Shoulder Complex Flashcards
Motions at the scapulothoracic joint
-elevation
-depression
-retraction
-protraction
-upward rotation
-downward rotation
motions at the GH joint
-abduction
-adduction
-flexion
-extension
-external rotation
-internal rotation
sternoclavicular joint type
synovial
sternoclavicular joint shape
saddle
clavicle is convex in what direction and concave in what direction
convex superior/inferior
concave anterior/posterior
CPP of SC joint
full elevation
LPP of SC joint
arm at the side
SC Elevation: plane of motion and axis
Rotation in frontal plane around a sagittal axis
SC Elevation roll and glide of clavicle and sternum
convex end of clavicle rolls superiorly and glides inferiorly on the sternum
maximal elevation of SC joint
45 degrees
Protraction of SC joint: plane of motion and axis
transverse plane motion with vertical axis
Protraction of SC joint: roll and glide
concave clavicle rolls and glides anterior on the sternum
Protraction of SC joint: amount of motion
15-30 degrees
Retraction of SC joint: plane of motion and axis
concave surface of clavicle rolls and glides posterior on the sternum
Retraction of SC joint: amount of motion
15-30 degrees
Rotation of SC joint: plane and axis
longitudinal plane sagittal axis
Rotation of SC joint: direction of rotation
superior clavicle rotates posteriorly due to tension on the coracoclavicular ligament
Rotation of SC joint: amount of motion
rotates 20-35 degrees
Stabilizing structures of the SC joint
-capsule
-sternoclavicular ligaments
-interclavicular ligaments
-costoclavicular ligaments
-articular discs
-muscles
function of Ant. and Post. sternoclavicular ligaments
-reinforce capsule
-limit ant/post movement of clavicle
interclavicular ligament: location and function
-cross superior aspect of SC joint
-attach to medial ends of clavicle
-provide superior joint stability
costoclavicular ligaments: location and function
- attach first rib to inferior surface of clavicle
-check elevation of the clavicle on the first rib
articular disc: location and function
-fibrocartilage that divides joint into med and lat cavities
- shock absorption
-provides stability
stabilizing muscles of the SC joint
sternocleidomastoid
sternothyroid
sternohyoid
AC joint type
plane synovial joint (3 degrees of freedom)
shape of joint surfaces of AC joint
sometimes concave sometimes convex (don’t need to know arthrokinematics)
CPP of AC joint
90 degrees of ABD
LPP of AC joint
arm at the side
upward rotation of AC joint: movement of acromion to clavicle
acromion moves up and outward in relation to the clavicle
upward rotation of AC joint: amount of motion
up to 30 degrees with arm elevation
downward rotation of AC joint: movement of acromion to clavicle (include axis)
acromion moves down and inward in relation to the clavicle, sagittal axis
Transverse plane movements of AC joint: axis
vertical
Transverse plane movements of AC joint: motion of the scapula
medial border of scapula moves closer or further away from the thorax (IR and ER)
Sagittal plane movements of AC joint: axis
frontal axis
Sagittal plane movements of AC joint: motion of scapula
inferior angle of scapula tips away or towards thorax (ant and post tilting)
stabilizing structures of the AC joint
-superior and inferior AC ligaments
-coracoclavicular ligament
-articular disc
-muscles
superior and inferior acromioclavicular ligaments: location and function
-attaches tot he acromion and clavicle
-reinforce the AC joint capsule
coracoclavicular ligaments: location and function
- bind clavicle to coronoid process of scapula
-control vertical joint stability
-check upward rotation
-check medial displacement of clavicle
-create longitudinal rotation of clavicle
coracoclavicular ligaments: parts
trapezoid - lateral portion
conoid - medial portion
what is a step deformity at the AC joint?
Acromioclavicular joint dislocation occurs when the clavicle separates from the scapula.
stabilizing structures of the AC joint: muscles
upper trapezius
deltoids
Location of the scapulothoracic “joint”
between 2nd and 7th ribs about 6 cm from the spinous processes
movements at the scapulothoracic “joint”
-elevation
-depression
-retraction
-protraction
-upward rotation
-downward rotation
elevation of the scapula: prime movers
-upper trapezius
-levator scapulae
-rhomboid minor
-rhomboid major
depression of the scapula: prime movers
-subclavius
-pectoralis minor
-pectoralis major (lower fibers)
-lower trapezius
-serratus anterior (lower fibers)
-latissimus dorsi (lower fibers)
retraction of the scapula: prime movers
-rhomboid minor
-rhomboid major
-middle fibers of trapezius
-latissimus dorsi (upper fibers)
protraction of the scapula: prime movers
-pectoralis minor
-pectorals major
-serratus anterior
upward rotation of the scapula: prime movers
-upper trapezius
-lower trapezius
-serratus anterior
(60 degrees of scapular rotation available at ST joint)
downward rotation of the scapula: prime movers
-levator scapulae
-rhomboids major and minor
-pectoralis minor
(pectoralis major (lower fibers) and latissimus dorsi)
Function of scapular movement
-orientates glenoid fossa for optimal contact with the head of the GH
-adds range to arm elevation
-provides stable base for GH movements
