shoulder girdle Flashcards
What does the shoulder girdle consist of
Scapula
Clavicle
Describe the clavicle
Medial end:
- rounded triangular cross section
- convex forwards
- Articulated with sternum
Lateral end:
- broad and flattened
- concave forwards
- articulates with acromion of scapula
Attachments for each surface on clavicle
Deltoid tubercle; attachment of anterior fibres of deltoids
Trapezoid line and conoid tubercle- attachment of the coraclavocular ligament
Subclavian groove; for subclavian vessels
Costal tuberosity; attachment of costoclavicular ligament
Describe scapula and borders
3 borders
2 angles
2 surfaces
3 bony processes
Bony features of scapula
Spine acromion process
Glenoid cavity
Different fossas
Suprascapular notch
Sternum
Manubrium
Sternum
Xiphoid
Sternal notch= juglular notch
Sternal angle=angle of Louis
Describe acromioclavicular joint
Synovial plane,
- small oval facets on lateral clavicle and medial acromian
- covered by fibrocartilage
- inra-articular disc
capsules
- attached to articular margins
- strengthened by fibres above and below acromiclavicular ligament
ligaments: coraclavicular consists of trapezoid ligament and conoid ligament
movement small glides
describe sternoclavicular
synovial saddle
clavicle convex, covered by fibrocartilage
manubrium sterni concave covered by hyaline cartilage + costal cartilage of first rib
contains intra articular disc
what are the sternoclavicular capsule
surrounds joint strengthened by 3 ligaments
anterior sternoclavicular
posterior sternoclavicular
inter-clavicular ligament
movement is small glides
grades of ligament tear
grade 1- ligament stretch = clavicle displaced posterior over acromion
grade 2- partial rupture of A.C ligaments= clavicle displaced under skin
grade 3- complete rupture of A.C. and C.C. ligaments= clavicle underneath coracoid very rare!
movements at shoulder girdle and muscles
elevation-
upper fibres of trapezius
levator scapulae
10cms up
depression gravity serrates anterior pectoralis minor 2cms
protraction
serrates anterior
pectoralis minor
5cms
retraction rhomboid major rhomboid minor midele trapezius 2cms
lateral rotation
upper and lower fibres of trapezius
serrates anterior
medial rotation
the rhomboids
pectoralis minor
levator scapulae
action of trapezius of each fibre
upper fibres-
elevation of shoulder girdle
middle fibres-
retraction of shoulder girdle
lower fibres
depression of scapula against resistance
upper lower fibres together with serrates anterior
-lateral rotation of scapula to increase movement of upper limb
functional activities of trapezius
steadies scapula and clavicle=
- against gravity or when weights are carried in the hand
e. g. vacuuming
provides fixation (both sides) - controls head position, leaning forwards in writing or reading
produces lateral rotation of scapula (upper and lower)
e.g. brushing/combing hair
produces retraction (middle) -putting on coat
produces depression of scapula against resistance (lower)
-putting on coat
produces depressions
functional activities of trapezius
steadies scapula and clavicle=
- against gravity or when weights are carried in the hand
e. g. vacuuming
provides fixation (both sides) - controls head position, leaning forwards in writing or reading
produces lateral rotation of scapula (upper and lower)
e.g. brushing/combing hair
produces retraction (middle) -putting on coat
produces depression of scapula against resistance (lower)
-putting on coat
produces depressions of scapula against resistance (lower)
shoulder girdle increases range of activity of upper limb how?
changing position of glenoid fossa, relative to chest wall
clavicle holds shoulder away from chest wall
