Exam #3 (Lecture 10; Joints-Coracoacromial arch)

Question 1

clavicle like a strut holding the scapula:

Answer 1

Sternoclavicular

Question 2

firmly attaches the scapula to clavicle:

Answer 2

acromioclavicular

Question 3

not a true anatomic joint
an interface between bones
movements are linked to the movements at the SC and AC
the position of the scapula provides the base for the GH joint

Answer 3

scapulothoracic

Question 4

most distal and mobile portion of the whole complex

Answer 4

glenohumeral

Question 5

what are 3 features of the shoulder complex? (3)

Answer 5

series of kinematic links
cooperate to maximize ROM
weakened, painful or unstable link decreases the effectiveness of the entire UE

Question 6

elevation: _______ slide
depression: ________ slide

Answer 6

superior
inferior

Question 7

protraction: medial border slides _______
retraction: medial border slides _________

Answer 7

ant/lat
post/med

Question 8

upward rotation: inferior angle rotates _______ direction. glenoid fossa faces _______. UE ________
downward rotation: inferior angle rotates ________ direction. UE ________

Answer 8

superior-lateral direction. upward. elevation

inferior-medial direction. downward

Question 9

what 3 things connect at the SC joint?

Answer 9

medial end of clavicle
clavicular facet on sternum
superior border of cartilage of the first rib

Question 10

what links the axial and appendicular skelton?

Answer 10

basilar joint of UE (base of clavicle)

Question 11

the SC joint is ____ attached and allows _____ ROM

Answer 11

firmly
large

Question 12

what is the shape of the SC joint?

Answer 12

irregular saddle shaped

Question 13

longitudinal diameters:
_____ plane between _______ & _______ points

Answer 13

frontal plane
superior and inferior points

Question 14

transverse diameters:
______ plane between _______ & _______ points

Answer 14

horizontal plane
anterior and posterior points

Question 15

what ligaments attach at the SC joint?

Answer 15

anterior and posterior SC ligaments (reinforces capsule)
interclavicle ligament
costoclavicular ligament
articular disc (50% only)

Question 16

what muscles cross across the SC joint?

Answer 16

SCM
sternothyroid
sternohyoid
subclavius muscles

Question 17

how many DOF for SC joint?
what are the 3 kinematic motions of SC joint?

Answer 17

3 - sagittal, frontal, horizontal
elevates/depresses, protracts/retracts, rotates (posterior)

Question 18

what is the goal of the SC joint?

Answer 18

to place scapula in optimal position for head of humerus

Question 19

elevation and depression osteokinematics of SC joint:

parallel to _______ plane
axis -
______ degrees elevation
______ degrees degression
_______ motion is similar in scapula

Answer 19

frontal
near anterior-posterior
35-45
10
clavicular

Question 20

elevation and depression arthrokinematics of SC joint:

along _____ diameter

elevation of clavicle:
- convex surface rolls _____ slides _____
- ______ ligament stretches - limits motion

depression of clavicle:
- convex surface rolls ______ slides ________
- _______ ligament/_______ portion of capsule stretches

Answer 20

longitudinal
superiorly; inferiorly
Costoclavicular
inferiorly; superiorly
interclavicular; superior

Question 21

protraction and retraction osteokinematics of SC joint:

occurs parallel to _____ plane
axis:
_______ degrees each direction
associated with _______

Answer 21

horizontal
vertical
15-30
scapula

Question 22

protraction and retraction arthrokinematics of SC joint:

occurs along _______ diameter

retraction:
- concave surface of clavicle rolls and slides ______ on convex surface of sternum
- stretches ________ ligament and ______ capsule

protraction:
occurs in _____ direction
stretches ________ ligament and ____ capsule
involves reaching ______

Answer 22

transverse

posteriorly
anterior CC ligament and anterior

anterior
posterior CC ligament and posterior
forward

Question 23

rotation osteokinematics of SC joint:

rotates around _____ axis
UE elevation: posterior rotation ______ degrees

Answer 23

longitudinal
20-35

Question 24

rotation arthrokinematics of SC joint:

rotation cannot occur without ______ and ______

Answer 24

flexion and abduction

Question 25

what two things connect at AC joint?

Answer 25

lateral end of clavicle acromion of scapula

Question 26

what direction does the clavicular facet face on the acromion?

Answer 26

medial and slightly superior

Question 27

what is the capsule of AC joint reinforced by?

Answer 27

superior and inferior AC ligaments

Question 28

what two ligaments make up the coracoclavicular ligament?

Answer 28

trapezoid ligament conoid ligament - coracoid process to clavicle

Question 29

what type of motion happens at the AC joint?

Answer 29

subtle motions optimize mobility and fit between scap and thorax

Question 30

how many DOF does AC joint have?

Answer 30

3 upward/downward rotation, internal/external rotation, anterior/posterior tilting

Question 31

upward rotation of scapula at AC: swings ____ and _______ relative to end of clavicle up to _____ degrees contributes significantly to _______ motion

Answer 31

upward and outward 30 scapulothoracic

Question 32

what are rotational adjustment motions of the AC joint?

Answer 32

pivoting or twisting type motions of the scapula around lateral end of the clavicle optimally align scapula against the thorax

Question 33

what motion of the AC joint is happening in the horizontal plane? what axis is it?

Answer 33

internal rotation (also protraction) of glenoid fossa (and external rotation) vertical axis

Question 34

what motion of the AC joint is happening in the sagittal plane? what axis is it?

Answer 34

anterior tilting (elevation) or reverse: posterior tilting (depression) medial-lateral axis

Question 35

what would happen without adjustments of the AC joint?

Answer 35

the scapula would have to follow the clavicle exactly and could not adjust the thorax

Question 36

what joint is not true joint with no direct contact?

Answer 36

scapulothoracic joint

Question 37

the scapulothoracic joint is separated by what muscles?

Answer 37

subscapularis serratus anterior erector spinae

Question 38

where does the scapula sit?

Answer 38

between 2nd and 7th ribs medial border 6 cm lateral to spine

Question 39

scapulothoracic joint degrees: - anterior tilt: - upward rotation: - internal rotation:

Answer 39

10 degrees 5-10 degrees 30-40 degrees

Question 40

scapulothoracic elevation is a summation of what?

Answer 40

elevation at the SC joint and downward rotation at AC joint

Question 41

in order to have protraction/retraction of ST joint, what summation must occur?

Answer 41

summation of horizontal motions at both AC (internal rotation) and SC (protraction) protracting clavicle around SC joint, SC varies the amount of internal rotation

Question 42

scapulothoracic upward rotation is a summation of what? full ____ degrees of upward rotation

Answer 42

elevation at the SC joint upward rotation at AC joint 60 degrees

Question 43

general features of what joint? large convex head, shallow concavity - glenoid fossa

Answer 43

glenohumeral joint

Question 44

why is the fibrous capsule of the GH joint loose fitting, thin and expandable?

Answer 44

to allow for mobility which is reinforced by external ligaments

Question 45

what is the axillary pouch in GH joint?

Answer 45

interior portion capsule slackened

Question 46

what is the primary stability in the GH joint? active forces produced by? what crosses superiorly over head of humerus?

Answer 46

passive tendon within embedded ligaments active forces produced by local muscles specifically rotator cuff LBB crosses superiorly over head of humerus

Question 47

- fibrous connective tissue, interlacing collagen fibers - thickening of capsule, complex bands - limits extremes of rotation and translation - help keep a negative intra-articular pressure in GH joint

Answer 47

glenohumeral capsular ligaments

Question 48

superior GH capsular ligament resists:

Answer 48

resists ER/inferior and anterior translations

Question 49

what does the middle GH capsular ligament do? slack in? blends with?

Answer 49

stabilizes most motions esp anterior restraint in 45-90 abd and extremes of ER slack in IR blends with subscap

Question 50

what does the inferior GH capsular ligament support? resist? how many portions? taught in?

Answer 50

supports suspended humeral head resists inf/anterior posterior translations 3 portions (anterior, posterior, axillary pouch), taught in 90 deg abd hammock like

Question 51

what is the strongest/thickest portions of the capsule? primary ligamentous restraint to? what motions are esp stressful?

Answer 51

anterior anterior translation abd and ER with forceful dynamic activities

Question 52

where is the coracohumeral ligament?

Answer 52

coracoid process to greater tubercle

Question 53

coracohumeral ligament blends with?

Answer 53

superior capsule and supraspinatus tendon

Question 54

coracohumeral ligament taut in? restraint what?

Answer 54

taut in anatomical position restraint inferior translation and ER humeral head

Question 55

what forms the coracoacromial arch?

Answer 55

coracoacromial ligament and acromion process

Question 56

what is under the coracoacromial arch?

Answer 56

subacromial space between arch and humeral head

Question 57

what does the coracoacromial arch and bursa contain?

Answer 57

supraspinatus muscle and tendon, subacromial bursa, LHB, superior capsule

Question 58

what impacts the height of subacromial space?

Answer 58

GH arthrokinematics and scapular motion

Question 59

what must the the critical minimum heights be to maintain a lack of compression of contents in subacromial space at: - 20 deg abd: - 85 deg abd: - 150 deg abd:

Answer 59

7.5 mm 2.6 mm 5 mm * more space height is needed as you abduct/adduct arm. least amount of space needed is around 90 deg abd

Question 60

what degree range has the greatest potential for supraspinatus compression?

Answer 60

35-70 deg

Question 61

what is adhesive capsulitis? what does it limit?

Answer 61

excessive thickening or stiffness in ICL limits inferior slide of humeral head

Question 62

in adhesive capsulitis, a superior roll leads to what? how many degrees does it roll before any slide happens?

Answer 62

jamming of the humeral head against coracoacromial arch 22 deg

Question 63

what is impingement syndrome? abrasion may damage what?

Answer 63

unnatural and repeated compression. repeated compression may lead to this abrasion may damage the SS tendon, subacromial bursa, LHB tendon or superior parts of capsule