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Flashcards in The Shoulder Deck (59):
1

What makes up the shoulder?

The pectoral, scapula and lateral supraclavicular regions

2

What makes up the pectoral girdle?

Sternum, clavicle and scapula

3

What is the role of the pectoral girdle?

Very mobile, bony ring to keep arm away from body so it has a great range of movement

4

What is the pectoral girdle like posteriorly?

It is incomplete as the scapula doesn't articulate with the vertebral column via bone but does so by muscle

5

What is the pectoral girdle like anteriorly?

The clavicle articulates with the axial skeleton

6

Where do the axial and appendicular skeleton articulate?

At the sternoclavicular joint between the manubrium of the sternum and the clavicle

7

What is the shape of the clavicle and why?

S shaped as it gives it compressibility and resilience

8

Where is the clavicle? (where does it end)

Anterior bone, overlies 1st rib and ends at the acromioclavicular joint

9

Where/what is the acromion?

Lateral bone of the scapula at the end of the spine, runs posteriorly for muscles to attach to, top of glenohumeral joint

10

What are some features of the scapula?

Posterior, triangle shaped, glenoid cavity with glenohumeral joint, muscle attachment bone, overlies the rib cage posteriorly

11

What is a clavicle fracture caused by?

Direct or indirect force, force of falling onto the hand travels up the bones in forearm and arm to reach the final clavicle bone.

12

What movements occur in a clavicle fracture?

Weight of the arm drags the lateral fragment of the clavicle inferiorly and the sternocleidomastoid pulls the medial fragment superiorly

13

What positional change can be seen from a clavicle fracture?

Lateral side is lower whilst medial side is higher pushing skin up as bone is very superficial anyway, also arm may be a little bit lower

14

What is the sternocleidomastoid muscle?

Anterior muscle in the neck, at the sternum-clavicle-mastoid process joint.

15

Who most commonly has clavicle fractures? and why

Makes up 2-5% of adult fractures but more so in children as clavicle is the last bone to ossify.

16

What does the clavicle protect? What does this mean?

The apex of the lung, the brachial plexus and the major underlying vessels SO all at risk if clavicle is damaged in a fracture for example fragments of bone can damage lungs causing pneumothorax

17

What ribs does the scapula over lie?

2nd-7th ribs

18

What does the spine of the scapula separate?

The supraspinous fossa and the infraspinous fossa

19

What is at the lateral end of the scapula?

The acromion which forms the subcutaneous point of the shoulder

20

What is the shape of the scapula?

triangular and flat

21

What features are seen on the anterior view of the scapula?

Glenoid cavity, acromion, coracoid process, subscapular fossa

22

What features are seen on the posterior view of the scapula?

Supaspinous fossa, coracoid process, acromion, supraspinous fossa, neck of scapula, infraspinous fossa

23

What is the largest bone in the upper limb?

Humerus

24

Where does the humerus articulate with the scapula?

Glenohumeral joint

25

What is a tuberosity and what bone has it?

Protuberance for muscle tendons to attach to
Humerus - greater tuberosity is larger and anterior, lesser tuberosity,

26

What separates the tuberosities

Bicipital groove/inter-tubicular groove which tendon form coracoid process runs through

27

What are the 3 main joints in the shoulder?

Sternoclavicular Joint
Acromioclavicular Joint
Glenohumeral Joint

28

What structures meet at the sternoclavicular joint?

Manubrium of the sternum, clavicle, 1st costal cartilage

29

What is the strongest joint and the weakest joint?

Strongest - sternoclavicular
Weakest - Glenohumeral joint

30

What ligaments are in the sternoclavicular joint?

Costoclavicular ligament
Anterior sternoclavicular ligament
Interclavicular ligament

31

What does the costoclavicular ligament attach?

The sternoclavicular joint to the 1st rib limiting its movement

32

Why does the sternoclavicular joint have limited movement?

Costoclavicular ligament joins sternoclavicular joint to 1st rib

33

What is the role of the interarticular disc?

Holds the manubrium and the clavicle together and closely packs them, made up of fibrous tissue

34

What structures make up the acromioclavicular joint?

Acromion and clavicle

35

Where is the acromioclavicular joint found?

2-3cm from the point of the shoulder

36

What is special about the acromioclavicular joint?

No muscles cross it and instead it is moved by the muscles of the scapula

37

How strong is the acromioclavicular joint?

stronger than glenohumeral joint but weaker than sternoclaviular joint

38

What movement can occur in the acromioclavicular joint? What muscles cause them?

Related to scapula movements:
depression (gravity)
elevation (trapezium)
Protraction (serratous anterior and pectoralis minor)
Retraction (trapezium)
Upward rotation (trapezium and serratous anterior)
Downward rotation (latissimus dorsi)

39

What is special about the latissimus dorsi?

It is the only muscle which moves both the upper and lower limb

40

What structures make up the glenohumeral joint?

Glenoid cavity and the humerus head

41

What is the glenoid labrum? What is its role? How does it work?

Shallow glenoid cavity which is deepened by the fibrocartilage ring. Forms a suction cup to hold the humerus head inside the cavity, thin film of synovial fluid between the humerus and the glenoid cavity creates surface tension

42

What is the weakest joint in the body?

Glenohumeral joint

43

How is there such a large freedom of movement at the glenohumeral joint?

Loose fibrous joint capsule, baggy with lots of space around the humerus head

44

What movements can occur at the glenohumeral joint and by which muscles?

Flexion - deltoid (anterior part), pectoralis major, coracobrachialis stabilises the joint
Extension - latissimus dorsi, deltoid (posterior part), teres major, triceps brachi stabilise joint
Abduction - deltoid (all of it), supraspinatus for the last 10 degree
Adduction - latissimus dorsi, pectoralis major, mainly gravity
Medial and lateral rotation - subscapularis, suprasniatus, infraspinatus, teres minor

45

Why Is the supraspinatus at risk of damage?

As goes under the acromion

46

Where are the rotator cuff muscles and what do they do?

Form musculotendinous cuff around the glenohumeral joint which blends with articular capsule
Attach to the greater and lesser tuberosity
Contract and hold large humerous head in shallow glenoid cavity

47

What happens at the scapulothoracic joint?

Head of the humerus uses articular surface for 90 degree turn and the remainder is from scapula rotation using th serratus anterior and trapezium

48

For every 15 degree shoulder abduction how much does the glenohumeral and scapulothoracic joints contribute?

Glenhomueral - 15 degrees and scapulothoracic 5 degrees

49

In a 180 degree turn how much of the turn occurs where?

glenohumeral - 120 degrees, scapulothoracic - 60 degrees

50

What movements does scratching your back form the top use?

External rotation and abduction

51

What movements does scratching your back form the side/bottom use?

Internal rotation and adduction

52

What is a bursa?

Extension of a joint cavity

53

What is the role of bursa?

Act as cushions to reduce friction

54

What is the risk of bursa?

Bursa can become inflamed and damaged which would damage the tendon underneath

55

What is an example of bursitis?

Subacromial bursa - pain and inflammation on abduction of the arm

56

Which joint is most likely dislocated?

Glenohumeral

57

What are the movements in a glenohumeral dislocation?

joint fully abducted tilting head of humerus inferiorly onto weaker part of joint
Stronger flexor and adductor muscles pull humeral head anteriorly
Gravity pulls humerus inferiorly so rounded profile of the shoulder is lost

58

What happens to the glenoid labrum in a glenohumeral dislocation?

Stripped from anterior aspect of glenoid cavity making the joint weaker

59

How might an axillary nerve injury occur? What does this result in?

From glenohumeral dislocation as axillary nerve has close relationship with inferior part of glenohumeral joint
Innervates the deltoid so abduction is impaired
Loss of sensation over regimental badge