Shoulder Girdle
Joints
- Sternoclavicular
- Acromioclavicular
- Scapulothoracic
Motions of scapulothoracic
Frontal plane
Elevation- composite of sternoclavicular and acromioclavicular rotations
Depression- reverse action
Horizontal plane
Protraction- horizontal plane rotations at sternoclavicular and acromioclavicular joints
Retraction: similar but reverse
, Front or scapular plane
Upward rotation- summation of clavicular elevation and upward rotation, range: 60
Downward rotation- linked to depression of clavicle and downward rotation of
acromioclavicular joint
Sternoclavicular
Where the clavicle meets manubrium and first rib costal cartilage
Saddle joint- one part is concave and the other is convex
From inferior to superior - clavicle is convex and manubrium is concave
From medial to lateral- clavicle concave and manubrium convex
Elevation of clavicle
Roll superiorly and glide inferiorly
Protraction and retraction- connected to adduction and abduction of scapula
Anterior glide and rotation of lateral clavicle
Ligaments
- Anterior sternoclavicular- reinforce capsule anteriorly, limits anterior translation of
clavicle, checks anterior movement of head of clavicle
- Posterior sternoclavicular-reinforce capsule posteriorly, limits posterior translation of
clavicle, checks posterior movement of head of clavicle
- Interclavicular ligament- strengthen capsule superiorly, resist excessive depression-
taut only in depression
- Costoclavicular ligament - limit elevation of pectoral girdle, check clavicular elevation
and superior glide of clavicle, acts as fulcrum for elevation, depression, protraction,
retraction
Osteokinematics of sternoclavicular
Elevation: 0-30- lateral end of clavicle elevates while the medial end depressors, at medial
end accessory roll and slide- limited by tension of costoclavicular ligaments and tone of
subclavius muscle
Depression: 0-10- opposite- limited by the articular disc and tension of interclavicular ligament
Muscles- levator scapulae, trapezius upper, pectoralis minor, trapezius lower, rhomboids,
serratus anterior inferior
Protraction- 0-15- lateral end of clavicle moves forwards while medial end moves posteriorly-
limited by costoclavicular and anterior sternoclavicular ligament
Retraction- 0-15- opposite- posterior sternoclavicular and costoclavicular ligament
Joints
- Sternoclavicular
- Acromioclavicular
- Scapulothoracic
Motions of scapulothoracic
Frontal plane
Elevation- composite of sternoclavicular and acromioclavicular rotations
Depression- reverse action
Horizontal plane
Protraction- horizontal plane rotations at sternoclavicular and acromioclavicular joints
Retraction: similar but reverse
, Front or scapular plane
Upward rotation- summation of clavicular elevation and upward rotation, range: 60
Downward rotation- linked to depression of clavicle and downward rotation of
acromioclavicular joint
Sternoclavicular
Where the clavicle meets manubrium and first rib costal cartilage
Saddle joint- one part is concave and the other is convex
From inferior to superior - clavicle is convex and manubrium is concave
From medial to lateral- clavicle concave and manubrium convex
Elevation of clavicle
Roll superiorly and glide inferiorly
Protraction and retraction- connected to adduction and abduction of scapula
Anterior glide and rotation of lateral clavicle
Ligaments
- Anterior sternoclavicular- reinforce capsule anteriorly, limits anterior translation of
clavicle, checks anterior movement of head of clavicle
- Posterior sternoclavicular-reinforce capsule posteriorly, limits posterior translation of
clavicle, checks posterior movement of head of clavicle
- Interclavicular ligament- strengthen capsule superiorly, resist excessive depression-
taut only in depression
- Costoclavicular ligament - limit elevation of pectoral girdle, check clavicular elevation
and superior glide of clavicle, acts as fulcrum for elevation, depression, protraction,
retraction
Osteokinematics of sternoclavicular
Elevation: 0-30- lateral end of clavicle elevates while the medial end depressors, at medial
end accessory roll and slide- limited by tension of costoclavicular ligaments and tone of
subclavius muscle
Depression: 0-10- opposite- limited by the articular disc and tension of interclavicular ligament
Muscles- levator scapulae, trapezius upper, pectoralis minor, trapezius lower, rhomboids,
serratus anterior inferior
Protraction- 0-15- lateral end of clavicle moves forwards while medial end moves posteriorly-
limited by costoclavicular and anterior sternoclavicular ligament
Retraction- 0-15- opposite- posterior sternoclavicular and costoclavicular ligament
