Lecutre 7a: Shoulder Complex Fucntional Antomy And Biomechnasi

Question 1

What are the 4 joints of teh shoulder complex

Answer 1

• Gleno-humeral joint
• Acromio-clavicular joint
• Sterno-clavicular joint
• Scapulo-thoracic joint

Question 2

What is the primary and secondary function of the shoulder

Answer 2

Primaryly position hand in space to permit upper limb to interact w environment

Secondary to suspect upper lift and serve as a fulcrum for arm elevation

Question 3

What is the closed packed position and open packed position

Answer 3

• CPP: 90° of ABD (or full) and full ER
• OPP: 55° of ABD and 30° horz
adduction

Question 4

What is the capsular pattern of the shoulder

Answer 4

ER > ABD > IR

Get IR back last

Question 5

What are passive structures of the GH joint

Answer 5

• Labrum
• Capsule
• Ligaments

Question 6

What are the active structures of the GH joint

Answer 6

• Rotator cuff mm.
• Scapular mm

Question 7

What are the 5 key elements of GH stabilization

Answer 7

• ossesous structures : concavity of glenoid fossa
  -glenoid labrum
• capsule ligamentous structures
• muscular structures
• mechanoreceptors

Question 8

What are the 3 things of the concavity of the glenoid fossa

Answer 8

• (-) intra-articular pressure
• Limited joint volume
• Adhesion / cohesion

Question 9

Is the labrum avasualr or vascular

Answer 9

Avascular does not heal itself

Question 10

The average depth of the glenoid fossa is doubled by what

Answer 10

Labrum

Question 11

What is the stabilizing effect to limit translation in the labrum

Answer 11

Chock block

Question 12

What does the glenoid labrum increase

Answer 12

Total surface area for articulation enhancing concavity compression effects

Question 13

The labrum aids in attachment of what

Answer 13

GH ligaments to glenoid

Question 14

How is the GH capsule

Answer 14

Large , loose and redundant

Question 15

How much static stability does the GH capsule afford

Answer 15

Minimal

Question 16

What is the normal fluid volume in **GH capsule ? **

Adhesive capsulitis

Capsular laxity

Answer 16

• Normal volume 10-15 ml
• Adhesive capsulitis 5-10 ml
• Capsular laxity up to 30 ml

Question 17

What 2 ligaments are in the anterior complex of the GH

Answer 17

Superior GH ligament and middle GH ligament

Question 18

When is the superior GH ligament taut

Answer 18

W arm by side (0° of abduction)

Question 19

What is the superior GH ligaments covered by and what does it aid in

Answer 19

• Covered by coraco-humeral ligament
• Aids RC muscles to support suspended
humeral head

Question 20

**

When the superior GH lig is incompetent how will the humeral head subluxa

Answer 20

Inferiorly

Question 21

If the shoulder sublux anterior what ligament will be damaged

Answer 21

Middle GH lig

Question 22

What is the middle GH lig a secondary restraint to

Answer 22

Anterior translation

Question 23

What. Lig is in the inferior complex of the GH capsule

Answer 23

Inferior GH ligament

Question 24

What complex is the main static stabilizer of an abducted shoulder

Answer 24

Inferior

Question 25

When does the interior GH ligament become taut

Answer 25

Abduction

Question 26

What happens to the **inferior** GH ligaments when the shoulder if **rotated**

Answer 26

Fans out to support humeral head

Question 27

In the **inferior** complex the hammock like anatomy of the **axillary pouch** allows what

Answer 27

Reciprocal tightening of anterior and posterior structures w arm motin

Question 28

What complex is there w **no distinct capsular ligaments**

Answer 28

Posterior complex

Question 29

The majority of posterior stability comes from what

Answer 29

Dynamic stabilizers

Question 30

What does the **posterior** **band** of the **inferior** GH lig provide

Answer 30

Stability to humeral head when arm is abducted 90° and IR

Question 31

What are the 3 well recognized functions of the RC mm

Answer 31

• Control osteokinematic and arthrokinematic motion • Rotate humeral head • Stabilize humeral head in glenoid (MAIN PURPOSE)

Question 32

The RC mm has a force couple with w other mm

Answer 32

Deltoid

Question 33

What is a force couple

Answer 33

2 or more mm or groups or mm are on opposite dies of the joint and work in concrete to add joint stability or movement of a joint

Question 34

What are 3 examples for force couple in shoulder

Answer 34

• Rotator cuff – deltoid • Upper/lower trapezius – serratus anterior • Anterior – posterior rotator cuff``

Question 35

**Dynamic** stability of the **GH** joint is achieved thru what

Answer 35

Contraction of RC mm and biceps

Question 36

What decreased capsular and ligamentous strain in the shoulder

Answer 36

Mm contraction of RC

Question 37

For **dynamic** stability u want to reinforce ___ structures thru direct attached of ___ tendons

Answer 37

Passive RC

Question 38

How do u get **NM control** for **dynamic** stability

Answer 38

Via proprioception

Question 39

How big is the **sub acromion** a space w the **arm at side**

Answer 39

10-11mm

Question 40

What happens to the **SA** space as **arm elevated**

Answer 40

Narrows Most narrow between 60-120°

Question 41

What **tendon** is most invovled in **over use syndromes**

Answer 41

Supraspinatus

Question 42

Why does the position of teh GH joint matters

Answer 42

Bc of the less and greater tubercle

Question 43

What can increase superior migration of the t humeral head

Answer 43

Muscle imbalance and capsular stiffness which then can result in damage to labrum and/or soft tissue

Question 44

Does IR or ER causes more stress on shoulder

Answer 44

IR

Question 45

Can u actively control the AC joint ?

Answer 45

No bc no mm attach here

Question 46

What kind of joint is the **AC joint**

Answer 46

True synovial , plane joint

Question 47

What is the CPP of the AC joint

Answer 47

90° abduction

Question 48

What are the **passive** structures of the **AC joint**

Answer 48

Capsule and ligaments

Question 49

T/f: the AC joint is controlled by active structures

Answer 49

NNOOOOOO F

Question 50

What is the main articulation that suspects UE from trunk

Answer 50

AC joint

Question 51

What lig is the **primary** support of the **AC joint**

Answer 51

Coraco clavicular ligament

Question 52

What are teh 2 parts of the coraco clavicaulr lig

Answer 52

Conoid and trapezoid

Question 53

What is the CPP of the **SC joint**

Answer 53

Max elevation and protraction

Question 54

What is the capsualr pattern for the SC joint

Answer 54

Extreme end ROM (especially elevation and horizontal ADD)

Question 55

What are the **passive** structures of the **SC joint**

Answer 55

Capsule , ligament and articular disc

Question 56

T/F the SC joint is controlled by active structures

Answer 56

NOOOOO NOOO NOOO

Question 57

What is the only joint that connects that shoulder girdle to the axial Skelton

Answer 57

SC joint

Question 58

Which dx is **more** common at the **SC joint**

Answer 58

Anterior dislocation

Question 59

is the SC weak or strong

Answer 59

Weak

Question 60

What is the SC secured by

Answer 60

Extremely strong ligaments

Question 61

What kind of joint is the **scapula thoracic joint**

Answer 61

False joint

Question 62

What is the OPP of the scapulo thoracic joint

Answer 62

W arm at neutral - scapular positioned 30-45° IR , slight upward rotation and 5-20° anterior tipping

Question 63

Is teh scapula thoracic joint controlled by active or passive structures

Answer 63

Active

Question 64

What does teh active structures of the ST joint link ? It also acts to do what ?

Answer 64

Links proximal trunk to UE Acts to transfer energy through kinetic chain

Question 65

When the humerus is in **70° of abduction** how much rotation is there at the scap

Answer 65

20

Question 66

When the **humerus** is **elevated to 110°** how much **rotation** is there at the scap

Answer 66

40°

Question 67

What kind of pateitns is **reverse scapulo humeral rhythm** usually seen in

Answer 67

Adhesive capsulitis RC tears

Question 68

The nerve supply of the shoulder joint is from what nerves

Answer 68

C5-C8 Except for AC joint - C4

Question 69

Where does the **sympathetic** nerve supply **originate** form

Answer 69

T2-T8

Question 70

The **vascular** supply to shoulder complex is **primarily** from what

Answer 70

Branches off axillary artery

Question 71

What artery supplies **both heads of the biceps**

Answer 71

Brachial artery