Shoulder Joint Muscles Flashcards
The deltoid spans how many bones
2
The deltoid arises from
lateral spine of the scapula, passing across the acromion to the lateral third of the clavicle.
The deltoid distal attachment
deltoid tuberosity of the humerus
The deltoid distal attachment
deltoid tuberosity of the humerus
Anterior fibres of deltoid do what?
flex and medial rotate at the shoulder joint
The middle fibres of deltoid action
abduct the arm at the shoulder joint
The posterior fibres of deltoid action
extension and lateral rotation at the shoulder joint
Nerve supply to deltoid?
Axillary Nerve
In what common injury is this nerve often trapped and therefore damaged?
Shoulder Dislocation
The pectoralis major muscle origin
from the medial third of the clavicle, sternum and costal cartilage of the first 6 ribs and rectus sheath!
Distal attachment of pectoralis major muscle
the intertubercular lip/sulcus of the bicipital groove of the humerus
Pectoralis Major Muscle action
on the shoulder joint is to adduct the shoulder and medially rotate the humerus at the glenohumeral joint.
Pectoralis Minor action
stabilise scapula
Serrates Anterior inserts into
Scapula
Superior fibres of trapezius actions
elevates and rotates the scapula
Middle fibres of trapezius actions
retract scapula
Inferior fibres of trapezius actions
pull scapula inferiorly
Trapezius innervation
Accessory Nerve
Which foramen of skull does accessory nerve pass through
Jugular
Flexion of shoulder muscles
Pec Major, Ant Deltoid, Coracobrachialis
Extension of Shoulder muscles
Pos Deltoid, Lat Dorsi and Teres Major
Adduction of Shoulder muscles
Pec Major, Lat Dorsi, Teres Major
Abduction of Shoulder muscles 0-90 degrees
Supraspinatus and Deltoid
Abduction of shoulder joint 90 to 180 degrees muscles
Trapezius and Serratus Ant
Medial or Internal Rotation of Shoulder Muscles
Subscapularis, Lat Dorsi, Pec Major, Teres Major
Lat or External Rotation of shoulder muscles
Infraspinatus, Teres Minor
