Biomechanics & Body Movement Analysis Flashcards
7 cards from real AK practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Biomechanics & Body Movement Analysis flashcards as text
Which concept describes the sequential activation of proximal-to-distal body segments to maximize distal endpoint velocity?
Answer: Kinetic chain summation
Kinetic chain summation (or the kinetic link principle) describes how energy is transferred and amplified sequentially from larger proximal segments to smaller distal segments.
During shoulder abduction in the scapular plane, what is the normal glenohumeral-to-scapulothoracic rhythm ratio?
Answer: 2:1
The classic scapulohumeral rhythm is 2:1, meaning for every 3° of shoulder elevation, 2° occurs at the glenohumeral joint and 1° from scapular upward rotation.
Which foot structure acts as a rigid lever during the propulsion phase of gait?
Answer: The medial longitudinal arch wound up via the windlass mechanism
The windlass mechanism stiffens the plantar fascia when the toes are dorsiflexed, raising the medial arch and converting the foot to a rigid lever for push-off.
Applied kinesiology muscle testing involves evaluating a muscle in its 'challenged' position. What does a sudden give or muscle inhibition indicate?
Answer: Altered neural facilitation or an associated viscerosomatic reflex
In AK, a muscle that tests weak when challenged indicates neurological inhibition that may reflect viscerosomatic reflexes, meridian imbalances, or structural fixations.
Which of the following best defines 'open kinetic chain' exercise?
Answer: The distal segment moves freely while the proximal segment is stabilized
In an open kinetic chain, the distal segment (e.g., foot or hand) is free to move, such as a seated leg extension where the foot swings freely.
A force couple at the scapula involves which two muscles working together to produce upward rotation?
Answer: Serratus anterior and lower trapezius
Serratus anterior pulls the inferior angle of the scapula anterolaterally while the lower trapezius pulls the spine of the scapula inferiorly, creating a rotational couple for upward scapular rotation.
What is 'stress shielding' in the context of orthopedic biomechanics?
Answer: Reduced mechanical stress in bone adjacent to a rigid implant, leading to bone resorption
Stress shielding occurs when a rigid metal implant bears most of the load, reducing the mechanical stimulation to surrounding bone and causing adaptive resorption per Wolff's Law.