Serratus Anterior
O- lateral surfaces of upper 8-9 ribs and deep fascia overlying the related intercostal spaces
I- costal surface of medial border of scapula
A- protraction and lateral rotation of the scapula
I- long thoracic nerve
Keeps medial border and inferior angle of scapula opposed to thoracic wall
What is depression?
when we push the shoulders down the clavicle moves slightly upwards
acronium moves slightly downwards
What is it produced by?
gravity
serratus anterior and pectoralis minor if you want to depress further
What is it limited by?
interclavicualar ligament and interarticular disc
What is the range of depression?
2cms from normal posture
Pectoralis Minor
O- anterior surfaces ad superior borders of ribs 3,4,5 and from deep fascia overlying the related intercostal spaces I- coracoid process of scapula I- medial pectoral nerve C5,C6,C7,C8,T1 A- pulls tip of shoulder down protracts and medial rotates the scapula accessory muscle of inspiration