Chapter 9 - Joints Flashcards
1
Q
what is an articulation and what happens here?
A
where 2 bones meet and body movements occur
2
Q
what does the structure of a joint determine?
A
direction
distance of movement (range of motion)
3
Q
what kind of relationship exists between joint mobility and joint stability?
A
inverse relationship (when one goes up the other goes down)
4
Q
what are functional joint classifications based on and what are the 3 classifications?
A
based on joint range of motion
- Synarthrosis
- Amphiarthrosis
- Diarthrosis
5
Q
what are synarthroses?
A
immoveable joints
6
Q
what are amphiarthoses?
A
slightly moveable joints
7
Q
what are diarthroses?
A
freely moveable joints
8
Q
what are structural joint classifications based on and what are the 4 classification?
A
based on anatomical organization of the joint
- fibrous
- cartilaginous
- bony
- synovial
9
Q
name the types of fibrous joints
A
- syndesmosis
- suture
- gomphosis
10
Q
name the type of cartilaginous joints
A
- synchondrosis
- symphysis
11
Q
name the types of bony fusion joints
A
synostosis
12
Q
name the types of synovial joints
A
- ball-and-socket joint
- pivot
- saddle
- condylar (ellipsoidal)
- hinge
- gliding (planar)
13
Q
name the structurally synarthrotic joints
A
- suture
- gomphosis
- synchondrosis
- synostosis
14
Q
name the structurally amphiarthrotic joints
A
- syndesmosis
- symphysis
15
Q
what kind of connections may occur in synarthroses?
A
fibrous or cartilaginous
may fuse and become synostosis
16
Q
what are sutures?
A
short connective tissue fibers that hold the bones together
17
Q
where are sutures found?
A
between bones of the skull
18
Q
where are gomphoses found and how do they stay in place?
A
- between teeth and jaw
- held in place by fibrous periodontal ligament
19
Q
what are synchondroses formed by?
A
2 bones joined together by hyaline cartilage
20
Q
where are synchondroses found?
A
- epiphyseal growth plates of long bones
- connects diaphysis and epiphysis in growing bones. when growth plate closes, hyaline cartilage is replaced with bone and synchondrosis becomes synostosis - between costal cartilage of first rib and manubrium
21
Q
how are synostosis created?
A
- 2 bones, once separated, fuse and boundary between them disappears
- where synchondroses joints that fused
- ossification occurs with age
22
Q
where are synostoses found?
A
- left and right mandible
- left and right frontal bones
- epiphysis and diaphysis of long bones
23
Q
what kind of structural connections may occur at amphiarthroses?
A
fibrous or cartilaginous (tend to be fibrous)
24
Q
what is found in syndesmotic joints?
A
bones connected by ligaments, cords, or a band of fibrous sheets (interosseous membrane)
25
where are syndesmoses found?
- distal tibia-fibula
- interosseous membrane between
- radius and ulna
- tibia and fibula
26
what is found in symphyses?
- end of articulating bones covered by hyaline cartilage
- bones joined by fibrocartilage
- can act as shock absorber or loosen during birth
27
where are symphyses found?
- public symphysis
| - intervertebral joints
28
6 features of synovial joints
- articular cartilage
- joint cavity
- articular capsule
- synovial fluid
- reinforcing ligaments
- nerves and blood vessels
29
describe articular cartilage and their purpose
- (aka hyaline cartilage) covers articulating surfaces of synovial joints
- prevents bones from touching
30
describe joint cavity
joint space that contains synovial fluid
31
describe articular capsule and its purpose
- 2 layers:
- outer fibrous capsule (dense irregular CT)
- inner synovial membrane
- continuous with periosteum
- strengthens the joint so the bones arent pulled apart
32
what makes up the inner layer of the articular capsule?
synovial membrane
33
are epithelium present in the synovial membrane?
no
34
what does the synovial membrane consist of?
- connective tissue (areolar connective tissue & adipose tissue)
- discontinuous layer of cells called synoviocytes (cells of synovial membrane)
35
what are the 2 types of synovial cells and what does each do?
- macrophage-like synovial cells (type A cells)
- remove wear-and-tear debris from synovial fluid
- fibroblastic synovial cells (type B cells)
- produce hyaluronan which acts as a lubricant
36
what does synovial fluid consist of?
- interstitial fluid: filtered from blood plasma diffused from capillaries in synovial membrane
- hyaluronan: released by fibroblastic synovial cells (type B cells)
37
what are the functions of synovial fluid?
- lubricates joints to reduce friction
- provides nutrients and waste disposal
- provides shock absorption
38
what are reinforcing ligaments?
ligaments that reinforce and strengthen the joint
39
what are the accessory structures of synovial joints?
- cartilage
- fat pads
- ligaments
- tendons
- bursae
- synovial tendon sheath
- labrum
40
what does the cartilage of synovial joints consist of and what purpose do they serve?
- fibrocartilage pads
- separate articulating surfaces
- helps cushion certain joint
41
what are fat pads composed of, where are they in the joint, and what purpose do they serve?
- masses of adipose tissue covered by synovial membrane
- superficial to joint capsule
- protect articular cartilages
42
what is the purpose of ligaments?
support and strengthen joints
43
what happens when a ligament is sprained?
they have torn collagen fibers
44
are tendons part of synovial joints?
no
45
where are tendons found and what is their purpose?
- pass across or around a joint
- may limit joint ROM
- provide mechanical support for joint
46
what are bursa(e)? where are they generally found? what is their function?
- small fluid-filled (synovial fluid) sac
- surrounds tendons or sits between tendon and bone
- reduce friction between tissues and cushion movement of tissues against each other
47
what does a bursa sac consist of?
- outer layer: dense connective tissue
| - inner layer: synovial membrane
48
where are bursa(e) located between?
- skin and bones
- tendons and bones
- muscles and bones
- ligaments and bones
49
what is a synovial tendon sheath and where is it found?
- tube-like bursa
| - wraps around a tendon where it crosses bone surface
50
what is the function of synovial tendon sheath?
protects all sides of a tendon from friction as the tendon slides back and forth
51
what is the labrum? where is it located? what is its purpose?
- fibrocartilaginous structure
- attaches to rim of acetabulum and glenoid cavity
- helps to deepen joint socket
52
Gliding (planar) joint- appearance, movement ability, and examples
- flattened or slightly curved surface
- mainly monaxial - limited motion
- surfaces slide across each other
- examples
- intercarpal joints
- intertarsal joints
- acromioclavicular joint
- claviculosternal joints
- vertebrocostal joints
- sacroiliac joint
53
Hinge (ginglymus) joint- appearance, movement ability, and examples
- convex surface on one bone fits into concave surface of another bone
- monaxial - angular motion in 1 plane (flexion/extension)
- examples
- elbow
- knee (modified hinge)
- ankle
- interphalangeal
54
condyloid (ellipsoid) joint- appearance, movement ability, and examples
- oval surface of one bone fits into oval-shapes depression of another
- biaxial - motion in 2 planes
- flexion/extension
- abduction/adduction
- circumduction
- examples
- radiocarpal joint
- midcarpal joint (doesnt circumduct)
- metacarpophalangeal joints (2-5)
- metatarsophalangeal
55
saddle joint- appearance, movement ability, and examples
- saddle-shaped surface of one bone articulates with articular surface of the other
- biaxial
- flexion/extension
- abduction/adduction
- circumduction
- example
- carpometacarpal joint of thumb (trapezium and 1st metacarpal)
56
pivot joint- appearance, movement ability, and examples
- rounded surface of one bone articulates with ring formed party by another bone and party by ligament
- monaxial - rotation
- examples
- atlanto-axial joint
- radio-ulnar joint
57
ball-and-socket joint- appearance, movement ability, and examples
- ball-like surface of one bone rests w/in a cup-like depression of other bone
- triaxial
- flexion/extension/hyperextension
- abduction/adduction
- internal/external rotation
- circumduction
- examples
- shoulder (glenohumeral) joint
- hip joint
58
Name of joint at maxilla/teeth and mandible, type of joint, movement
- alveolar
- synarthrosis (gomphosis)
- no movement
59
Name of joint at temporal bone/mandible, type of joint, movement
- temporalmandibular
- combined gliding joint and hinge diarthrosis
- elevation, depression, and lateral gliding
60
Name of joint at occipital bone/atlas, type of joint, movement
- atlantooccipital
- condylar diarthrosis
- flextion/extension
61
Name of joint between vertebral bodies (C2-L5), type of joint, movement
- intervertebral- separated by intervertebral discs
- amphiarthrosis (symphysis)
- slight movement
62
Name of joint between articular processes in vertebrae, type of joint, movement
- intervertebral
- gliding diarthrosis
- slight flexion/extension
63
Name of joint between L5 body and sacral body, type of joint, movement
- lumbosacral
- amphiarthrosis (symphysis)
- slight movement
64
Name of joint between inferior articular facets of L5 and superior articular facets of sacrum, type of joint, movement
- lumbosacral
- gliding diarthrosis
- slight flexion/extension
65
Name of joint at sacrum/hip bone, type of joint, movement
- sacroiliac
- gliding diarthrosis
- slight movement
66
Name of joint at sacrum/coccyx, type of joint, movement
- sacrococcygeal
- gliding diarthrosis (may fuse)
- slight movement
67
Name of joint at coccygeal bones, type of joint, movement
- synarthrosis (synostosis)
| - no movement
68
Name of joint at bodies of T1-T12 and head of ribs, type of joint, movement
- costovertebral
- gliding diarthrosis
- slight movement
69
Name of joint at transverse processes of T1-T10, type of joint, movement
- costovertebral
- gliding diarthrosis
- slight movement
70
Name of joint at ribs and costal cartilage, type of joint, movement
- synarthrosis (synchondrosis)
| - no movement
71
Name of joint at sternum and 1st costal cartilage, type of joint, movement
- sternocostal (1st)
- synarthrosis (synchrondrosis)
- no movement
72
Name of joint at sternum and costal cartilages 2-7, type of joint, movement
- sternocostal (2-7)
- gliding diarthrosis (may convert to synchrondrosis in elderly individuals)
- slight movement
73
Name of joint at sternum/clavicle, type of joint, movement
- sternoclavicular
- gliding diarthrosis
- protraction/retraction, elevation/depression, slight rotation
74
Name of joint at scapula/clavicle, type of joint, movement
- acromioclavicular
- gliding diarthrosis
- slight movement
75
Name of joint at scapula/humerus, type of joint, movement
- glenohumeral
- ball and socket diarthrosis
- flexion/extension, adduction/abduction, circumduction, rotaion
76
Name of joint at humerus/ulna and humerus/radius, type of joint, movement
- humeroulnar and humeroradial
- hinge diarthrosis
- 1 degree of freedom: flextion/extension
77
Name of joint at ulna/radius, type of joint, movement
- proximal radioulnar
- pivot diarthrosis
- 1 degree of freedom- rotaion
- distal radioulnar
- pivot diarthrosis
- pronation/supination
78
Name of joint at radius/carpal bones, type of joint, movement
- radiocarpal
- condylar diarthrosis
- 2 degrees of freedom: flexion/extension, adduction/abduction (radial/ulnar deviation), circumduction
79
Name of joint at carpal bone to carpal bone, type of joint, movement
- intercarpal
- gliding diarthrosis
- slight movement
80
Name of joint at carpal bone to metacarpal bone 1, type of joint, movement
- carpometacarpal of thumb
- saddle diarthrosis
- flexion/extension, adduction/abduction, circumduction, opposition
81
Name of joint at carpal bone to metacarpal bone 2-5, type of joint, movement
- carpometacarpal
- gliding diarthrosis
- flexion/extension, adduction/abduction, circumduction
82
Name of joint at metacarpal bone to phalanx, type of joint, movement
- metacarpophalangeal
- condylar diarthrosis
- flexion/extension, adduction/abduction, circumduction
83
Name of joint at phalanx/phalanx, type of joint, movement
-interphalangeal
-hinge diarthrosis
flexion/extension
84
Name of joint at sacrum/ilium of hip bone, type of joint, movement
- sacroiliac
- gliding diarthrosis
- slight movement
85
Name of joint at hip bone/hip bone, type of joint, movement
- public symphysis
- amphiarthrosis
- no movement
86
Name of joint at hip bone/femur, type of joint, movement
- hip
- ball and socket diarthrosis
- 3 degrees of freedom
- flexion/extension, adduction/abduction, circumduction, rotation, horizontal flexion/horizontal extension
87
Name of joint at femur/tibia, type of joint, movement
- knee
- complex, functions as hinge
- flexion/extension, limited rotation
88
Name of joint at tibia/fibula, type of joint, movement
- tibiofibular (proximal)
- gliding diarthrosis
- slight movement
- tibiofibular (distal)
- gliding diarthrosis and amphiarthrtic syndesmosis
- slight movement
89
Name of joint at tibia/fibula with talus, type of joint, movement
- talocruralor ankle
- hinge diarthrosis
- flexion/extension (dorsiflexion/plantar flexion)
90
Name of joint at tarsal bone to tarsal bone, type of joint, movement
- intertarsal
- gliding diarthrosis
- slight movement
91
Name of joint at tarsal bone to metatarsal bone, type of joint, movement
- tarsometatarsal
- gliding diarthrosis
- slight movement
92
Name of joint at metatarsal bone to phalanx, type of joint, movement
- metatarsophalangeal
- condylar diarthrosis
- flexion/extension, adduction/abduction
93
Name of joint at phalynx/phalynx, type of joint, movement
- interophalangeal
- hinge diarthrosis
- flexion/extension
94
Name of joint at odontoid process (dens) of C2 and posterior aspect of anterior arch of C1, type of joint, how its held in place
-atlanto-axial
-diarthodial (pivot)
held in place by tansverse ligaments
95
Name of joint at superior articular facets of C2 and inferior articular facets of C1, type of joint
- atlanto-axial
| - diarthrodial (gliding)
96
Where are intervertebral discs found and what do they consist of/
- aka fibrocartilage discs
- found between vertebral bodies of adjacent vertebrae fro C2 to sacrum
- consist of annulus fibrosis and nucleus pulposus
97
describe location and structure of annulus fibrosis and where it's found
- outer layer of fibrocartilage (intervertebral) discs
| - consists of thin external layer of collagen fibers covering overlapping laminae of fibrocartilage
98
describe layout of collagen fibers w/in annulus fibrosis and their function
- w/in each laminae they lie parallel and run in oblique direction
- orthogonally arranged in adjacent layers
- strengthens and resists force from different directions
99
describe location and structure of nucleus pulposus
- inner layer of fibrocartilage (intervertebral) discs
- located in center of annulus fibrosis
- consists of gel-like material
100
what happens to nucleus pulposus with age?
becomes smaller and is partially replaced by fibrocartilage
101
degrees of freedom and actions of vertebral column
- 3 degrees of freedom
- flexion/extension/hyperextension
- lateral flexion
- rotation
102
what happens in a herniated intervertebral disc?
the nucleus pulposus bulges out through the anulus fibrosus
103
anterior longitudinal ligament: location, beginning, and ending
- an intervertebral ligament
- extends between C1 and sacrum
- arises from anterior tubercle of C1
- attaches to anterior aspect of vertebral bodies and intervertebral discs
- attaches to sacral base
- some fibers continue superiorly from anterior tubercle of C1 to basilar part of occipital bone
104
anterior atlantoccipital membrane: location, beginning, ending, reinforced by
- intervertebral ligament
- between anterior margin of foramen magnum and upper border of anterior arch of C1
- reinforced in midline by upward continuation of some fibers from anterior longitudinal ligament
105
posterior longitudinal ligament: location, beginning, and ending
- intervertebral ligament
- inside vertebral canal
- arises from posterior surface of vertebral body of C2
- attaches loosely to posterior aspect of vertebral body and firmly to intervertebral discs
- decends into lumbar spine, narrows, and attaches to posterior aspect of sacrum
106
tectorial membrane: location, what it connects
- intervertebral ligament
- upward continuation of posterior longitudinal ligament
- connects posterior aspect of odontoid process to anterior surface of foramen magnum
107
ligamenta flava location, beginning, and ending
-intervertebral ligament
-connects lamina of adjacent vertebrae
extends from C2 to 1st sacral segement
-extends between C2 lamina and posterior arch of C1
-continues superiorly as posterior atlanto-occipital membrane
-contains lots of elastic fibers
108
posterior atlanto-occipital membrane: location, beginning, and ending
- intervertebral ligament
| - connects superior aspect of posterior arch of C1 to posterior margin of foramen magnum
109
ligamentum nuchae: location, beginning, and ending
- intervertebral ligament
- midline ligament that entends from EOP and external occipital crest to spinous process of C7
- attaches to posterior tubercle of C1 and spinous processes of C2-C7
- inferior to C7- continuous with supraspinous ligament
- contains lots of elastic fibers
110
supraspinous ligament: location, beginning, and ending
- intervertebral ligament
- connects tips of spinous proesses of adjacent vertebrae from C7 to sacrum
- superior to C7- continuous with nuchal ligament
111
interspinous ligament: location, beginning, and ending
- intervertebral ligament
- connects spinous processes of adjacent vertebrae
- from C2 spinous process to 1st sacral segment
- blends w/ ligamenta flava anteriorly and supraspinous ligament posteriorly
112
4 structures of the shoulder complex
- sternum (manubrium)
- clavicle
- scapula
- humerus
113
2 structures of the shoulder girdle
- clavicle
| - scapula
114
4 articulations of shoulder complex
- glenohumeral joint
- sternoclavicular joint
- acromioclavicular joint
- scapulotheoracic "joint"
115
restriction at any joint of the shoulder complex will affect what?
movement of upper extremity
116
which is the most freely movable joint in the body and how many degrees of freedom does it have?
- glenohumeral
| - 3 degrees of freedom
117
how deep is the glenoid cavity and what helps to increase this?
- less than 1/2 that of the humeral head
| - increased by glenoid labrum (fibrocartilage)
118
structure of the glenoid labrum?
fibrous cartilage attached to rim of glenoid cavity
119
functions of glenoid labrum
- deepen shoulder socket for increased stability of shoulder joint
- attachment site for structures around joint
- ligaments: attach at key locations and help hold joint together
- tendon of long head of biceps brachii: attaches at superior aspect and to supragenoid tubercle
120
what could happen if a shoulder injury tears ligaments or biceps tendon
glenoid labrum may be pulled of rim of glenoid cavity
121
where does the articular capsule of the shoulder attach?
to circumference of glenoid cavity just superficial to glenoid labrum and partially to labrum
122
synovial membrane of glenohumeral joint: attachment, insertion, and where it extends from
- attaches to inner surface of capsule
- inserts on anatomical neck of humerus
- extends from margin of glenoid cavity
123
what supports the glenohumeral joint?
rotator cuff musculature
124
which muscles make up the rotator cuff?
SItS muscles
- supraspinatus
- infraspinatus
- teres minor
- subscapularis
125
function of the tendons of the rotator cuff muscles?
- encircle joint
| - stabilize joint- hold humeral head in glenoid cavity
126
4 bursae of the shoulder
- subacromial bursa
- subdeltoid bursa
- subcoracoid bursa
- subscapular bursa
127
where does the tendon of the long head of the biceps brachii travel?
passes through intertubercular (bicipital) groove as it travels proximally to attach to supraglenoid tubercle
128
3 bones of the elbow complex
- humerus
- ulna
- radius
129
articulations of the elbow complex
- humeroulnar joint
- humeroradial joint
- proximal radioulnar joint (may not be considered part of elbow joint b/c articulation is btwn proximal radius and ulna, not w/ humerus)
130
where does most of the contact at the elbow joint occur?
btwn humerus and ulna
131
how many joint capsules enclose the 3 joints of the elbow complex?
1 joint capsule
132
what does the humeroulnar joint consist of?
articulation btwn trochlea of distal humerus and trochlear notch of the proximal ulna
133
what does the humeroradial joint consist of?
articulartion between proximal surface of radius and capitulum of the distal humerus
134
in the proximal radioulnar joint which bone moves during supination/pronation? what are the position of the bones during these movements?
- radius pivots around fixed ulna
- supination: radius and ulna are parallel
- pronation: radius crosses over ulna
135
which ligament binds the radius and ulna together and allows for rotation?
annular ligament
136
what connects the shafts of the radius and ulna
interosseous membrane
137
2 articulations of the wrist
- radiocarpal joint
| - midcarpal joint
138
what forms the radiocarpal joint?
- distal concave surface of radius
- radioulnar disc (articular disc of radiocarpal joint)
- scaphoid
- lunate
- triquetrum (at full ulnar deviation, its medial surface contacts articular disc)
139
what separates the ulna from the carpal bones?
radioulnar disc
140
what is the radioulnar disc and what does it attach to?
- fibrocartilaginous disc
| - attaches to ulnar notch of radius
141
what is are the functions of the radioulnar disc?
- separates distal surface of ulna from triquetrum and lunate
- absorbs shock
142
what forms the midcarpal joint?
- proximal and distal rows of carpal bones
- scaphoid w/ trapezium, trapezoid, capitate
- lunate w/ capitate and hamate
- triquetrum w/ hamate
143
what may be considered synonymous with the transverse carpal ligament?
flexor retinaculum
144
3 segments of flexor retinaculum
- proximal: fascia (palmar carpal ligament)
- central: middle (transverse carpal ligament)
- distal: aponeurosis (palmar aponeurosis)
145
palmar carpal ligament: formed by, blends with, crosses over
- aka volar carpal ligament
- formed by thickening of the antebrachial fascia of forearm
- distal fibers blend w/ transverse carpal ligament
- crosses over flexor muscles
146
what is the structure of the transverse carpal ligament?
strong fibrous band of fibrous connective tissue
147
what does the palmar carpal ligament attach to?
- radial styloid process
| - ulnar styloid process
148
what does the transverse carpal ligament attach to?
- proximally: palmar carpal ligament
- medially: pisiform, hook of the hamate
- laterally: scaphoid, trapezium
149
what does the transverse carpal ligament form over the bones of the wrist
arches over carpal bones forming carpal tunnel
150
what arches to form the carpal tunnel
transverse carpal ligament
151
what is the carpal tunnel and what does it connect?
- fibro-osseous pathway on palmar aspect of wrist
| - connects anterior compartment of distal forearm w/ mid-palmar space of hand
152
what passed through the carpal tunnel?
- median nerve
- tendons
- flexor digitorum superficialis
- flexor digitorum profundus
- flexor pollicis longus
153
what is the palmar aponeurosis?
thick broad flat tendon overlying central compartment of palm
154
attachments of palmar aponeurosis
- proximally: transverse carpal ligament then to palmaris longus
- anteriorly: overlying skin at the skin creases of the palm and bases of the digits
- posteriorly: invests into underlying muscle of the hand
155
what does the palmar aponeurosis overlie distally/
continues as 4 slips overlying flexor tendons of digits 2-5
156
function of palmar aponeurosis
stabilizes the skin of the palm
157
what articulates at hip joint?
acetabulum of innominate bone and head of femur?
158
what is the carpal tunnel and what does it connect?
- fibro-osseous pathway on palmar aspect of wrist
| - connects anterior compartment of distal forearm w/ mid-palmar space of hand
159
what passed through the carpal tunnel?
- median nerve
- tendons
- flexor digitorum superficialis
- flexor digitorum profundus
- flexor pollicis longus
160
what is the palmar aponeurosis?
thick broad flat tendon overlying central compartment of palm
161
attachments of palmar aponeurosis
- proximally: transverse carpal ligament then to palmaris longus
- anteriorly: overlying skin at the skin creases of the palm and bases of the digits
- posteriorly: invests into underlying muscle of the hand
162
what does the palmar aponeurosis overlie distally/
continues as 4 slips overlying flexor tendons of digits 2-5
163
function of palmar aponeurosis
stabilizes the skin of the palm
164
what articulates at hip joint?
acetabulum of innominate bone and head of femur?
165
what deepens the hip socket?
acetabular labrum
166
what is the lunate surface?
- smooth crescent-shaped articular surface of acetabulum
- surrounds acetabular fossa
- not present inferiorly at acetabular notch
- covered by hyaline cartilage
167
what is the acetabular fossa?
- deep non-articular circular depression of acetabulum
- not part of articulation
- occupied by fat pad at ligamentum teres
168
what is the acetabular labrum?
fibrocartilage attached to rim of acetabulum expect at acetabular notch
169
what is the acetabular notch?
- notch in inferior margin of acetabulum
| - continuous with acetabular fossa
170
what is the transverse acetabular ligament?
- binds to ends of acetabular labrum at acetabular notch
| - crosses acetabular notch to form a foramen through which blood vessels and nerves pass
171
what is the round ligament also known as?
- ligamentum capitis femoris
| - ligamentum teres
172
where does the round ligament originate and attach?
- originates along the transverse acetabular ligament
| - attaches to fovea capitis
173
what does the artery of the round ligament do?
passes through round ligament to supply blood to the head of the femur
174
bones of the knee joint
- distal femur
- proximal tibia
- patella
175
articulations of the knee joint
- tibiofemoral joint
| - patellofemoral joint
176
how many degrees of freedom are in the tibiofemoral joint?
-2 degrees of freedom
-modified hinge
-flexion/extension
internal/external rotation
177
what are menisci and where are they located?
- 2 cresent-shaped fibrocartilaginous discs between the femur and tibia (tibiofemoral joint), w/in capsule of the knee joint
- provides sock absorption
178
what kind of joint is the patellofemoral joint and what movements does it allow?
- gliding joint
- distally glides with knee flexion
- proximally glides with knee extension
179
what does the patella do for the quadriceps muscle?
increases the moment arm
180
what are the 2 classifications of ligaments at the knee joint?
- extracapsular ligaments
| - intracapsular ligaments
181
what are the extracapsular ligaments and what is their purpose?
- medial/lateral collateral ligaments
| - provide stability in coronal plane
182
what are the intracapsular ligaments and what is their purpose?
- anterior/posterior cruciate ligaments
| - provide stability in the sagittal plane (limit anterior and posterior gliding movements
183
describe the proximal attachment of the ACL
- posteromedial aspect of lateral femoral condyle in the intercondylar fossa
- runs distally, medially, and anteriorly
184
describe the distal attachment of the ACL
anterior aspect of intercondylar eminence of tibia
185
how do the ACL and PCL interact
ACL passes lateral to PCL and curves around it
186
describe the proximal attachment of the PCL
- anterolateral aspect of medial femoral condyle in intercondylar fossa
- runs distally, laterally, posteriorly
187
describe the distal attachment of the PCL
posterior aspect of intercondylar eminence of tibia
188
describe appearance of medial collateral ligament
-broad, flat band that widens by the distal attachment into anterior and posterior bands
189
describe the proximal attachment of medial collateral ligament
posterior aspect of medial femoral epicondyle
190
describe distal attachment of medial collateral ligament
- anterior band: proximal medial aspect of tibia
| - posterior band: blends into the capsule of the knee joint and fusing to the medial edge of the medial meniscus
191
describe the proximal attachment of the lateral collateral ligament
lateral femoral epicondyle
192
describe the distal attachment of the lateral collateral ligament
head of the fibula
193
describe the appearance of the wedge shape of the menisci and the purpose it serves
- peripheral margins are wider than inner margins
- superior surface is concave and articulates w/ femoral condyles
- wedge shape serves to deepen the articular surface of tibia
194
describe shape of the medial and lateral menisci
- medial is semicircular shape
| - lateral is nearly circular (covers more of the tibial articular surface than medial)
195
where does the anterior horn of the medial meniscus attach?
to the anterior intercondylar area of the tibia
196
where does the posterior horn of the medial meniscus attach?
to the posterior intercondylar area of the tibia
197
where does the anterior horn of the lateral meniscus attach?
to the anterior intercondylar area of the tibia
198
where does the posterior horn of the lateral meniscus attach?
to the posterior intercondylar area of the tibia
199
what does the ACL prevent during knee movement?
anterior sliding of tibia
200
what does the PCL prevent during knee movement?
posterior sliding of tibia
