MSK 2 - Joints & Skeletal Muscle Flashcards
1
Q
What is a joint
A
Articulation of two bones
2
Q
What is the purpose of a joint
A
Allow or limit movement, facilitate growth
3
Q
What is articular cartilage
A
hyaline cartilage, covers the smooth articular surface of bones
4
Q
What is an articular surface of bone
A
Smooth end
5
Q
What is supportive cartilage
A
Fibrocartilage, creates a better fit between bones
6
Q
What are ligaments
A
dense regular connective tissue, connect bone to bone, keeps joints together
7
Q
What are the two general joint classifications
A
Structural, functional
8
Q
What is structural joint classification
A
By the tissue that connect the bones
9
Q
What is functional classification of joints
A
ROM of joint
10
Q
What is the relationship between joint mobility and stability
A
More mobile, less stable
11
Q
What is hyaline cartilage reminent of
A
Endochondral ossification of bone
12
Q
What are fibrous joints
A
joined by fibrous connective tissue (dense irregular)
13
Q
What are three types of structural joint classifications
A
Fibrous, cartilaginous, synovial
14
Q
What are three types of fibrous joints
A
Suture, gomphosis, syndesmosis
15
Q
What are suture joints
A
Joint specific to the skull where bone are close together and joined by sutural ligaments
16
Q
Describe the mobility of suture joints
A
Infants: slightly movable, joined by sutural ligaments, for growth and birth
Adults: immovable
17
Q
What are gomphosis joints
A
Specific to teeth, peg and socket joint connecting tooth to bone
18
Q
What type of ligament joins a suture joint
A
Suture ligaments
19
Q
What type of ligament joins a gomphosis joint
A
periodontal ligaments
19
Q
What are syndesmosis joints
A
Joints joined by longer sheets of connective tissue such as interosseous membranes
20
Q
Describe the mobility of gomphosis joints
A
Some movement
20
Q
Where are suture joints found
A
Skull
21
Q
Where are gomphosis joints found
A
Upper and lower jaw
22
Q
Where are syndesmosis joints found
A
Between radius / ulna, tibia / fibula, etc
23
What is a cartilaginous joint
Joint joined by cartilage
23
What are the two types of cartilaginous joints
Synchondrosis and symphysis
24
What is a synchondrosis
Cartilaginous joint joined by hyaline cartilage; temporary; epiphyseal plates
25
What do synchondrosis joints allow for
Growth (not movement)
25
What is an important example of a synchondrosis
epiphyseal plates
26
What is a symphysis
cartilaginous joint joined by fibrocartilage; midline
27
Where can you find symphysis
midline joints such as pubic symphysis, intervertebral discs
28
What is a synostosis
An ossified joint that is immobile, bone holding together bone
29
Via which type of ossification does an epiphyseal plate ossify
endochondral
30
What are two examples of synostosis
ossified suture, epiphyseal lines
31
What is a synovial joint
Bones joined by a fibrous capsule (dense irregular tissue) enclosing a cavity around a joint
32
What is the most mobile joint
synovial
33
What is the most numerous joint
synovial
34
What is the most injury prone joint
synovial
35
What is an articular (synovial) capsule
Binds two bones together and surrounds the articular (synovial) cavity
36
37
What is the articular (synovial) cavity
Narrow space containing a thin layer of synovial fluid
38
What is the consistency and function of synovial fluid
Consistency: egg whites, changes with age
Function:
- reduces friction
- absorbs shock
- provides nutrients and removes waste for the articular cartilage
39
What is articular (synovial) cartilage
avascular hyaline cartilage that covers the articular surfaces of bones
40
What is the function of articular (synovial) cartilage
support and protect bone, reduces friction between bone, absorbs shock
40
How does articular (synovial) cartilage receive nutrients
avascular, but through synovial fluid
41
What are three supportive structures common to synovial joints (most, not all)
ligaments, supportive cartilage, bursa
42
What are the three types of ligaments
extracapsular (outside articular capsule), intracapsular (inside articular capsule), capsular (thickening of the articular capsule)
43
What are extrinsic ligaments
support joint, affect ROM
44
what are intrinsic ligaments
bind joint together
45
what are the three categories of supportive cartilage
articular disc, meniscus, labrum
46
What are articular discs
complete discs that divide the synovial cavity, affect joint movement
47
what are meniscus
incomplete discs found in places of poor fit between two bones to improve fit, redistribute weight, and absorb shock
48
What are labrum
lips of fibrocartilage that deepen shallow sockets with support large attachments, common to ball and socket joints
49
What is a bursa
sac like structures similar to synovial capsules found part of joint cavity or areas of friction between bone and skin
50
what is the function of a bursa
reduce friction, inside layer has a synovial membrane which secretes synovial fluid
51
What is a tendon (synovial) sheath
tube-like bursa that wrap around long tendons
52
What are the three main types of arthritis
rheumatoid, osteoarthritis, crystal arthritis (gout)
53
What is rheumatoid arthritis
autoimmune, body attacks synovial membranes
54
what is osteoarthritis
occurs due to wear and tear of joints due to age, decrease in synovial fluid production with age, cusion of joints lost, results in bone on bone contact
55
what is crystal arthritis (gout)
accumulation of uric acid crystalizes in joint structures and erodes joint structure
56
what is bursitis
inflammation of bursa
57
what is the cause and effect of bursitis
caused by irritation from repetitive use, results in pain and reduced range of motion
58
what types of structure may be compressed or damages from bursitis
joint space, cartilage, tendons, nerves
59
what are the three types of movements
angulation, rotation, gliding
60
what is angulation
change of angle in between axes of articulating bones (flexion, extension, adduction, abduction)
61
62
what is gliding
articulating surfaces slide on each other
63
what is a place joint
articulating surfaces flat or slightly curved
64
what type of motion occurs at a plane joint
gliding
65
where are plane joints found
clavicle and sternum, clavicle and scapula, carpals, tarsals
66
what is a pivot joint
rounded surface of one bone articulates with a ring formed by another bone and ligament (skip it)
67
what type of motion does a pivot joint perform
rotation
68
where are pivot joints found
cervical vertebrae 1 and 2, radius and ulna
69
what is a hinge joint
convex surface of one fits into concave of another bone
70
what type of motion is performed at a hinge joint
angulation; flex and extend (one direction only)
71
what is flexion
decrease the angle between the articulating bones, moving away from anatomical position
72
what is extension
increase the angle between the articulating bones, moving back to from anatomical position
73
what plane does flexion and extension occur on
sagittal place
74
what is dorsiflexion
flexing the foot
75
what is plantarflexion
pointing the foot
76
what is hyperextension
continuation of extension beyond anatomical position
77
what is a condylar joint
oval shaped condyle rests on elliptical cavity of another, rounded portion on rounded depression
78
what type of motion does a condylar joint perform
angulation; flex, extend, abduct, adduct
79
what is adduction
towards the midline of body
80
what is abduction
away from midline of body
81
what plane does adduction and abduction occur in
coronal / frontal
82
what is a saddle joint
articulating bones are convex-concave and fit into one another
83
what type of motion does a saddle joint perform
angulation; flex, extend, adduct, abduct
84
what is an example of a saddle joint
thumb
85
what is circumduction
if you can flex, extend, adduct, and abduct, you can circumduct
combines all four where distal end of joint can move in circle
86
what is a ball and socket joint
ball like surface of one rests against cuplike depression of another
87
what type of motion can a ball and socket joint perform
angulation (circumduction) and rotation
88
example of a condylar joint
wrist
88
examples of a call and socket joint
shoulder and hip
89
example of a hinge joint
knee and elbow
90
what is lateral (external) rotation
rotation of the anterior surface away from the midline
91
what is medial (internal) rotation
rotation of the anterior surface toward the midline
92
what is lateral flexion
side to side bending specific to the vertebral column
93
what plane does lateral flexion occur in
coronal plane
94
name two pairs of movements specific to the scapula and mandible
elevation / depression, protraction / retraction
95
what is elevation of a joint
movement upward away from anatomical position
96
what is depression of a joint
movement downward back to anatomical position
97
what is protraction of a joint
forwards movement away from anatomical position
98
what is retraction of a joint
backward movement returning to anatomical position
99
what plane does protraction / retraction occur in
transverse
100
name factors that can increase and decrease range of motion
increase: structure of joint, hormones
decrease: structure of joint, soft tissue, disuse
101
what are the three types of muscular tissue
skeletal, cardiac, smooth
102
is skeletal muscle striated / non striated and voluntary / involuntary
striated, voluntary
103
What are the main functions of muscle and muscular system
produce movement, stabilize body positions, store and move substances, produce heat (involuntary contractions, shivering)
104
What are 4 key muscle properties
electrical excitability, contractility, extensibility, flexibility (return to original length and shape)
105
What is muscle tissue derived from
mesoderm
106
What are myoblasts
differentiated form of mesoderm, fuse to form muscle fibers
107
what are satellite cells in muscle
myoblasts that remain around muscle fibers with limited ability to regenerate
108
What are muscle fibers made of
myofibrils
109
What are muscle fascicles made of
muscle fibers
110
What are muscle bellys made of
muscle fascicles
111
What is hypertrophy
Muscle growth
112
How does hypertrophy occur
- forceful, repetitive muscle activity
- skeletal muscle fiber number determined at birth
- muscle fibers grow
- number of myofibrils and mitochondria increase
113
What is a muscle cell
a muscle fiber
114
What is a sarcolemma
plasma membrane of a muscle fiber (surrounds muscle fiber)
115
What is sarcoplasm
cytoplasm within sarcolemma
116
what does sarcoplasm contain
myofibrils, mitochondria, myoglobin, glycogen, sarcoplasmic reticulum
117
What is myoglobin
O2 binding protein that gives muscle its color
118
What is the purpose of glycogen
allows for anaerobic respiration
119
Are muscle fibers mononucleated or multinucleated
multinucleated
120
What is a sarcomere
functional unit of a myofibril
121
What is a myofibril
contractile unit that extends the length of a myofibril
122
What are t tubules
invaginations of sarcolemma
123
what is the sarcoplasmic reticulum
stores Ca2+, surrounding myofibrils
124
Describe the path of a sarcomere contraction from neural action potential to contraction
- neural action potential
leads to ACh release at a neuromuscular junction
- initiates muscle action potential in the sarcolemma
- AP travels to all parts of the cell in the T tubules
- leads to CA2+ release from the sarcoplasmic reticulum in the sarcoplasm
- initiates sarcomere contraction
125
What is the sliding filament mechanism
Converts ATPs chemical energy to the mechanical energy of motion
126
Actin vs myosin
actin = thin filament
myosin = thick filament
127
Explain the sliding filament mechanism steps
- CA2+ initiates
- opens binding sites on actin
- allows for myosin heads to walk along
- contraction of sarcomere (actin and myosin slide closer)
128
What is the functional (contractile) unit of the muscle cell
sarcomere
129
where are actin and myosin located
within myofibril
130
what structure carries the action potential to all areas of the cell
t tubules
131
What is a tendon
parallel collagen attaches muscle to bone
132
are tendons vascular or avascular
avascular
133
what is a muscle belly
muscle fibers
134
is muscle belly vascular or avascular
vascular
135
what is aponeurosis
flattened sheet like tendon
136
what are the two shapes of tendon
rope-like, aponeurosis
137
what does -ceps mean
head
138
What types of information is included in muscle names
shape, number of heads, length or size of tendon or muscle, location, action
139
Are muscle connective tissues continuous or discontinuous
All continuous
bone to periosteum to tendon to epimysium to perimysium to endomysium
140
How does neurovasculature of muscle travel
Follows the connective tissue to the muscle fiber, typically deep to the muscle
141
What is fascia
Compartment that wraps around groups of muscles and their epimysium, muscles often share similar function or innervation
142
What is a motor unit
all of the muscle fibers associated with one motor neuron (similar to receptive fields)
143
What is the function of small motor units
Precise movements
144
What is the function of large motor units
forceful movements
145
What is an example of a exceptional muscle whose neurovasculature runs superficial to the muscle
serratus anterior
146
Which attachment (proximal or distal) is considered the origin, and which the insertion
Proximal = origin
Distal = insertion
147
Which attachment (proximal or distal) is more stable, and which more movable
Proximal = stable
Distal = movable
148
A muscle that crosses two joints acts on how many joints
2
149
With which connective tissue does a branch of a motor nerve that supplies a muscle fiber course
endomysium (surrounds fiber)
150
What is an isometric muscle contraction
muscle does not change in length, tension is equal to resistance
151
What is the purpose of an isometric muscle contraction
stabilizes joints and maintains posture
152
What is an isotonic contraction
muscle changes length
153
What is a concentric contraction
Tension overcomes resistance, muscle shortens (pick something up)
154
What is an eccentric contraction
Tension slows lengthening, muscle lengthens (lower something down)
155
What is muscle tone / tonic contraction
weak involuntary contractions that do not produce movement (ie holding your head up)
156
What is reflexive contraction
produces automatic movements that are not voluntarily controlled
157
What is a prime mover / agontist muscle
main muscle responsible for producing a specific movement through concentric contraction
158
What is an antagonist muscle
muscle that opposes the action of another muscle through eccentric contraction
159
What is a synergist muscle
may weakly act with the prime mover (concentric contraction) or acting as a fixator for intermediate joint (isometric contraction)
160
What is a fixator muscle
muscle that stabilizes proximal parts of a limb while movements are occurring in distal parts through isometric contraction
