Exam 1 lecture: synovial jts and arthrokinematics

Question 1

biomechanical triad

Answer 1

skeleton, muscles, joints

Question 2

parts of long bone

Answer 2

diaphysis metaphysis (x2) epiphysis (x2) physis (x2)

Question 3

what is an apophysis?

Answer 3

accessory physis for tubercle, tuberosity, or epicondyle

Question 4

what is the most common joint type in the extremities?

Answer 4

synovial jt

Question 5

what is subchondral bone? what are its properties?

Answer 5

tip of epiphysis, deep to articular cartilage dense/cancellous/spongy bone; shock absorber

Question 6

what is synovial fluid made of?

Answer 6

GAGs - glycosaminoglycans *hyaluronic acid is most important GAG*

Question 7

functions of synovial fluid

Answer 7

shock absorption lubrication nutrient supply to cartilage waste removal from cartilage

Question 8

what happens if you don’t move your joints in regards to synovial fluid/cartilage?

Answer 8

decreased function due to no movement of nutrients in and out of cartilage; aging process speeds up

Question 9

2 layers of synovial membrane

Answer 9

intima: epithelioid layer subintima: CT layer

Question 10

which layer of the synovial membrane is vascularized?

Answer 10

subintima

Question 11

which layer of the synovial membrane is innervated?

Answer 11

subintima

Question 12

what are the functions of the synovial membrane?

Answer 12

produce and resorb synovial fluid immunity for joint cavity

Question 13

what are found in the transition zones of synovial membrane?

Answer 13

villi and fibrocartilage

Question 14

what types of cell would you find in the synovial membrane?

Answer 14

macrophages secretory fibroblast lipocyte

Question 15

what type of capillaries are in the synovial membrane? for what purpose?

Answer 15

fenestrated capillaries; increased fluid exchange

Question 16

t or f: the synovial membrane does not contain lymphatic vessels.

Answer 16

false.

Question 17

what type of CT is the fibrous joint capsule made up of?

Answer 17

dense irregular CT

Question 18

what are the functions of the fibrous joint capsule?

Answer 18

support/stabilize: static support guide and limit movements absorb shock

Question 19

t or f: the synovial joint capsule is inelastic and non-contractile.

Answer 19

true.

Question 20

static vs. dynamic support

Answer 20

dynamic support: comes from muscles static support: anything that is not muscle support; sometimes also referred to as primary support even though it is the last form of support before injury.

Question 21

Sharpey’s fibers

Answer 21

attachment sites of ligament to bone; blends together continuously (as opposed to a rigid line of transition)

Question 22

Wolff’s law

Answer 22

tissues react to external forces; tissues will adapt to forces placed on them

Question 23

t or f: the fibrous joint capsule is vascularized but not innervated.

Answer 23

false. the fibrous joint capsule is both vascularized and innervated.

Question 24

bursa: definition and function

Answer 24

a “sac” of fluid meant to help lubricate and cushion areas where two bones rub together - really a potential space

Question 25

t or f: some bursa communicate with joint capsules regularly, while others may communicate through defects in the capsule or not at all.

Answer 25

true.

Question 26

what is the most common type or articular cartilage?

Answer 26

hyaline cartilage

Question 27

what are the main components of articular cartilage?

Answer 27

low cell population density H2O (80% of total wt) collagen (60-70% of dry weight) GAGs (proteoglycans, 30-40% of dry weight)

Question 28

what is the function of collagen?

Answer 28

hold cartilage together resist shear & expansive forces

Question 29

what joints are lined by fibrocartilage?

Answer 29

AC jt SC jt TMJ 1/2 of SI jt

Question 30

t or f: collagen fibers are more parallel on bony side of cartilage cap and more perpendicular near articular surface.

Answer 30

false. fibers are more parallel near articular surface due to shear forces at the surface.

Question 31

what is important for GAGs to function?

Answer 31

GAGs must be sulfated for function

Question 32

give 4 examples of GAGs

Answer 32

chondroitin sulfate\* glucosamine sulfate\* keratin sulfate hyaluronic acid \*most important in cartilage matrix

Question 33

cartilage matrix is hydrophobic or hydrophilic?

Answer 33

hydrophilic

Question 34

why are small compressive loads better than large compressive loads on cartilage?

Answer 34

large compressive loads squeeze fluid film out of the cartilage.

Question 35

why are rapid oscillations/no oscillations bad?

Answer 35

decreased fluid exchange starves cartilage (e.g. immobilization, sustained load, vibratory tools)

Question 36

what changes occur in hydrostatic lubrication in DJD?

Answer 36

cell numbers decrease GAGs decrease decreased lubrication --\> serous fluid increases increased calcification

Question 37

what happens to the subchondral bone in DJD?

Answer 37

calcification --\> increased rigidity increased thickness --\> increased rigidity and impedes nutrient delivery/waste removal sclerosis on x-rays decreased shock absorption - more dense like cortical bone

Question 38

what causes DJD?

Answer 38

injury, wear and tear, increased mechanical stress, muscle weakness, abnormal support, decreased cartilage, decreased synovial fluid, aging, etc.

Question 39

4 joints that include a disc

Answer 39

AC (child --\> early 20's) SC TMJ ulnocarpal (TFC = triangular fibrocartilage)

Question 40

2 joints that include a meniscus

Answer 40

knee AC (late 20's --\> early 30's)

Question 41

2 types of intra-articular cartilage

Answer 41

disc, meniscus

Question 42

what type of cartilage is intra-articular cartilage?

Answer 42

fibrocartilage

Question 43

what are the functions of intra-articular cartilage?

Answer 43

shock absorption congruency stability decreased friction increased motion

Question 44

is intra-articular cartilage innervated/vascularized?

Answer 44

yes, but only the outer 1/3

Question 45

what are some effects of aging on intra-articular cartilage?

Answer 45

decreased vascularization decreased chondrocyte population decreased GAGs and collagen decreased shock absorption and flexibility increased collagen fiber size

Question 46

most extremity synovial joints are _______ and \_\_\_\_\_\_\_\_

Answer 46

diarthrodial, highly mobile

Question 47

3 joint classifications

Answer 47

simple compound complex

Question 48

simple joint

Answer 48

2 articular surfaces (1 articulation) simple joints usually have simple movements

Question 49

compound joint

Answer 49

2 or more articulations

Question 50

complex joint

Answer 50

1 or more articulations + intra-articular disc/meniscus

Question 51

joint complex

Answer 51

several joints acting together as a functional group

Question 52

what type of joint is the subtalar joint?

Answer 52

compound

Question 53

what type of joint is the tibiofemoral joint?

Answer 53

compound

Question 54

what type of joint is the patellofemoral joint?

Answer 54

compound

Question 55

what are some examples of joint complexes?

Answer 55

knee, shoulder, elbow, wrist, etc.

Question 56

what type of joints are the MP joints?

Answer 56

simple

Question 57

what type of joint is the AC joint?

Answer 57

complex

Question 58

name a joint that is both a complex joint and a joint complex

Answer 58

elbow, wrist, knee

Question 59

name a joint that is a joint complex but not a complex joint.

Answer 59

ankle

Question 60

what type of joint is the SC joint?

Answer 60

complex

Question 61

what type of joint is the TMJ?

Answer 61

complex

Question 62

what are the 6 anatomical/morphological joint classifications?

Answer 62

spheroid = enarthrosis = ball & socket ellipsoid = condyloid arthroid = planar = gliding sellar = saddle ginglymus = hinge trochoid = pivot

Question 63

what are examples of a spheroid joint?

Answer 63

hip, shoulder

Question 64

what is an example of an ellipsoid joint?

Answer 64

tibiofemoral jt

Question 65

what is an example of an arthroid joint?

Answer 65

carpal jts

Question 66

what is an example of a sellar joint?

Answer 66

thumb

Question 67

what is an example of a ginglymus joint?

Answer 67

MP joints

Question 68

what is an example of a trochoid joint?

Answer 68

head of radius to capitulum

Question 69

what are the 4 joint motion classifications?

Answer 69

angular (flexion, extention, abduction, adduction) translational (primarily gliding) rotational circumduction (combination of all of the above)

Question 70

what are the 4 joint classifications based on axes of motion?

Answer 70

uniaxial biaxial polyaxial nonaxial

Question 71

what is an example of a uniaxial joint?

Answer 71

IP joints

Question 72

what is an example of a biaxial joint?

Answer 72

MP joints

Question 73

what is an example of a polyaxial joint?

Answer 73

shoulder, hip

Question 74

what is an example of a nonaxial joint?

Answer 74

carpal joints

Question 75

what is the shape of most joints? why?

Answer 75

irregular ovoid; non-linear/accessory motions b/t joint surfaces

Question 76

what is the significance of crooked or crank shaped bones?

Answer 76

actions differ from joint motion

Question 77

t or f: osteokinematics is based on mechanical axis, not axis of rotation

Answer 77

true

Question 78

what are the two types of motion according to osteokinematics?

Answer 78

spin, swing

Question 79

what movement would be assoc. w/rotation causing an angular type of movement?

Answer 79

rotation of the head of the femur (spin) --\> flexion/extension of the femur

Question 80

when would spin cause rotation?

Answer 80

when mechanical axis is parallel to long axis

Question 81

t or f: in spin, the mechanical axis is stationary

Answer 81

true

Question 82

t or f: spin usually --\> rotation

Answer 82

false b/c bones are crooked/crank shaped

Question 83

t or f: pure spin does not occur

Answer 83

true

Question 84

what movement does spin usually accompany?

Answer 84

swing

Question 85

why do we not use spin synonymously w/rotation?

Answer 85

spin can produce angular or rotational movement

Question 86

what is impure swing?

Answer 86

spin + swing

Question 87

what is the screw home mechanism?

Answer 87

knee must externally rotate during last 15˚ of extension

Question 88

what is the screw home mechanism a good example of?

Answer 88

conjoint rotation

Question 89

what is arthrokinematics?

Answer 89

joint classification based on movement at articular surfaces

Question 90

what are the 3 types of movement assoc. w/arthrokinematics?

Answer 90

rolle slide/glide spin

Question 91

what is conjoint rotation?

Answer 91

roll + slide + spin

Question 92

what are the problems with pure roll?

Answer 92

progression distraction impingement

Question 93

what are the problems with pure slide?

Answer 93

progression distraction impingement

Question 94

what is the most common movement happening in an adjustment?

Answer 94

slide

Question 95

which always moves in the direction of angular movement: roll or slide?

Answer 95

roll

Question 96

what is the rule for a convex on a concave surface?

Answer 96

slide is opposite roll

Question 97

what is the rule for a concave on a convex surface?

Answer 97

slide is in the same direction as roll

Question 98

conjunct/conjoint rotation

Answer 98

accessory rotation due to spin and swing occuring together

Question 99

closed/tight packed position

Answer 99

joint, muscles, etc. are tight - joint surfaces are drawn closer together (e.g. end range of motion)

Question 100

open/loose packed position

Answer 100

little tension in capsule, room for movement

Question 101

resting position

Answer 101

most loose packed position

Question 102

neutral position

Answer 102

standard 0˚ when measuring ROM

Question 103

end play

Answer 103

joint is most prone to injury at end of ROM

Question 104

what are the 7 functions of muscle?

Answer 104

shock absorption dynamic joint stabilization dynamic joint alignment acceleration deceleration heat production venous circulation

Question 105

name the 3 types of muscle contraction

Answer 105

isometric isotonic isokinetic

Question 106

isometric contraction

Answer 106

no change in length of muscle, no movement

Question 107

isotonic contraction

Answer 107

produces joint motion w/variable velocity concentric: muscle shortening eccentric: muscle lengthening, often more stress on muscle/tendon than concentric

Question 108

isokinetic contraction

Answer 108

produces joint motion w/no constant velocity

Question 110

what are extracapsular ligs?

Answer 110

ligaments that are not a part of the capsule, but support the capsule

Question 111

what are the thickenings of the capsule?

Answer 111

capsular ligaments