MA I: torque, levers, kinetics, kinematics, classification of joints

Question 1

MA I

Torque formula

Answer 1

Force x Moment arm

Question 2

MA I

this class of lever has its axis of rotation (the fulcrum) positioned between the resistance (load) and the effort (muscle pull)

Answer 2

First-class lever

ex. triceps, head-and-neck

Question 3

MA I

In this type of lever, the resistance (load) is between the axis of rotation (fulcrum) and the effort (force)

Answer 3

Second-class lever

ex. calf muscles on the ankle

Question 4

MA I

In this type of lever, the effort (force) is located between the fulcrum and the resistance (load)

Answer 4

Third-class levers

ex. shoulder abduction, elbow flexor muscles

Question 5

MA I

The body’s ability to convert passive tension into useful work

Answer 5

Productive Antagonism

Question 6

MA I

What is the difference between kinetics and kinematics?

Answer 6

• Kinetics describes the effect of forces on the body. Ex. the stress-strain relationship, productive antagonism, internal/external forces, types of muscle contractions, classes of levers.
• Kinematics describes the motion of a body, without regard to the forces or torques that may produce the motion. Ex. arthrokinematics (roll, slide, spin), osteokinematics (planes of motion)

Question 7

MA I

two major classifications of joints based on movement potential

Answer 7

Synarthroses (fibrous/cartilaginous joints) and Diarthrosis (synovial joints)

Question 8

MA I

Symphysis pubis, epiphysial plates and the intervertebral discs of the spine are an example of what class of joints?

Answer 8

Cartilaginous Joints

Question 9

MA I

Sutures of the skull, distal tibiofibular joint, radioulnar joints are examples of what class of joints?

Answer 9

Fibrous Joints

Question 10

MA I

three major classifications of joints based on the types of tissue

Answer 10

Synovial, Cartilaginous (1st sternocostal joint), and Fibrous (sutures of the skull)

Question 11

MA I

The radiocarpal joint is an example of what type of synovial joint?

Answer 11

ellipsoid joint

Question 12

MA I

carpometacarpal joints (digits II to V) are an example of what type of synovial joints?

Answer 12

Plane Joint

Question 13

MA I

The metacarpophalangeal joint, tibiofemoral joint are examples of what type of synovial joints?

Answer 13

Condyloid Joint

Question 14

MA I

The carpometacarpal joint of the thumb is an example of what type of synovial joint?

Answer 14

Saddle Joint

Question 15

MA I

True or false: fat pads, bursae, and synovial plica are elements ALWAYS associated with diarthrodial (synovial joints) joints

Answer 15

False, these are elements that are sometimes associated with diarthrodial (synovial) joints.

Elements ALWAYS associated with synovial joints include synovial fluid, articular cartilage, joint capsule, synovial membrane, ligaments, blood vessels and sensory nerves.