Shoulder complex Flashcards
Scapulothoracic joint
Made up of?
Functions?
Scapula and rib cage
Elevation/depression
Protraction/retraction
Upward/downward rotation of scapula
Sternoclavicular joint
Made up of?
Functions?
Sternum and clavicle
elevation/depression
protraction/retraction
and rotation of the clavicle
Acromioclavicular joint
Made up of?
Functions?
Acromion and clavicle
protraction/retraction of scapula
Coracoclavicular ligament
Attaches to?
Functions?
Coracoid process and clavicle
prevents overriding and narrowing of the angle b/w clavicle and scapula
restricts vertical movement of clavicle, prevents widening of the angle b/w clavicle and scapula
Glenohumeral joint
Made up of?
Functions?
Glenoid fossa and humerus
flexion/extension, abduction/adduction, and medial and lateral rotation
Pec major
Attaches to?
Functions?
Attachments:
clavicular head: medial half of clavicle
sternocostal head: anterior surface of sternum, costal cartilages 1-6
Lateral lip of intertubercular sulcus
Actions:
adducts and medially rotates humerus, draws (indirectly) scapula anteriorly and inferiorly. Clavicular head alone flexes humerus; sternocostal head alone extends humerus from flexed position
Pec minor
Attaches to?
Functions?
Attachments:
ribs 3-5 near costal cartilages
coracoid process
Actions:
stabilises scapula by drawing it anteriorly and inferiorly
Subclavius
Attaches to?
Functions?
Attachments:
junction of 1st rib and 1st costal cartilage
inferior surface of middle third of clavicle
Actions:
anchors and depresses (acromial end) clavicle
Serratus anterior
Attaches to?
Functions?
Attachments:
lateral aspect of ribs 1-8
(anterior aspect) medial border of scapula
Actions:
protract scapula, rotate scapula superiorly (lower fibres), hold scapula to thorax
Levator scapulae
Attaches to?
Functions?
Attachments:
transverse processes of C1-C4
medial border of scapula, superior to the root of the spine of the scapula.
Actions:
elevate scapula, rotate scapula inferiorly
Trapezius
Attaches to?
Functions?
Attachments:
superior nuchal line, external occipital protuberance, nuchal ligament and spinous processes C7 - T12
lateral third of clavicle, acromion and spine of scapula
Actions:
descending part elevates scapula, ascending part depresses scapula, central fibres retract scapula, descending and ascending together rotate glenoid cavity superiorly
Latissimus dorsi
Attaches to?
Functions?
Attachments:
spinous processes of T7-12, thoracolumbar fascia, iliac crest, ribs 9-12
intertubercular sulcus
Actions:
extends, adducts and medially rotates humerus
Rhomboid major and minor
Attaches to?
Functions?
Attachments:
minor: C7 and T1
major: T2 - T5
medial border of scapula
Actions:
retract scapula, rotate glenoid cavity inferiorly
Deltoid
Attaches to?
Functions?
Attachments:
lateral third of clavicle, acromion and spine of scapula
deltoid tuberosity of humerus
Actions:
anterior fibres flex and medially rotate arm, posterior fibres extend and laterally rotate arm, all fibres are active in abduction
Supraspinatus
Attaches to?
Functions?
Attachments:
supraspinous fossa of scapula
greater tubercle of humerus
Actions:
initiates abduction, maintains apposition of head of humerus and glenoid cavity during motion
