Biomechanics Final

Kinesiology

The study of movement.

Force

A push or pull acting on the body.

Class II lever efficiency

Class II levers have a longer internal moment arm than they do external moment arm.

Lever arm direction

Perpendicular to the fulcrum and force.

Compression

The type of stress a long bone is best suited to handle.

Class III lever

When the resistance moment arm is longer than the effort moment arm.

Translation

Movement observed when force is exerted and movement occurs but there is no torque.

Class I lever

When internal moment arm is 10 cm on one side and external moment arm is 1 cm on the opposite side of the fulcrum.

Greenstick fracture location

The anterior superior aspect of the collarbone (the tension side).

Anatomical structure

The thumb is the most lateral structure in anatomical position.

Sagittal plane

Divides the body into left and right.

Radial/ulnar deviation axis

Occurs on the sagittal axis.

Distal structure

The talocrural joint is the most distal structure.

Wolff's Law

Bones are remodeled according to the strain placed upon them.

Sesamoid bones

Found embedded in tendons.

Glenohumeral joint degrees of freedom

Has 3 degrees of freedom.

Goniometer measurement

The stationary arm remains fixed in line with an anatomical landmark and the movement arm tracks the motion.

Growth center of the bone

Known as the epiphyseal plate.

Yield point tissue response

The shape is permanently altered though not fully torn.

Axial skeleton

Includes the skull, vertebrae, and sternum.

Neuroplasticity

The ability of the brain to form or reorganize connections in response to learning, particularly after an injury.

Parietal lobe function

Sensory processing.

Frontal cortex function

Executive functioning.

Cerebellum function

Prediction center/movement control.

Thalamus function

Relay center.

Motor vs. sensory homonculus

Gums and teeth are only present on one homonculus.

Peripheral nervous system structure

The sciatic nerve.

Lower extremity nerves structure

The lumbosacral plexus.

Decussating signals implications

Can have function in one pathway but not the other at the same level or body region.

Upper motor lesion deficits

Hyperreflexia.

Lower motor neuron lesion implications

Requires a catheter/colostomy bag due to inability to hold contents.

Motor unit definition

A motor neuron and all the muscle fibers it innervates.

Closed learning environment characteristics

Practicing multiple tasks in sequence in the kinesiology lab with a tutor.

Variable learning example

A pitcher alternating pitches during practice.

Hick's Law

As the amount of response alternatives increases, reaction time gets slower.

Skilled 100m sprinter muscle fiber type

Type II B muscle fibers.

Passive insufficiency example

Decreased hip flexion when the knee is extended due to hamstring length.

Shoulder separation injury

Injures the AC joint.

Humeral head direction

Points backwards in relation to the bottom of the humerus.

Warm-up components

Dynamic warm-up and activity-specific warm-up.

Extensor tendons compartments

Run through bony compartments.

Reverse muscle action example

The gluteus medius during a side plank.

Intrinsic force counteracting head position

Cervical extensors.

Scapula attachment to axial skeleton

Through the SC joint via the AC joint.

Stages of healing with active swelling

The inflammatory phase.

Acetabulum bones

The pubic bone, ilium, and ischium comprise the acetabulum; sacrum is not part.

Talocrural joint composition

Does not include the calcaneus.

Primary ACL role

Resists anterior tibial translation and rotation.

Emergent condition from increased lower leg pressure

Compartment syndrome.

Flexor pronator muscle mass location

Located at the medial epicondyle.

Asymmetrical step length gait pattern

Antalgic gait.

Wide base of support gait pattern

Shuffling gait.

Functional unit of gait

A stride includes two steps.

Longer phase in gait

The stance phase is longer.

Phase with lowest ground reaction force

Loading response.

Muscle activation at phase change (ball release)

All of the above occurs at point of release.

EMG function

Shows electrical activity in a muscle.

Medial patella femoral ligament purpose

Provides patellar stability by resisting lateral slipping.

Knee valgus position description

Ankle is lateral to the midline relative to the knee.

Tibial osteotomy condition

Performed to improve patellar stability for tibial torsion.

Front squat teaching tool

Increases emphasis on upright positioning and trunk control crucial for squatting.

Primary mover for RDL

Gluteals.

Best stretch for pectoralis major

Shoulder abduction and external rotation.

Decreasing ground reaction forces during jogging

Land with increased knee and hip flexion and on the forefoot.

Resultant force magnitude finding method

Place vectors tip to tail and connect the open tail to the open tip.

Weight distribution for maximizing driving distance in golf (setup)

Evenly distributed between front and back legs.

Weight distribution during backswing (arm parallel position)

On the back foot.

What plane of motion do horizontal abduction and adduction occur on?

Transverse.

What axis of rotation do horizontal abduction and adduction occur on?

Longitudinal.

What plane of motion does scapular elevation and depression occur in?

Frontal (coronal).

Define circumduction.

The circular motion of a body part that combines flexion/extension/abduction and adduction.

How many degrees of freedom does the shoulder have?

Define a motor unit.

A single motor neuron and all the fibers it innervates.

How does a muscle undergo hypertrophy or get larger as a result of resistance training?

Muscle fiber diameter grows.

What type of skeletal muscle is primarily utilized by marathon runners?

Type I.

Which motor units turn on first according to Henneman’s Size Principle?

Slow twitch.

What type of muscle contraction is occurring when the muscle is lengthening during contraction?

Eccentric.

A muscle serving to slow the movement caused by the primary mover is known as the what?

Antagonist.

What do ligaments connect?

Bone to bone.

Define the role of a muscle stabilizer.

Acts to maintain the position of a joint or body segment against an outside force.

Where does the brachialis muscle insert?

Coronoid process of the ulna.

Which of the following muscles acts on both the ankle and the knee: Soleus, posterior tibialis, fibularis longus, or gastrocnemius?

Gastrocnemius.

If the flexor digitorum profundus was torn distally, which joint movement would be most adversely affected?

DIP flexion.

Which of the following muscles is an example of parallel muscle fiber arrangement: External oblique, rectus abdominis, deltoid, or rectus femoris?

Rectus abdominis.

Which of the following muscles is an example of multipennate muscle fiber arrangement: External oblique, rectus abdominis, deltoid, or rectus femoris?

Deltoid.

Which of the following is an example of a reverse muscle action: The hamstrings during a Nordic curl, the latissimus dorsii during a lat pull down, the gastrocnemius during a calf raise, or the gluteus medius during a standing hip abduction exercise?

The hamstrings during a Nordic hamstring curl.

When the hand intrinsics activate, what are the corresponding actions?

Flexion of the metacarpophalangeal joint, extension of the proximal phalangeal joint, and extension of the distal phalangeal joint.

How do muscle spindles help protect you from getting injured?

They activate the muscles when they sense a dangerous amount of passive stretch.

What type of joint is found between the tibia and the fibula?

Syndesmoses.

Where do you find the interneuron, where the muscle stretch reflex occurs?

The spinal cord.

Which of the following is a pivot point: the atlantoaxial joint, the atlantooccipital joint, C3-7 intervertebral joints, or the lumbar spine intervertebral joints?

The atlantoaxial joint.

Which of the following is a hinge joint: The radiocarpal joint, the lumbar spine, the metacarpophalangeal joints, or the tibiofemoral joint?

The tibiofemoral joint.

Why does the articular cartilage have little ability to heal?

It has minimal to no blood flow.

When measuring cervical flexion, where should you line the fulcrum and the moving arm up?

The external auditory meatus (ear hole) and the nose.

What is the role of fibrocartilage in the knee?

All of the above: the menisci helps distribute loads over the joint surfaces, improves the fit of the articulating joint surfaces, and absorbs shock at the joint.

Define closed-pack positioning.

The maximum contact between articulating bony surfaces and is more stable.

Which of the following is part of the appendicular skeleton: The humerus, the skull, the sternum, or the spinal column?

The humerus.

What is the primary role of the rotator cuff?

Neutralizing agonist muscle forces.

If you are doing yoga and are holding stretching poses for at least 30 seconds, what type of stretching are you performing?

Static stretching.

Wolff’s law of bone growth states that increased stress on a bone will result in what changes to that bone?

Increased bone formation.