M. Instristic Shoulder Flashcards
Which movements of the shoulder are they associated with?
Upper limb
What are the 2 groups of the shoulder muscles called?
Extrinsic
Intrinsic
Where do the intrinsic originate from?
From the scapula and or/ clavicle and attach to humerus
Where does the extrinsic shoulder originate from?
From the torso, and attach to bones of the shoulder (clavicle, scapula or humerus)
What are the intrinsic shoulder muscles also known as ?
Scapulohumeral group
Where does shoulder intrinsic muscles originate from?
Scapula and or/ clavicle and attach to the humerus
How many muscles are in the intrinsic shoulder group?
6
What are the 6 muscles that are intrinsic?
Deltoid
Teres major
4 rotator cuff muscles (supraspinatus, infraspinatus, subscapularis, and teres major)
How can the deltoid muscle be divided into?
Anterior
Middle
Posterior
Where does the deltoid muscle originate from?
From the lateral third of the clavicle, the acromion and the spine of the scapula. It attaches to the deltoid tuberosity on the lateral aspect of the humerus.
What is the action of the anterior fibers of deltoid?
Flexion and medial rotation
What is the action of the posterior fibers of deltoid?
Extension and lateral rotation
What is the action of the middle fibers of deltoid?
The major abductor of the arm
Where does the deltoid muscle innervate?
Axillary nerve
Where does the teres major form?
The inferior border of the quandrangular space
