active muscular contraction (e.g., biceps femoris, gluteus maximus) and ligament tension that compress the SI joint to enhance stability.
Question 6: During a deadlift, the moment arm of the load relative to the lumbar spine is LONGEST when:
- The barbell is directly under the shoulder joint
- The barbell is held close to the body throughout the lift
- The barbell drifts anteriorly away from the body (Correct answer)
- The athlete uses a sumo stance
Correct answer: The barbell drifts anteriorly away from the body
When the barbell drifts forward, the horizontal distance between the load and the lumbar fulcrum increases, dramatically raising the lumbar extensor moment.
Question 7: Kinetic chain dysfunction where proximal segment weakness leads to distal compensatory injury is best illustrated by:
- Rotator cuff impingement caused by weak hip abductors during throwing (Correct answer)
- Plantar fasciitis caused by Achilles tightness alone
- Lateral epicondylalgia caused by wrist extensor overuse only
- Patellar tendinopathy caused by quadriceps hypertrophy
Correct answer: Rotator cuff impingement caused by weak hip abductors during throwing
Weak hip stabilizers increase trunk tilt, alter scapular position, and raise shoulder impingement risk—a classic proximal-to-distal kinetic chain failure.
CCSP Clinical Biomechanics in Sports 3
In overhead throwing, the late cocking phase places the greatest tensile stress on which structure?