Biomechanics test 1

what are the materials that form connective tissues within a joint?

fibrous proteins, ground substance, cells

what are the 3 forms of fibrous protein?

Type 1 collagen, type 2 collagen, elastin

describe type 1 collagen

thick rugged, found in ligaments, tendons, fibrous capsule

describe type 2 collagens

thinner/less stiff, articular cartilage

describe elastin

lower proportion, found in ligamentum flavor

what does ground substance contain?

gel like matrix where collagen and elastin meet. contains water, solute, proteins

what kind of tissues have ground substance ?

those with high compressive force

what are the 2 types of cells?

chondrocytes, fibroblasts

where are chrondocytes found?

articular cartilage, fibrocartilage

where are fibrocytes found?

ligaments, tendons supportive structures

where are osteocytes found?

in osteoblast

what are the types of periarticular connective tissues?

dense connective tissue, articular cartilage, fibrocartilage

dense connective tissue traits?

found in ligaments, tendons, articular spacehigh type in collagen and low elastin, nourishment from blood vessels

articular cartilage traits?

found in jointshigh in type 2 collagen, high in ground substance,nourishment from movement of synovial fluid

Fibrocartilage traits?

found in disc, labrum. meniscus,high in type 1 collagen, moderate in ground substance, nourishment from synovial fluid

all motion is either?

translation (rectilinear, curvilinear) or rotational angular

sagittal plane axis is?

transverse or ML

frontal plane axis is?

anterior, posterior

horizontal plane axis is?

vertical

how many degrees of freedom are there?

3

what is joint play?

term used to describe if joint is stiff or lax

What is osteokinematics?

movement of bones

What is arthokinematics?

movement of joints

what is roll?

multiple points along one rotating articular surface contact multiple points on another articular surface

what is slide?

A single point on one articular surface contacts multiple points on another articular surface

what is spin?

ex: elbow joint-a single point on one articular surface rotates about a single point on another articular surface

Convex-Concave Rule

roll and slide occur in opposite directions

concave-concave rule

roll and slide in same direction

Close-packed position?

joint orientation for which the contact between the articulating bone surfaces is maximum stability and max congruency

Loose-packed position?

all other joint positions, less contact area between surfaces

describe stress- strain curve

starts with elastic then plastic

What is viscoelasticity?

time dependent change in tissue- creep

what kind of force is muscle?

internal force

What kind of force is gravity?

external force

what are the3 types of contractions?

isometric, concentric, eccentric

sliding filament theory

myosin uses barbs to pull on actin

Agonist muscle

The muscle primarily responsible for movement of a bone.

antagonist muscle

The muscle opposite the agonist, which must relax and lengthen during contraction of the agonist.

synergist muscle

Muscle that assists a prime mover

force couple

Linear forces in opposite directions produce torque in one direction

1st class lever

axis of rotation between parallel forces, best advantage is IMA ratio is less than, greater than or = to 1

2nd class lever

resistance force is closer to axis than effort force calf muscle is example, advantage is IMA ratio is greater than 1

3rd class lever

effort force is closer to axis than resistance force, common and advantage is IMA ratio is less than 1 ex: bicep

what's the torque formula?

IFxD or EFxD