Pectoral and Pelvic Girdles

Question 1

which bones form the pectoral girdle?

Answer 1

scapula and clavicle

Question 2

what are features of the pectoral girdle?

Answer 2

• attaches the UL to axial skeleton
• augments free movement of limb
• is mobile and moves simultaneously with UL

Question 3

which bones form the pelvic girdle?

Answer 3

• hip bone (ilium, ischium and pubis)
• sacrum
• coccyx

Question 4

what are features of the pelvic girdle?

Answer 4

• attaches LL to axial skeleton

- provides an almost rigid, complete ring for weight bearing and child birth

Question 5

what do both the pectoral and pelvic girdles provide?

Answer 5

• “gateways” for neurovascular structures to pass to and from limbs
• muscle attachment for limb movement

Question 6

what is the function of the clavicle?

Answer 6

• acts as a strut, holding the upper limb away from the trunk
• transmits forces from the upper limb to the trunk

Question 7

describe the physical features of the clavicle

Answer 7

lateral end: flat and articulates with acromion

medial end: quadrangular, articulates with manubrium of sternum

medial 1/3 is rounded and convex anteriorly

Question 8

where does the coraco-clavicular ligament attach?

Answer 8

• conoid tubercle

- trapezoid line

Question 9

what are features of the scapula?

Answer 9

• triangular bone on the posterolateral aspect of thorax
• suspended in muscles, held in position by clavicle
• overlying the 2nd - 7th ribs

Question 10

what are the 3 margins of the scapula?

Answer 10

• superior
• medial
• lateral

Question 11

what is the superior angle of the scapula level with?

Answer 11

2nd rib

Question 12

what is the inferior angle of the scapula level with?

Answer 12

7th rib

Question 13

how many fossa feature on the scapula?

Answer 13

3: supraspinous, infraspinous and glenoid

Question 14

what is the purpose of the glenoid fossa?

Answer 14

to articulate with the humerus

Question 15

what is the significance of the sternoclavicular joint?

Answer 15

it is the only site of attachment of the pectoral girdle to the body

Question 16

what are features of the sternoclavicular joint?

Answer 16

• synovial joint with joint capsule and intra-articular disc that is attached to clavicle, manubrium and capsule

Question 17

how is the capsule of the sternoclavicular joint strenghtened?

Answer 17

• by ligaments anteriorly and posteriorly

- plus interclavicular and costoclavicular ligaments

Question 18

where does the subacromial bursa lie?

Answer 18

in the narrow “space” between GH joint capsule and acromion, acromioclavicular joint and coraco-acromial ligament

Question 19

what lies next to the subacromial bursa?

Answer 19

tendon of supraspinatus muscle

Question 20

how might injury occur to supraspinatus?

Answer 20

due to arthritis in adjacent joints and repetitive strain injury

Question 21

what are features of a synovial joint?

Answer 21

allows a small range of gliding movement

Question 22

what makes up the major ligamentous support of the acromioclavicular joint?

Answer 22

conoid and trapezoid parts of the coraco-clavicular ligament

Question 23

where is the gateway for the pectoral girdle to the upper limbs?

Answer 23

between the clavicle, superior edge of scapula and the first rib

Question 24

what passes through the pectoral girdle “gateway” to the axilla?

Answer 24

• subclavian vessels

- trunks of brachial nerve plexus

Question 25

where do the bones of the hip articulate with each other?

Answer 25

pubic symphysis

Question 26

what is the relationship between the ASIS and pubic tubercle?

Answer 26

on the same coronal plane

Question 27

what are features of the pubic symphysis?

Answer 27

- secondary cartilaginous/fibrocartilage joint between left and right pubic bodies - supported by superior and anterior ligaments - disc between articular surfaces - limited movement, and shock absorption

Question 28

what are features of the sacro-iliac joint?

Answer 28

- for weight transfer, extremely limited movement - synovial anteriorly and supported by anterior sacro-iliac ligament - fibrous posteriorly, supported by posterior sacro-iliac and interosseous ligaments

Question 29

which ligaments prevent sacrum tilting forwards?

Answer 29

- sacrospinous | - sacrotuberous

Question 30

what are the roles of sacrospinous and sacrotuberous ligaments?

Answer 30

- prevent sacrum tilting forward | - convert sciatic notches into GREATER and LESSER sciatic foramina

Question 31

what structures pass through the greater sciatic foramen?

Answer 31

- sciatic nerve | - gluteal neurovascular bundle

Question 32

what structures pass through the lesser sciatic foramen?

Answer 32

internal pudendal neurovascular bundle

Question 33

what gateway does the femoral neurovascular bundle pass through?

Answer 33

the gap between inguinal ligament and pelvic bone

Question 34

what structures pass through the obturator canal?

Answer 34

obturator neurovascular bundle

Question 35

where is the safe area for intramuscular injections?

Answer 35

upper, outer quadrant

Question 36

where does the sciatic nerve emerge?

Answer 36

- into gluteal region - inferior to piriformis - midway between ischial tuberosity and greater trochanter

Question 37

what are the movements of the pectoral girdle?

Answer 37

1. elevation and depression 2. protraction and retraction 3. rotation of the scapula so glenoid fossa faces upwards or downwards (abduction of arm)

Question 38

what does serratus anterior form?

Answer 38

medial wall of axilla

Question 39

what nerve descends superficially to serratus anterior?

Answer 39

long thoracic nerve

Question 40

what is the origin of trapezius?

Answer 40

- superior nuchal line - external occipital protuberance - nuchal ligament - spinous processes of C7-T12 - supraspinous ligaments between C7-T12

Question 41

what is the insertion of trapezius?

Answer 41

- lateral 1/3 of clavicle - acromion - spine of scapula

Question 42

what muscles act on the pectoral girdle?

Answer 42

- trapezius - serratus anterior - pectoralis minor - subclavius - levator scapulae - rhomboid major - rhomboid minor