11Gross Anatomy Lect - Shoulder & G.a.s. (665-684)

Front 1

Acromioclavicular joint is a

Back 1

plane joint; sliding, uniaxial

Front 2

Sternoclavicular joint is a

Back 2

saddle joint; biaxial

Front 3

Joint between the humerus and glenoid of the scapula

Back 3

ball and socket joint; multi-axial

Front 4

Back 4

Synovial joints have the following:
Joint cavity
Articular (hyaline) cartilage
Synovial membrane
Articular capsule
Ligaments – reinforce fibrous capsule

Front 5

Back 5

Additional features of synovial joints:
Articular disc
Fat pad
Bursa

Front 6

A bursa is a flattened sac of ___ membrane
A bursa exists between a tendon and a bone to ___

Back 6

-synovial
-minimize friction

Front 7

Synovitis

Back 7

inflammation of a synovial sheath

Front 8

Dislocation of the glenohumeral joint may affect what nerve?

Back 8

axillary n.

Front 9

glenoid labrum

Back 9

lip of fibrocartilage over glenoid fossa

Front 10

pectoral girdle

Back 10

clavicle and scapula

Front 11

Back 11

Front 12

Three synovial joints of the shoulder complex

Back 12

Glenohumeral – ball and socket between
Sternoclavicular - saddle
Acromioclavicular - planar

Front 13

Scapulothoracic joint

Back 13

functional joint of the shoulder complex

Front 14

The only bony attachment of the upper limb to the axial skeleton is at the

Back 14

sternoclavicular joint; saddle with an intra-articular fibrocartilage disc

Front 15

Scapulohumeral Rhythm: Pectoral Girdle & Shoulder Motion

Back 15

There is a 2:1 ratio of glenohumeral to scapulothoracic motion during overhead reaching (flexion and abduction)

When the arm is vertical at the side of the head (180 degrees of flexion or abduction – relative to the thorax) 120 degrees occurs at the glenohumeral joint while 60 degrees occurs at the scapulothoracic joint

Front 16

Back 16

Front 17

The acromioclavicular joint contains a ___ that partially subdivides the articular space

Back 17

small articular disk

Front 18

It is a ___ joint that allows ___ , which occurs when the scapula rotates upward and outward

Back 18

-synovial plane
-gliding motion

Front 19

AC joint is stabalized by ___; composed of

Back 19

-coracoclavicular ligament
-conoid and trapezoid ligaments

Front 20

“AC separation” sometimes referred to as “a separated shoulder” occurs when

Back 20

-if the AC, coracoclavicular (conoid & trapezoid) ligaments all tear
-The scapula separates from the clavicle and falls because of the weight of the upper limb

Front 21

falling directly on the shoulder or on the outstretched limb/elbow may affect what ligament(s)

Back 21

AC and possibly coracoclavicular (conoid & trapezoid) ligaments tear

Front 22

Which ligament is more weak, AC or coracoclavicular ligaments?

Back 22

AC

Front 23

Which joint has the greatest mobility? Type of joint?

Back 23

-glenohumeral
-ball and socket

Front 24

Glenohumeral joint is held together by the tonic activity of the ___ , the fibrocartilage extension of the ___ , joint capsule and reinforcing ligaments.

Back 24

-rotator cuff muscles
-glenoid (glenoid labrum)

Front 25

Subacromial (Subdeltoid) bursa reduces friction between the ___ and the ___

Back 25

-supraspinatus tendon
-coracoacromial arch

Front 26

Scapulohumeral muscles =

Back 26

Intrinsic Shoulder Muscles

Deltoid
Teres major
Muscles of the rotator cuff
Supraspinatus
Infraspinatus
Teres minor
Subscapularis

Front 27

Doctor gives resistance to the patient who is instructed to raise (abduct) his arm. She is also palpating for the contraction of the deltoid muscle. This tests for:

Back 27

deltoid muscle, axillary nerve, and 5th cervical spinal nerve (C5 neurological level).

Front 28

Muscles of the rotator cuff

Back 28

supraspinatus, infraspinatus, teres minor, subscapularis

Front 29

supraspinatus, infraspinatus, and teres minor muscles fuse together as they attach to the 3 facets of the

Back 29

greater tubercle of the humerus

Front 30

the supraspinatus muscle traverses an arch made by the acromion and the ___ on its route to the humerus

Back 30

coracoacromial ligament

Front 31

Suprascapular nerve reaches the supraspinous fossa by traversing the suprascapular notch ___ the cover of the transverse scapular ligament.

Back 31

beneath

Front 32

The suprascapular artery reaches the same area, runs ___ the suprascapular ligament.

Back 32

over

Front 33

To test for integrity of the suprascapular nerve, you ask the patient to

Back 33

abduct the arm from the fully adducted position

Front 34

“Abduction of the humerus at the glenohumeral joint is initiated by the ___. After the shoulder has been abducted to 10-15°, the ___ continues the movement.”

Back 34

-supraspinatus muscle
-deltoid muscle

Front 35

Teres Minor Muscle passes through the

Back 35

quadrangular space

Front 36

A proximal humeral fracture puts this nerve at risk of injury

Back 36

axillary nerve

Front 37

Which of the rotator muscles insert onto the lesser tubercle of the humerus?

Back 37

subscapularis

Front 38

Rotator cuff tears most typically involve the ___; Patient has difficulty ___ the arm overhead and the movement is usually accompanied by pain.

Back 38

-supraspinatus
-abducting or flexing

Front 39

Rotator cuff tears, Drop arm test

Back 39

arm drops as the slightest pressure when abducted

Front 40

Rotator cuff muscles act synergistically with the ___ during flexion and abduction; glenohumeral motion

Back 40

deltoid

Front 41

What muscles are active during overhead movements of the upper limb?

Back 41

rotator cuff muscles

Front 42

Borders of the quadrangular space are:

Back 42

teres minor
teres major
long head of the triceps
humerus

Front 43

What passes through the quadrangular space?

Back 43

Axillary nerve and the posterior circumflex humeral artery

Front 44

Fracture of the surgical neck of the humerus may damage

Back 44

the axillary nerve and posterior circumflex humeral artery

Front 45

Axillary nerve injury will cause ___ atrophy and loss of sensation over the ___ side of the proximal arm

Back 45

-deltoid muscle
-lateral

Front 46

Back 46

Front 47

Intercostal arteries anastomoses with the

Back 47

deep transverse cervical a. (dorsal scapular a.)

Front 48

During surgery or following trauma, arteries may be ligated (tied off) to avoid bleeding.
What enables this to be performed without causing tissue damage from ischemia (lack of blood)?

Back 48

Arterial anastomoses

Front 49

Back 49

Note:
Glenoid labrum
Inferior capsule (note laxity)
Lack of additional support from rotator cuff inferiorly.
Lack of congruency between humerus and glenoid

Front 50

Back 50

Front 51

Biceps Brachii Muscle

Proximal attachment
Short head:
Long head:

Function regarding the shoulder:
Stabilizes ___, weak ___ of the humerus

Back 51

Proximal attachment
Short head: tip of the coracoid process
Long head: supraglenoid tubercle of scapula

-anterior aspect of the shoulder
-flexor

Front 52

___ membrane when humerus is in adduction permits great freedom of movement

Back 52

Redundant synovial

Front 53

Back 53

Glenohumeral ligaments (superior, middle, and inferior) are thickenings of the fibrous joint capsule that strengthen the capsule anteriorly

Front 54

Additional movers of the shoulder…

Back 54

Pectoralis major & minor
Serratus anterior
Coracobrachialis
Triceps longhead