Shoulder girdle

Joints

Sternoclavicular
Acromioclavicular
Scapulothoracal functional unit

Scapular movements

Elevation-depression
Protraction-retraction
Rotationn

Dorsal cavity

Postero-lateral border → Subscapularis (internal rotation in glenohumeral joint)
Antero-medial → Serratus anterior

Ventral cavity

Postero-lateral border → Serratus anterior
Antero-medial → intercostal muscles

Elevation

Both scapula slide superiorly on thoracic part. There is tilting on ribcage on the superior part.

Ant. tilting and posterior part has inferior tilting.

At the end of ROM, the inf angle has external rotation

Depression

Scapula slides inferiorly on ribcage

Superior part → post tilting
Inferior part → ant tilting

At the end of ROM, we will have internal rotation

Protraction

Close shoulders anteriorly, scapula slides laterally on the ribs posteriorly.

At the end of ROM, there is external rotation

Lateral side of scapula will be tilted anteriorly, while medial side is tilted posteriorly, following the convexity of the ribs.

At the end of elevation, we have protraction

Angle between scapula and frontal plane increases, but between clavicle and frontal plane is smaller

Retraction

Closes scapula together posteriorly medially.

At the end of ROM, we have internal rotation at inferior angle. Margo medialis have anterior tilting

Opposite to protraction, the change in angles is in relation with respiration

Convex-concave rule

If convex moves on concave, direction of osteokinematic motion and arthrokinematic sliding are opposite

If concave moves on convex, direction are the same

Elevation analysis

Osteokinematic motion → Acromion end of clavicle moves superiorly.

Arthrokinematic motion → In the sternal end of clavicle, there is inferior sliding and superior rolling

Depression analysis

Osteokinematic motion → Acromion end of clavicle moves inferiorly.

Arthrokinematic motion → In the sternal end of clavicle, there is superior sliding and inferior rolling

Protraction

Concave moves on convex, acromial and sternal end moves anteriorly

Retraction

Concave moves on convex, acromial and sternal end moves psteriorly