Kinesiology & Biomechanics Flashcards

In orthopedic massage, understanding the closed-packed position of a joint is important because in this position the joint is:

Answer: Most congruent with maximum ligamentous tension

In the closed-packed position, joint surfaces are maximally congruent, ligaments are taut, and the capsule is under greatest tension, making it the most stable but least accessible position.

Which kinematic concept describes the motion of one joint surface rolling and sliding on the opposing surface simultaneously?

Answer: Arthrokinematics

Arthrokinematics describes the small accessory motions (roll, slide, spin) that occur between joint surfaces during physiological movement.

According to the convex-concave rule in joint mobilization, when a convex surface moves on a fixed concave surface, the roll and slide occur in which directions?

Answer: Opposite directions

When a convex surface moves on a fixed concave surface, roll occurs in the direction of movement while the slide (glide) occurs in the opposite direction.

A therapist assesses 'length-tension relationship' when evaluating a muscle. What does this term describe?

Answer: The relationship between muscle resting length and its force-generating capacity

The length-tension relationship describes how a muscle's ability to generate force varies with its current length, with optimal force produced at resting length.

Which biomechanical principle explains why the lumbar spine is at greatest risk for injury during combined flexion, lateral flexion, and rotation?

Answer: Coupling motion and triaxial loading

Coupled motion combined with triaxial loading places simultaneous compressive, shear, and torsional stresses on lumbar discs and facet joints, dramatically increasing injury risk.

Which concept in kinesiology refers to the muscle's ability to maintain a contraction at a constant length without joint movement?

Answer: Isometric contraction

An isometric contraction produces muscle tension without a change in muscle length or joint angle, commonly used for stabilization.

During functional assessment of gait, excessive anterior pelvic tilt is most commonly associated with weakness or tightness in which muscle group combination?

Answer: Weak abdominals and hip extensors with tight hip flexors and lumbar extensors

Anterior pelvic tilt is classically caused by weak abdominals and hip extensors coupled with tight hip flexors (especially iliopsoas) and tight lumbar extensors, a pattern called 'lower crossed syndrome.'