Kinesiology Exam 3

Shoulder Girdle

Sternoclavicular joint

-diarthrodial classification (arthrodial-gliding)

-movements of clavicle: anterior, posterior, superior, inferior, some rotation

-supported by: anterior and posterior SC ligaments

acromioclavicular joint

-diarthrodial classification (arthodial)

-supported by: coracoclavicular ligaments and superior and inferior acromioclavicular ligaments 

-often injured 

scapulothoracic joint

not a true synovial joint, scapula moves on the rib cage 

-movement depends on SC and AC joints

-supported dynamically by: muscles not ligaments 

protraction of scapula

abduction, moves laterally away

-putting arms out in front of you

retraction of scapula

adduction, squeezes shoulder blades together

downward rotation

returning inferior angle inferomedially towards spinal column, shoulder blades going back to normal position

upward rotation

turning glenoid fossa upward and moving inferior angle superolaterally away from spinal column

depression

downward movement, returning scapula to normal postion

elevation

upward movement, shrugging the shoulders

protraction and retraction plane and axis

transverse plane, vertical axis 

-considered a rotational movement 

frontal plane, sagittal axis movements

upward and downward rotation, elevation and depression

lateral tilt

during protraction, scapula rotates on vertical axis

-posterior movement of medial border and anterior movement of lateral border

medial tilt

-during extreme retraction

-anterior movement of medial border and posterior movement of lateral border

anterior tilt

-occurs during glenohumeral hyperextension

-superior border moves anteroinferiorly and inferior angle moves posterosuperiorly 

posterior tilt

-occurs during glenohumeral hyperflexion

-superior border moves posterosuperiorly and inferior angle moves anteroinferiorly

functions of muscles

stabilize scapula so joint has stable base for moving humerus, support and enhance joint movement