lecture 6: the shoulder complex Flashcards
1
Q
what is the shoulder complex made up of
A
clavicle , scap , humerus
2
Q
what are the 4 joints that make up the shoulder complex
A
GH joint
SC joint
AC joint
ST joint
3
Q
how much motion of the shoulder complex is at the GH joint and ST joint
A
2/3 at GH
1/3 at ST
4
Q
what is the normal ROM of the shoulder
A
180°
5
Q
_____ stabilization is an active force that provides greater control than passive
A
dynamic
6
Q
what occurs ipsilaterally with shoulder elevation
A
upper thoracic rotation
7
Q
what is the only structural attachement between axial skeleton and the shoulder
A
sternoclavicular joint
8
Q
what are the 3 degrees of freedom at the SC joint
A
elevation/depressoin
protraction /retraction
anterior/ posterior rotation
9
Q
elevation/ depression (of the SC) happen between the ___ and ___
A
disc and clavicle
10
Q
protraction/ retraction(of the SC) happen between the ___ and ___
A
disc and manubrium
11
Q
anterior/posterior rotation (of the SC) happen between the ___ and ___
A
clavicle and 1st rub costocartilage
12
Q
the articulation of the SC joint is what
A
2 plane synovial joint
13
Q
the disc of the SC joint increases ___ and absorbs ___
A
congruence
forces
14
Q
The SC joint creates 2 seperate cavities and acts as a ___ point during motion
A
pivot
15
Q
during elevation / depression (at the SC joint) the clavicle ___ and ___ on the disc
A
rolls and glides
16
Q
during protraction/retraction (of the SC joint) the sc ___ and ___ roll and slide on the ___
A
disc and clavicle
manubrium
17
Q
which ligaments of the SC ligaments both limit A/P translation : posterior is primary
A
anterior and posterior SC ligament
18
Q
the costoclavicular ligament limit ___ of the ___ clavicle
A
elevation
lateral
19
Q
the anterior costoclavicular lig fibers run ___ and the posterior fibers run ____
A
laterally
medially
20
Q
which ligament of the SC ligaments resist excessive depression of clavicle : and superior gliding of the clavicle on manubrium
A
interclavicular ligament
21
Q
during elevation of the SC joint the ___ end of the clavicle moves upward
A
lateral
upward
22
Q
during SC elevation the medial end rolls ___ and slides ____ on the sternun
A
medial
superiorly
inferiorly
23
Q
during SC protraction the lateral clavicle moves ___ in the ___ plane
A
lateral
anteriorly
transverse
24
Q
during protraction of the SC joint the medial clavicel does what on the sternum
A
rolls and slides anteriorly
25
during depression of the SC joint the lateral end of the clavicle moves___
downwards
26
during depression of the SC joint the medial end of the clavicle does what
rolls inferiorly and slides superiorly
27
during retraction of the SC joint the lateral clavicle moves ___
posteriorly
28
during retraction of the SC joint the medial clavicle does what
rolls and slides posteriorly
29
what joint structure attaches the scapula to lateral clavicle
acromioclavicular joint
30
the AC joint is a ____ synovial joint with ___- DOF
plane
3
31
the AC joint allows the scapula to rotate during arm movement which ___ UE motion
increases
32
is the AC capsule strong or weak
weak
33
is the superior or inferior AC ligament stronger
superior
34
which ligament of the AC joint firmly unites clavicle and scapula
coracoclavicular lig
35
what 2 other ligaments make up the coracoclavicular lig of the AC joint
conoid and trapezoid lig
36
what does the conoid lig resist
inferior forces
37
what does the trapezoid lig resist
posterior translation
38
there is a coupled ____ clavicle rotation and scapula ____ rotation during arm elevation
posterior
upward
39
internal and external rotation(20-35°) of the AC joint occurs around the ___ axis
vertical
40
anterior and posterior tilting (20-40°) of the AC joint occurs around the ___ axis
oblique coronal
41
upward (30°) and downward (17°) rotation of the AC joint occurs around the ___ axis
oblique AP
42
is the AC joint stable ?
not rea;;t
43
is the AC joint susceptible to trauma and degenerative changes
yes
44
what is the most common trauma for the AC joint
contact sport or falls on shoulder with arm adducted
45
what joint is formed by anterior surface of scapula with throax
scapulothoracic joint
46
T/F: the ST joint is a true joint
false
47
the scapula rest from midline between ribs ___-___
2-7
48
what is the resting position of the scapula
internally rotated
tilted anteriorly
upwardly rotated
49
how many degrees of ST joint is required to upwardly rotate during arm elevation
60
50
if you have excessive internal rotation of the ST joint what is that called
scapular winging
51
what happens at the scapula during shoulder flexion/abduction
protraction
elevation
upward rotation
52
what happens at the SC joint during shoulder flexion / abduction
protraction (clavicle rolls anterior , slides anterior on manubrium )
posterior rotation w/ elevation (inferior slide , superior roll at the disc)
53
what happens at the AC joint during shoulder flexion / abduction
upward rotation (scap/ acromion in relation to clavicle)
54
what happens at the scapular during shoulder lowering / adduction
retraction
depression
downward rotation
55
during shoulder lowering / adduction , the SC joint does retraction , depression and anterior rotation ... what happens at the SC joint during retraction
clavicle rolls posterior , glides posterior on manubrium
56
during shoulder lowering / adduction , the SC joint does retraction , depression and anterior rotation ... what happens at the SC joint during anterior rotation (to neutral) w/ depression
superior slide and inferior roll at the disc
57
what happens at the AC joint during shoulder lowering/ adduction
downward rotation (scapula/ acromion in relation with clavicle)
58
what provides stability for the ST joint
structures of the AC and SC joint
59
ST joint is a premier example of a ____ stabilizer
dynamic
60
what kind of joint is the glenohumeral joint
ball and socket synovial joint
61
how many DOF does the GH joint have
3 rotary and 3 translatory
62
is the humeral head or glenoid fossa bigger
humeral head
63
which motions of the scapula will influence the GH
any motion
64
the proximal surface of the GH is shallow ___
concavity
65
the proximal surface of the GH can be ____ or ____
retroverted or anteverted
66
the proximal surface of the GH is the ___ ___ of scpaula
glenoid fossa
67
the distal surface of the GH joint is what
the humeral head
68
what is the angle of inclincation of the distal surface of the GH
130-150°
69
what is the angle of torsion of the distal surface of the GH joint
30°
70
what does the glenoid labrum enhance
fossa concavity
71
the glenoid labrum serves as an attachment site for GH ____ and tendon of what muscle
ligaments
long head of biceps
72
what functions to resist humeral head translation , protect bondy edges of fossa, minimize GH joint friction and dissipate joint contact forces
glenoid labrum
73
the capsule of the GH tightens with ____ and ____
abduction and lateral rotation
74
how much distraction is available at the GH capsules during loose packed position
> 2.5 cm
75
the Gh capsule is vulnerable to ____ dislocations
anterior
76
the superior GH lig resits ___ and ___ translations of humeral head at 0° of abduction
ant and inferior
77
which GH ligaments prevents any translation of humeral head from 0-60° of abduction
middle Gh lig
78
the inferior GH ligaments complex is made of of how many components
3 (anterior , posterior and axillary pouch)
79
what does the anterior component of the inferior Gh lig complex prevent
prevents ant/inf translation (abd/ER)
80
what does the posterior component of the inferior Gh lig complex prevent
prevents post/inf translation (abd / IR)
81
what does the axillary pouch component of the inferior Gh lig complex prevent
prevents inf translation (abd)
82
what forms the tunnel for the long head of the biceps to pass thru
coracohumeral lig
83
how many bands does the coracohumeral lig have
2
84
which band of the coracohumeral ligeamnt is at the base of the coracoid to edge of supraspinatus tendon and greater tubercle
first band
85
which band of the coracohumeral ligeamnt is at the base of the coracoid into subscapularis and less tubercle
second band
86
what forms the vault over the humeral head
coracoid , acromion , and coracoacromnial lig
87
what contains subacromial bursa, rotator cuff tendons , and tednon of long head of biceps
subacromial space
88
the coracoacromial arch protects subacromial structures and prevents ___ dislocation of the ___
superior
humerus
89
the coracoacrominal arch can be an area of impingement with ___ and a narrowed joint space
supraspinatus
90
how many degrees of flexion and extension does the GH joint have and around what axis
flexion - 120
extension -50
coronal axis
91
medial and laterla rotation of the GH joint is around what axis
long
92
abduction of the Gh joint is limited when in neutral or medial rotation by what
greater tub
93
how mnay degreees of abduction and adduction is at the GH joint and around what axis
90-120
AP axis
94
during elevation of the GH the humeral head slides ___ and rolls ___
inferiorly
superior
95
a tight GH capsule can causes the shirting of the humeral head during motion or limit motion AKA ___
inferior slide
96
where does gravity pull the arm
inferiorly
97
if the arm is loaded what contracts
supraspinatus
98
when the arm is loaded there is an ____ inferior subluxation with ___- rotator cuff function
increase
decrease
99
during dynamic stabilization of the GH joint what muscle is the prime movers for abduction and flexion
deltoids
100
force vectors of the middle delt are larger ____ rather then ____
parallel
perpendicular
101
what muscle does the deltoid need synergisitc help from to produce desired rotation of humeral head
rotator cuff
102
the .I.T.S perpendicular force component causes some ___ of the humerus but also compresses head into _____ fossa
rotation
glenoid
103
the parallel force component (Fx) of the I.T.S muscles offsets superior translatory force from deltoid by pulling the humeral head ____
inferiorly
104
what muscles help with lateral rotation to clear the greater tubercle for the GH joint
infraspinatus and teres minor
105
which muscle has a large rotary component with large moment arm for adbuction of the GH joint
supraspinatus
106
what ligament runs from the greater and lesser tubercles
transverse humeral ligament
107
the long head of the biceps can contribute to both ____ and ____ of the shoudler
flexion and abduction
108
what muscles helos reinforce the GH joint , centering the head and reducing vertical and anterior shear
LHoB
109
the LHoB may also tighten what
the labrum
110
overal the dynamic stabilization at any point of ROM of the GH joint is infulenced by
1. force generated by ___ ____
2. force of ____
3. force created by ______ _____
4.articular surface geometry
5. _____ capsuloligamentous forces
6. joint ____ forces
primary movers
gravity
muscular stabilizer
passive
reaction
111
all forces of the GH compress the humeral head into the ___ ____
glenoid fossa
112
greatest shear forces of the GH joint occur between how many degrees
30-60° of elevation
113
which rotator cuff tendon is most vulnerable
supraspinatus
114
what kind of tears of common in people over 60
RCT
115
if someone has a rotator cuff tear then they will have pain between what degrees
60-120° (painful arch)
116
what motion of the shoulder distributes motion between 4 joints , permitting more ROM with more stability
scapulohumeral motion
117
the scapulohumeral motion maintains _____ ____ in optimal position for humeral head for better joint ____ and decreased ___
glenoid fossa
congruency
shear
118
the scapulohumeral motion maintains good length tension of humeral muscles preventing ____ insufficiency as the scapula rotates up
active
119
the scaplohumeral rhythm has first ___ of aduction or___ of flexion
30°
60°
120
in the initial phase of scapulohumeral rhythm does the Gh or ST move more
GH mostly
121
during the motion of ST moving 60° what happens at the SC and AC joint
clavicualr elevation at SC
posterior clavicular rotation at AC
122
the motion during ST motion of 60° causes clavicular elevation at the SC , which muscles upwardly rotate the scapula
trapz and SA
123
the motion during ST motion of 60° causes clavicular elevation at the SC , which ligament becomes taut
costoclavicular
124
the motion during ST motion of 60° causes posterior clavicular rotation at AC ,, what happens at the lateral end of the clavicle
it rolls up
125
the motion during ST motion of 60° causes posterior clavicular rotation at AC ,, which ligaments become taut and what does it prevent
coracoclavicualr (conoid and trapezoid) and costoclavicular lig become taut and prevents more elevation
126
for ST upward rotation to occur there has to be a force couple of what muscles
upper trap , lower trap and SA
127
what muscles are a force couple for ST upward rotation and also produce and control tipping and rotation during elevation
traps and SA
128
